Giving an old Smartphone/Tablet a 2nd life is awesome. However, I'd suggest less destructive approaches: 1) Try using a Supercapacitor instead of a battery. That should usually work - I've already tried it on an old Samsung tablet. You may even get it in a proper form factor 2) More complex, but also doable: Modify the Android Kernel drivers. I've had the same issues with a Samsung Tablet where I modified the charging logic to only charge up to 3.8V. This caused the battery gauge to get confused and sometimes report low battery levels and the Tablet shut down. I've modified the battery gauge driver to report a percentage relative to the battery voltage instead - that worked fine. It might even be possible to modify it in such a way that it boots without battery. Huge problem here is, that this is specific for every device :/
I had a Nexus 7 installed in my car for a long time, and when battery died (most likely due to temp. variation in summer / winter) I removed it. I removed the BMS just like on video, put capacitor instead of the battery, and connected two wires "before" the BMS, to the same wires going to the tablet. Then just connected the thing directly to 5V. It worked just fine, and with wires connected "before" the BMS, tablet was showing 100% SOC all the time for some reason. There were couple things connected to tablet's USB port, like backup camera (easy cap) and audio DAC, and they were powered through tablet OTG, without external powered hub etc. Although it's probably not recommended to power the thing with 5V if battery max voltage is around 4.35V of whatever. But it survived like that for probably a year until I decided to do some changes to my setup and, in the end, switched to raspberry pi.
Your capabilities far better than you think. Lots of creators learn about IC internels and electronics and applied physics by watching your homebrews. You are GreatScott. Thanks for your contributions.
The complicated structure and circuits of modern devices I think scares many of us electronics hobbyists, myself included, from venturing into the topic of modifying or even examining them. The fact that you have done that truly shows smarts and is super nice. Great video as always.
Funny, I was looking into doing this EXACT thing with an old Nexus tablet so I could use it as a Home Assistant terminal. Good to know someone's done 99% of the work!
I wanted to install docker on a phone for this, but it seems to require kernel patches at which point I gave up. I am really confused why it isn't easier or more common to just flash a phone with a regular Linux distro GSI image. Phones are now more powerful than the home servers I'm considering, and they consume less power.
Didn't even think of that! Thanks! I have an original Galaxy Tab (yep.. the first one!) that's still running fine except for the battery life. Perfect use for it, since I just started my Home Assistant journey.
I have been trying for weeks with a Psion Netpad. It's similar issues from 2001. I think I got it when I hit the right numbers. The video gives me an idea or two more to explore.
@Rex Sceleratorum yeah but phones aren't ment to sustain running at full power for extended periods of time because they thermal throttle because they don't have cooling fans.
@@xxzenonionnex7658 There are two factors here as I hinted at. One is performance per watt per cost. Phones tend to lead here because they are made on the most efficient, advanced nodes and are still cheap because of mass production. Second is raw performance. Phones certainly cannot beat the latest 200W TDP i9 chips. But for an always-on home server raw performance is not the highest priority compared to energy efficiency. I don't plan on running my home server at full power for extended periods. In fact my current server (Atom processor) sits at near 0% most of the time. As it should. If an SoC has a temperature problem, it can simply be throttled in the kernel and still give you more than enough performance.
@@greatscottlab whyyy it's such a good phone I use a s10 but the s10e is just as good imo and still relevant to this day I'd rather use a phone that's worth £20-40
Yeah That's great..i did this same project about an year ago with samsung note 5 to integrate the device with a OBD2 powered vehicle bus can ..i did use this device in my car as dashcam , gps tracker,rear camera monitor and all obd2 related value as well sensor values... I watched all yours videos since the first semester of my engineering back to 2016..you are always an inspiration for me..👍👍👍
I had the same experience with an old tablet that I wanted to use as a wall clock; however, I found a different solution that I think you might appreciate. I saw that my tablet did the same strange countdown to 5% battery with a power supply acting as the battery. I tried a regulated switching supply and a regulated benchtop linear supply... same strange countdown. Then I determined that if I could fool the tablet into thinking there was a perfect battery installed during POST and then remove said battery when the operating system started, that the tablet no longer believed that it needed to charge anything. The result is the tablet reports that it is, "Plugged in and no time is spent on battery." The solution was to short the red and black leads that would connect to the battery during POST and then open those leads when the operating system starts, and it is happy ever after. To short the leads I just installed a "push to make" microswitch in the body of the tablet. Now whenever I need to start the tablet (say from a power outage) I just have to hold that switch while the tablet goes through POST and release it when I see the android system starting. This method has the advantage of no additional circuitry required and there is no charge/discharge cycle happening.
@@theoneohmresistor My understanding is that the BIOS of the tablet sees a "no internal resistance a battery" because I have shorted the wires. It doesn't short the power supply because there is no signal to the processor to try to charge the battery. To put it another way. As a battery loses charge its internal resistance goes up. This increase is the signal to charge. Of course, it is just a theory, I could be wrong. Actually, this response got me thinking about it some more so I decided to discuss it with ChatGPT4. After some discussion ChatGPT said the following, "You are correct that the tablet must have some mechanism to initiate a charge cycle, but this mechanism may not be as sophisticated as it would be in more expensive devices. The tablet's firmware might be designed to handle situations where the battery is connected and providing a voltage within a certain range. When the battery is disconnected, the firmware could be interpreting the lack of voltage or other expected battery information in an unexpected way. It's possible that when you shorted the battery terminals during POST, the tablet registered a connection and assumed a battery was present. After you removed the short and the tablet proceeded past POST, the firmware might have encountered an unusual or undefined condition where it didn't receive the expected battery information. In response, the firmware might default to assuming a fully charged battery and not initiate any charging cycles. The fact that the tablet reports a 100% charged battery and indicates being plugged in, supports this theory. The firmware might not be able to distinguish between the absence of a battery and a fully charged battery, leading to the unusual behavior you observed. Ultimately, the observed behavior is likely due to the combination of the tablet's firmware design, hardware design, and the unique conditions created by shorting the battery terminals during POST and then disconnecting them. This workaround may not be universally applicable to all tablets or devices, and the actual reason for the behavior might require a deeper investigation into the specific tablet's design and operation." So, the long and the short of it is... it is worth a try. It may work for your situation or not, but "no harm, no foul".
I’m a little scared to try that on older devices. I have once accidentally shorted the battery terminals and it would simply spark and short the power supply directly. Nothing broke but the phone didn’t want to charge, it gave a warning pop-up when plugging the charger in. It may work on some protection circuits but I think it’s a risky approach. I would assume most devices require the middle pin to have a signal for safety reasons. Chatgpt unfortunately isn’t the most trustworthy source, it is always super convinced that it’s telling the truth and tries to convince you that it’s correct, unless you show that it’s wrong, then it may admit that what it said was false. It can be annoying sometimes and I don’t fully trust chatgpt anymore after catching it lying multiple times, and when I would say no that’s incorrect it’d always go “oh yes you’re right, here’s the correct response”.
The old PDAs had fancy desk stands that worked on mains power (and charged batteries). Many stands were heavy, stable and perfectly angled for viewing. Look at the Palm & Dell Axim for examples that could be modded or used as inspiration.
With this schematic I think you could use the existing usb plug on the phone to power the whole thing. Just tap off the 5v from it (from the connector or the board) and running it to the diode circuit should work right? Would save the hole and extra wiring. It's an awesome idea which I wil definitely do to the phones I keep around to test websites and apps on.
Yep you could - I did this with an old Nintendo GBA SP. Wired a diode from the charging port to the battery terminals to drop 0.6V and I also removed a surface mount component to stop the charging circuitry from becoming active. Turned it into a USB powered (with the right cable) GBA SP. No need to make holes in the casing.
That won't work, for 2 reasons: * The USB jack doesn't necessarily carry 5V. Modern phones use USB PD and will negotiate a higher voltage from the power supply. Furthermore, there's a brief moment (several hundred ms) before the power supply switches to the new voltage during which the power cuts out completely, with the phone being designed to run off battery for that period. * You could make it a noncompliant device and just assume it will be plugged into a legacy USB-A power supply to avoid that problem since it will always output 5V. However, USB doesn't supply enough current to power the phone. Legacy USB supplies at most 1.5 to 2 amps, which gives
@@fat_pigeonhen you can simply use a charger that doesn’t have data wires so it can’t negotiate. If you want to mod the phone to work battery less you can also just keep in mind that not all power supplies will work properly.
I was thinking the same, you can either wire it up from the charging sub board at the bottom, and I noticed on some phones it directly deliver power to the battery connector even when not battery is present, and only starts regulating the voltage when it notices there is power draw from the battery. Maybe you can wire the power from the battery terminals to the pads on the battery circuit where the battery cell should be connected. That would let you replace the battery with a small modified circuit so you can close the phone and unplug the cable to put it away but als let’s you use the phone, but the same way you can use a laptop without battery as a portable desktop computer. And best of all you would be able to still hold the phone in your hand and you don’t have to break anything. The battery itself should be stored in a dry environment and not too hot nor too cold.
@@teamredstudio7012 sounds cooler, so all you need is solder the diode between the battery positive pad and the output from the battery terminal (I've measured on my tabled and there is constant output there). This is way cleaner
You can probably fix the old phone by reflowing the power management chips with your hot air gun. It's a very common failure mode for modern devices that the tin BGA solder joints fail from thermal cycling. Fun fact military and aerospace only use leaded solder to significantly improve reliability because lead free fails far more easily.
@@MrGeri95 Toxic for whom? The amount of solder used in a smartphone is utterly tiny and if properly disposed of none of it goes into the environment. Besides there's much more toxic stuff in the battery if a phone is disposed of incorrectly. I'd gladly take a lead soldered phone that lasts for ages than a lead free that needs throwing away after two years.
This would have been the perfect test bed for a DIY super capacitor battery replacement. They are fairly simple to make, and could be made to fit exactly into the battery well.
Super capacitors are too unstable and too big...they will work only a few minutes. This is why no one use it unless you want burst power or something to back up an existing battery
@@Tailslol who says super capacitors are too unstable or too big? I think you need a bit more study time. I have made one myself that was around 8F @2.7v and smaller than a normal cell phone battery. Sure it wont contain the same energy density as a LiPo battery, but it will fully charge in a matter of a couple of minutes and works amazing as an energy storage from a small rectified generator source. Im sure that in the space in a smart phone, a super capacitor of around 25-30F could be made. This would run the phone for an hour or so and only need 5-10 minutes to fully charge.
@@TerryGilsenan clearly 5min is not enough and you should show what you did because i studied a lot those and they are far from ready in everyday use. and way too expensive.
Awesome! Still at 1:50 but now you're talking about powering devices without their batteries, I'm pumped! This maybe great with my unused phones/tablets to create dashboards for Home Assistant around my house😎. Thanks!
@@greatscottlab incredible I would like to congratulate you for the video and for sharing the knowledge I have an nvidia shield k1 tablet that is very capable, it emulates many things and very fast it even supports streaming of games fullhd movies but its battery does not hold a charge anymore I put a stepdown regulated at 3.7v 2amp it works However, the supposed battery runs out even when connected to the power supply, I will do what I taught in the video, I would like to know if I will be able to use the charging port with an otg cable because the idea is to use the tablet without battery and with joytisk usb to play, because currently if I plug a cable into the charging port it turns off
I've got a Samsung Note 4 which had all the same issues. Replaced the battery, never worked properly. The battery expanded and popped the back of the phone off. I wanted to use it for video recording, but as per Great Scott's video, when you power it up, it goes into an endless boot cycle. I might consider building this one day - but it does make the phone look kind of messed up !! 😄
Have to see which Android i 'had'; Mine did Same thing. Trouble for Years, with NO answers to why. Shutdown with Full battery - registering -0- Charge. I found out when Phone 'Opened all by itself. *8{|*
I did something similar with my Sony Ericsson Xperia Ray. I just plugged 5 volts straight to the battery terminals. It worked just fine, no battery level drop. I used it to record time-lapse over a period of a week or so. Worked out great.
The whole Swollen battery "Issue" is VERY blown out of proportions. Not only is it NOT going to happen to any phone that is being used it can happen to ANY phone left unattended for a very extended period of time. I have recently repaired an iphone x with a bettery so swollen the display was completely detached from the rest of the phone. It is recommended to charge the phone to 60% before storing the phone and charging it up to 60% every few months to maintain the battery.
This is something i would do after i get fedup of my phone dieing in mid of a game🤣 But honestly this is some nice modification because it reduces e-waste and provided many advantages like home security you mentioned above Great job🙂
This is exactly what i did for my Samsung Galaxy Tab 4 7.0 3G Released in 2014, I tried purchasing replacements but both only lasted a year so the moment it showed signs of bloating and decay for the second time I took the brains of the battery and attached a USB cable on it and placed a hole on the side then I used a 2A Original Samsung power adapter to power it. Now then, here in Asia gadgets are hella expensive, and the second hand market here lives in Facebook marketplace and in my experience with listings there they're not managing their listings, leaving already sold items unmarked and them sending you promotional nonsense or product offerings, which made this decision a good choice. One thing to note before doing this, YOU NEED A HIGH QUALITY ADAPTER, here in Asia, cheap quality power adapters supplying less than 1A of power and even if it does the thing heats up to the point the case is as hot as a mug of hot tea, so make sure you got a good one.
I believe you can run a simple server inside, and install Pi Hole in it. With rasp Pi is still hard to get, I can get tens of good specs android with cracked screen cheaply. I can control it with scrcpy for setup, and having it with no battery reduce the risk of getting exploded.
Great project! Only change I would have made is soldering the battery lines to the inside contacts of the charging port, and using an adjustable LDO to solve the 9V USB-PD problem. Unfortunately requires microsoldering, but that way you can keep some of the water resistance and don't have to cut the chassis.
@@NiceEyeballs Ideally, you should make it safe to use any adapter with any cable without blowing up the phone. Don't set traps for yourself. If you add an LDO to the battery circuit, it will be tolerant to PD voltages. That way, you don't need to mod the chassis or use particular adapters or special cables.
I don't think the charging port can carry the necessary current to keep the phone stable. This is why the phone still starts up with only the charging port connected and no battery, but reboots as the voltage drops. Even the current setup he has is probably not going to be 100% stable, as it's running off of only one USB port, which is unlikely to match the output of a battery in all situations. To get 100% stability, I've found I have to use two USB ports, one wired directly to the BMS, and one plugged into the charge port.
Usually capacity measurement is done by the "BMS" board that is attached to the battery. Otherthan than the main power lines, it has 2 more wires (probably i2s smBus). You could find the shunt resistor in the BMS and by shorting it, you should be able to keep the battery level not dropping down.
@@nnamerzyou could look for the BMS chips datasheet; from there you could find where it would be connected to, and the recommended layouts included are normally a big tip off
Phones don't have a BMS on the battery and definitely don't have any shunt resistors. They're single cell. No shunting required. The chip on a phone battery is just over-current and under-voltage protection. The extra pins are usually a basic thermistor for temperature estimates so charging can be shut down or slowed as the battery heats up.
That's great, but the problem is that Android has a power manager driver. It thinks that there is no such thing as an infinite battery and the percentages will drop and the phone will shut down. If you turn your device off and on again, everything will work again, but it will not last long, after several such reboots, the phone will not turn on at all, because the driver will think that the battery is broken.
And of course you can also power it with an external battery based charger so you could use it portably. I wonder if you could also add a small capacitor in place of the battery so you have a few seconds to switch power sources without rebooting the phone.
a better idea would be put a small voltage regulator inside and get the voltage output of the usb this way it will not need holes for cables and also make sure the voltage is ok
This is awesome, I've been using old phones as media centers and gauge clusters in project cars in a modular fashion but always worried about permanent versions using recycled droids. I just figured all lithium cells became the spicy pillow sooner or later.
Another option for always-on phones (though may not work forever) is to use a rooted kernel & charge controls via an app to let it sit at a non-100% charge. I find this causes much less swelling.
That shouldn’t be tried on a working battery, pulling the voltage lower than the minimum voltage will cause the batterie’s internal resistance to slowly rise due to crystals growing inside of it, basically killing the battery slowly. I have had a MacBook battery swell up within days of being discharged completely. That made me believe discharging batteries increases the chance of it swelling. I have also heard it’s possible to completely drain a battery to around 1 volt to keep it in long term storage, putting the battery to sleep but I don’t know what to believe since the internet gives counter intuitive information. Would it be possible to use a modified kernel and then simply disconnect the battery and only plug the in the circuit itself?
@@xvii_au yes, I store my lithium cells at around 50-60% for long term storage, in a dry space because lithium loves to react with water and release nasty gas.
This is an amazing hack, and I can give you some advice to be able to use it with any cable without making a hole in the shell : - You can look for the USB-C connector and cut all trace for D+ and D- / CC1 and 2 / SBU2 to be sure phone can't enable fast charge by any way - Next thing is solder 1 wire into VBUS pin. The result will be clean, but you need some micro soldering so it make the hack a little more difficult, bad thing is you lose the connectivity with any device thru USB :(
It reminds me of my modification I did in a Samsung tablet. It had a very weird connector that I haven't seen before, and I didn't want to buy an adapter. So I designed a 3.7V battery charger board powered via USB, created a hole for the USB port in a tablet's housing, and somehow fitted everything inside. Charging works, but the battery level keeps dropping, so every time I have to wait till the tablet shuts down due to the "low" batery, complete the charging process and power it up, so it can realize that the battery is actually full. Just for fun I'm gonna short the current shunt and see if the battery level will freeze
@@Wrublos212 I've shorted the shunt but... nope, that wasn't it. The battery level continues to drop. I think that one of the power ICs provides the data about battery usage, so I would have to hack the system or modify those tiny circuits, what I'm not capable of
@@Wrublos212 Well, actually the battery level dropped only by 1%, and the tablet went wild. More demanding apps were causing system crashes, tablet seemed to work slower
This is crazy! I was literally thinking about doing this! I have an old Samsung S9+ that I wanted to use as a dash for my truck. But I was afraid of leaving it in my truck due to the battery. Thank you for making this video!
Yea but it would have to restart every time you shut off the engine. Unless you have cig ports that stay live all the time. Then it would drain your battery
Great recycling project. 2.0 idea - could you tap the USB to power internally and power your "battery circuit", thus removing the extra wires and power supply?
That won't work, for 2 reasons: * The USB jack doesn't necessarily carry 5V. Modern phones use USB PD and will negotiate a higher voltage from the power supply. Furthermore, there's a brief moment (several hundred ms) before the power supply switches to the new voltage during which the power cuts out completely, with the phone being designed to run off battery for that period. * You could make it a noncompliant device and just assume it will be plugged into a legacy USB-A power supply to avoid that problem since it will always output 5V. However, USB doesn't supply enough current to power the phone. Legacy USB supplies at most 1.5 to 2 amps, which gives
@@fat_pigeon Thank you for this fantastic response. I read it a few times and learned a lot here. I am looking to fit a Blackberry keyboard from Tindie to a more modern phone so your post also helps point me in the right direction. Thanks again!
Interesting feature with the voltage - I did the same thing with Huawei phone and it reported the percentage based on voltage - changing the voltage even caused the battery percentage to go up :)
Excellent trick with the diode. Having converted one old phone with a swollen battery using this technique, more recently another phone started suffering from the same swollen problem. Instead of powering it permanently I simply replaced the built in battery with a slightly smaller removable battery meant for a different phone, soldering its + and - terminals to the old battery's reclaimed protection circuit board. Thus providing the old phone with a new lease of mobile life, including being able to operate it from the usual USB adapter.
for me, just replace the battery with super capacitor, and then you can use the fast charging feature although doesn't make sense, just for current spike(mostly will use the capasitor though)
I've done it with just ELECTROLYTIC capacitor (470uF or so) on Galaxy S3, so definitely possible. Although, the fact i've also added an LED with a dropoff resistor in parallel may have played a role, cause the phone is driving something constantly at low current there. Anyway, those phone ARE perfectly capable to just power themselves from USB, they just don't want to.
This is my thought also. Construct a battery eliminator from capacitors etc. to fit into the original battery space and connect to the normal battery tabs on the BMS board (extracted from actual battery). This circuit should act like a small battery, so plug the phone in to USB power and the apparently low charge battery (I.e. uncharged caps) will get charged up until sufficient to allow the phone to boot and also add a bit of a boost when required, just like an actual battery would. No additional leads into the phone which just works as it should. Ideally the total capacitance would allow leads to be swapped from one charger to another (so just a few seconds) without the phone restarting. A minute would be way more than required IMO. I am not concerned with any sort of mobility. I just want to be able to run old mobile phones/tablets for other purposes (clock, radio, HA screen, whatever) off mains/USB with no battery involved as that WILL eventually fail and expanding Li-Ion batteries in the house are to be avoided. I'm sure this is doable, but beyond my abilities to fully design. However the intended result of an intact phone that powers purely from it's original USB input is worth pursuing is it not?
I used the cheap lithium battery charger protection PCB's from china connected to a small capacitor bank to do this in the past. Works well, it's extremely cheap and easy to do
This is fantastic. I basically did the same mod but ended up with a power supply for the phine and one for the usbc to run octoprint for my 3d printer. I wasnt sure why it needed both but now i do so i bet i can make it just one now! I will also be linking this video for anyone who wants to use an android with Octo4a for their 3d printer. Its almost mandatory cause i wouldn't recommend always charging a lithium battery all the time.
Literally an hour ago I threw away old swollen battery (Sony) and want to revive the phone to get back data from it. This video is tailored for my exact situation. I love such coincidences :D
@@greatscottlab Yes, you have both reach and impact throughout the world. And I was already capable of doing such modification because of all the other videos that you've made before :) Thanks!
Very interesting! Maybe the feature to limit the SoC to 80% (around 4,2V) can be working, it's over 4,2V that the battery life is seriously reduced. Also, I remaked that old phones with a low SoH don't charge the battery over 4,2V even when displaying 100%!
Yes. Modern smartphones with their internal batteries, do a lot of 'trickery' to guesstimate a charge state, and manage how fast the battery 'ages out'. Example: Apple semi-recently was in hot water for 'gimping' old devices via OTA sw; their excuse being, old batteries can't deal with current spikes well, thus the throttling. All this project and the Apple debacle proves to me is that we never should've 'allowed' smartphones with integral batteries. From both the eWaste and "Ownership" perspectives, it was a big mistake.
This is indeed a brilliant idea! I have personally encountered a similar issue where the battery icon drains even when the device is receiving a constant power supply.
Yeah they can swell up but Mr.Whosthe boss had a whole room of smartphones and if I recall correctly only the Samsung ones were expanded and it was a couple of them, not one or two.
@@jost459 Yeh wrote it because my Ipod nano 4th generation killed itself by bloating up the battery (the screen gets smashed by the battery because they are so thinn) its also pretty known.
Thanks the idea with the diode is awesome I thought to shove there dc-dc. Only there is a problem with the battery protection it blocks the power if the voltage drops.
This video inspired me to do something similar! I had my old LG G5 that took a trip through the washing machine, I managed to save it, but the audio circuitry and battery were destroyed, I was shopping for a new webcam when I came across this video and saw my old phone just sitting there, and i decided to do this instead! The phone is now much nicer than any other webcam i could of bought, thanks Greatscott! (I did reduce the cables to just one cable however by just bridging the usb power into the charge protection chip of the old battery)
I've also done that with my Nvidia Shield Tablet in the past, after the first revision got recalled because of overheating batteries. Though as already some have mentioned I would also love to see an approach with super capacitors, to gain at least a bit of portability :)
I found a great use for my old phone. It serves as a wifi router with LTE modem. I don't use internet that much, so by using mobile internet, I pay 3x less monthly. This modification is perfect for that use.
why not solder a couple of wires to the inside of the phone's usb port that go to a step down converter that is connected to the battery protector circuit? The step down converter would probably fit where the battery used to be and all cables would run internally, only using the original USB port to feed power in
I screamed internally seeing you try to pry that back cover. Especially because I work at a service shop. Never use a screwdriver or much force when working with glass backs, also NEVER use a screwdriver when prying the battery! It's a really high chance of it either exploding or catching up in flames!
Awesome work as always but imho there was no need for external charging cable, you could have soldered charging cable lines directly to charging port internally, hope you undestand. Its just a suggestion
I did that same thing to my phone cuz the battery was busted and i was wondering why the percentage dropping while it was supplied by power supply thankfully u helped me to know 👍
Thank you so much for sharing, it will be very useful! My Zenfone 5Z battery uses the same connector and died a few months ago. There's no more support from Asus, it's like throwing away an entire gaming PC because the power supply burned out. It's disgusting to see the direction that obsolescence has taken, I don't have the money to change my phone every 3 years. Hugs from Brazil. 🥰
I was writing a comment while you mentioned it. I think it's stupid that the phones don't measure the real Voltage. I did the same with a Galaxy S3 and also came up with the same solution, It's working fine for over a year now. I use it as a timelapse camera in a grow box 😊
@@n27272 It depends on the phone - I did this on a Sony Xperia Z Ultra, and the phone did not shut off when it hit 1%, just stayed there forever. However, it would occasionally reboot (~once a week) as a single USB outlet was not enough to power it under all circumstances, so I had to also plug it into a second USB outlet via the charge port to have 100% stability. I suspect he will also have stability problems using only one USB port, but that probably depends on the power needs of the specific phone.
@@n27272 I added a USB C port for convenience, but otherwise it's a direct connection from the old battery's BMS to whatever 5v USB power I plug into it.
Great I am not alone at 03:16😅 Battery storage capacity is around 60%. sometime even with that in mind, batteries tend to swollen. It is great that some recent phone allow to "Pause" charge, and use current directly from USB port, this way is protected from constant charge, and not drained.
No, for 2 reasons: * The USB jack doesn't necessarily carry 5V. Modern phones use USB PD and will negotiate a higher voltage from the power supply. Furthermore, there's a brief moment (several hundred ms) before the power supply switches to the new voltage during which the power cuts out completely, with the phone being designed to run off battery for that period. * You could make it a noncompliant device and just assume it will be plugged into a legacy USB-A power supply to avoid that problem since it will always output 5V. However, USB doesn't supply enough current to power the phone. Legacy USB supplies at most 1.5 to 2 amps, which gives
I had a similar retrofit for moto g 6 plus a year aho. Ths phone killed two batteries in a row and was replaced by a new one. So I also cut off the bms board from the battery and used it to imitate battery with cheap buck conerter. Worked out fine and I had no need to imitate charging. So it is definitely a vendor/model thing. The device is still alive and in active use by household members.
I would love for someone to make boards for different phones and tablets that also hack into the charging port for a flawless exterior. Ebay or Tindie would be good places to sell such things.
He should try to replace the battery with capacitors (maybe ceramic). This way the internal charger will still work correctly and you can power it through the normal USB-C port.
cool, but meh... We been doing this for a long time round here but I would have done it alot differently. First off, why loosing time drilling through the phone, risk dammaging its lcd, having to endure a "trick-charge" usb c plug and the dull look. You had the phone all dissassembled, usb-c pinout are easy to find online. knowing that, you could have ran two kinar or even enameled wires INSIDE the phone itself for the trick charge... this would have not only saved space, risk and time, but also the use of the usb c cable, and the fact that if you want to use the usb wether for pc or OTG stuff, you now have the battery counter running again agaisnt you and even risk damages to certain pc, espcially the first usb 3.0 compliant hardwares... Still a brillant idea to limit e-waste, but from you Scott, we normally get project that are fully and well thought. this one feel like you might have rushed it and used less neuron than usual, maybe you were tired and they were set a neuroff? hihi < pun aside, you do amazing job entertaining us
How about connecting a 3.7v rechargeable button cell to the battery pcb? You would still need to keep the phone plugged in but it would simplify the wiring.
This sounds like a bad idea to me, cause the phone circuitry is designed to charge WAY faster than this cell would take. Wouldn't that create a mini-bomb ready to explode?
Slick video captain! Interesting so many folk have had swelling battery dilemmas. I currently have the Notes: 2 (Shelf), 4 (Shelf), 5 (Shelf), 8 (GoPro video editing), 9 (Daily DeX), 10 (Daily Phone) and fortunately I have not experienced that with any of them.
I'm detecting a problem here. Some of the chargers I've used actually output 5.2V, highest I've seen is 5.3V If you use it with one such charger, and the voltage drop is only 0.6V at that point, you could give 4.6V into the phone. Wouldn't that damage the phone? Unlikely. But still possible...
Voltages of over 4,2V in Lithium bateries are hazardous. In best case destroying batery if not bursting them in flames. Lithium bateries are most sensitive on overvoltage of all.
i have a Motorola charger that gives 5.2v at the output, even thought it says 5v 2A its fine as usb standard has +0.25v max above 5v at the usb charger Port this extra voltage its used mostly for cable voltage drop which is about 0.1v per amp, also i have a charger with 5v 3a rating that outputs 5.32v a litle bit above usb standard but also fine for devices with battery charge controller wich can handle up to 6v, it have fried 2 chinese speaker that has no ic to manages input voltage to battery ,also have fried another one of then by inserting a quick charger thinking it will be fine.
The thermistor is in the wireless charging coil circuit which I see you didn't even bothter plugging it in. Its draining because it doesn't detect the thermistor. Your diode solution is only needed for the battery for 4.3V. But now the USB-C cable is free! 😀
Do you think while using this method to keep it on you can add a USB type A connector connected to the + - and data pins that are going in the phone with the idea of using USB Flash drive or OTG for pheripherial devices ?
@@greatscottlab I have this idea for a "media player " for a car with an aux FM transmitter connected to the audio jack of the phone the phone itself powered by a 12v car phone charger and use flash drive for the music . Was wondering how the powering of the phone would work but your video came just in time to save me a lot of headache :)
Mine DID! I kept Asking WHY Phone w\ Fully charged Battery suddenly SHUT Down, registering -0- charge. NO answer. For years, Phone Temperature would get HOT at times, but not all times when it shut down. LOL NO need to Heat phone to Remove back, Battey did that for me. THAT's when i realized what was Wrong. {{sigh}} *SO Glad* there's at least *One on this Plant* that figures out How to do this. This was *Interesting* to see. *THANKS!*
This is a nice little "hack" but people should note that this solution might not work with all Samsung phones because this depends entirely on the firmware of the phone and/or what signals are connected from the battery pack to PMIC. This worked mainly because you were able to separate the BMS from the battery and the battery only utilized only power terminal and ground connections. The reboot loop you see at the start of the video when Scott tries to power only on wired connection is completely a firmware protective feature. When the device initially boots up, it initializes all the ICs and, assuming it was properly designed, will have built-in checks for this. This is just how the device's firmware handles this particular failure mode. Since its a mobile phone, obviously the primary intended use is battery power so its expected behavior. Also, in my personal experience, I've seen this type of behavior with some laptops where they prevent use of the device without a battery connected. Just my two cents as someone who develops embedded software/firmware for battery-operated consumer products.
I have some experience doing this with a few phones. Here are my experiences: For a Samsung S duos, the phone works quite happy receiving power through the battery connector (I used a diode to lower the voltage from 5V). But it would not like to receive power on the usb port at the same time. Conecting it to the pc resulted in a lot of spam of the battery not working or something like that. This phone was my very simple little server for a while. An Allview P5 Quad - bad experience. Would really not like not having the temperature pin voltage set (could be done with a voltage divider). Also, no usb power or else it would definetly not power on. I had a beefy 5V 4A power adapter, but without some beefy caps on the battery connector it would act up/randomly reboot or simply boot loop. Also, it died some time later. Allview E4 - beefy caps or have the usb connetor power as well. This phone had otg support and I managed to root it so I had plans for that otg support. Because it uses more power sometimes I intend to use a converter instead of diodes. But this one works well with or without usb. Allview V2 viper - has no otg support unfortunately. I don't remember the details, but I don't think it works properly without power on the usb port. Samsung s3 neo - doesn't work well without power on the usb. It "discharges" as the phone in the video. Also, best results with caps. I also think it doesn't like to work without the temperature pin set correctly, don't remember, also I had lineage os installed on it, so I don't know how it works using the stock ROM. Hope this helps people. Also, haven't noticed until now how many phones I tried this on. Also, surprisingly Nokia 3310 - not exactly with a supply. I found one without a functional battery and I found another smaller phone battery that would fit inside. Unfortunately the phone wouldn't be happy just with the power pins connected. I had to add a voltage divider for the temperature and another to set the battery type. It has 4 pins: +,-, temperature and battery type. Apparently the phone could have different battery types and would use a pin to determine the type. I found the values online and used that.
Could you instead replace the battery with a capacitor (or capacitor bank) and then continuously charge that using the USB cable? That way you don't have to hard wire the phone or cut holes in it for the wires.
This would probably work on a limited basis, but under continuous/heavy use the cap will get drained faster than it can be charged and the phone will die or reboot.
theoretically, but you're also have to add some circuitry to keep it for charging/discharging too much and it'd have to hold enough power to keep the battery management software from cutting it off. at that point, you might as well just put another battery in it.
@@InfernosReaper I agree that a battery might work better. Certainly a continuously connected USB cable should be able to keep up with the needs of the phone with a smaller battery than the original phone required.
The battery swelled up and popped the back off of my S8 about a year and a half ago. I took a chance and replaced it with a Chi-Com replacement from Amazon. Still works perfectly at this point in time. Cost was about $25 plus shipping. Should probably replace the phone with a new one, but I like to get as much life as I can out of my devices. Especially a device as expensive as a smart phone.
Great video! For anyone who's storing devices with LiPo batteries and doesn't want them to swell up, here's what I do that prevented my 3 Samsung phones from having this problem (one of them is a phone I bought back in 2015). I charge them to 50% before storing them, and I take them out every few months to give them a full charge/discharge cycle, before charging them back to 50% and storing them again. This seems to help all devices that have LiPo batteries in them. I haven't gotten a single spicy pillow, yet.
Couple thouths and how I'm planning to do similar thing with my phone: 1) why dont you solder to the power & ground pins of type-c connector on the motherboard? this and using simple type-c cable without data line (cheap chinese cables) OR usb charger without PD feature (old apple ones and so on) would do the same, but without hanging wires on the side of the phone 2) next level (at least what i'm planning to do) - small buck converter in the battery compartment and now you can use ANY charger regardless of their voltage! 1S bms would also do the trick, they costs maybe 50cents a piece with shipping it will be a little nicer overall. hoping you will make a follow up video with converting PoC device to something more finished
This is likely a massive overkill. I've powered an old Galaxy S3 (still got a removable battery and it DID puff up) without the battery by shorting the battery thermistor terminal to the ground (otherwise it wouldn't "charge") and hooking up a big enough electrolytic capacitor (later changing it to a bunch of small ones in parallel to fit in the battery compartment) to the battery terminals, and then hooking the USB charger as usual. I've even hooked up an LED with a dropping resistor to visually see that the phone is trying to "charge" the "battery". The phone keep happily staying in CV mode, charging my newly made "battery", thinking its at 100% charge and powering itself over USB connector and running till this very day. This said, S3 didn't power AT ALL without my little trick, yours seem to enter the bootloader, and THEN powers down when simply powered without the battery at all, so its most likely possible to circumvent by software means alone. In any case, i'd totally try to just solder a capacitor to battery protection board instead of actually powering it through there, hoping my old S3 trick would work, lol.
That was a really good and informational video on how to destructively boot smartphones without battery but i much prefer editing some kernel files to make it boot with just usb connection with or without battery. Thanks for video
I did a almost identical hack with a old android tablet. I turned it into a digital photo frame, and dedicated Spotify player. Samsung phones make handy little desktop computers with Samsung Dex. You can plug a mouse and a monitor into it.
I just came across this video while researching solutions for my old galaxy s6! I needed it for a klipper screen last night and found glass in my hand upon picking it up. Thank you for the help! Been watching for a while but subbed only a few months ago.
Maybe a more "tidy" approach like soldering from an internal 5V power source could work? If the phone draws most of its power through the usb-c port you could get away with a smaller wire inside. Or you could use a supercapacitor as a replacement for the battery to trick the phone into thinking it has one
Whatif you did all the power wiring internally? Instead of drilling a hole in the case for a modified cable, modify the actual port on the device from the inside. Pull up the data lines and put fingernail polish over them to keep from conducting with nearby pins or each other, while soldering leads off the power terminals. Now, you have a phone that looks normal on the outside, can be modified back to stock a lot more easily, and the cable is now renoveable.
This kind of project has crossed my mind in the past with phones becoming thinner and thinner and battery life becoming questionable. I figured that some kind of ultra capacitor could be used in place of the battery in combination with some kind of external case/battery type addon to power the phone for longer. This would enable the phone to continue functioning to some degree while you change the battery case and could provide a flexible solution for users that want more battery life at the expense of device size while restoring the ability for users to replace the expired/damaged battery prolonging the lifespan of the phone.
as for taking it apart, heat can be your friend..ifixit has a thing you can microwave and leave on your phone for a few min to warm it safely to help loosen adhesive
I did the same almost a decade ago with a Nexus 5 and LG F60. Nexus 5 had same issues of battery slowly going down despite being run on constant voltage. IIRC, LG F60 did not have the same issue. I used a LM step-down regulator, which includes capacitors. Function would be unstable on most low rated chargers since the peak consumption was over 2A or so.
That's a lot of effort for something preventable with battery charge limiting, built-in or available after rooting the phone. I still love the approach, of course!
I've had this swollen batter issue on a Galaxy S7, S10, and a S20 all within a year or so from purchasing them. I noticed then after I would use the phones to stream to my television for long periods of time with the otterbox case still on them. I don't know if it is a heat issue or poor quality or what. I've always assumed I mishandled them somehow and never tried to resolve it in the past. I just used them on wifi without the case after noticing this and gotten new phones for regular use. I'm somewhat of a Samsung fan so I won't be switching brands. But now I can bring those old phones out and use them safety again. Thank you.
Nice trick for re-using in stead of re-cycling an old phone. Well done. May I suggest to wire the 5V on the inside to the backside of the USB charge port connector instead of looping the charge cable on the outside?
i had tried to power up my old phone directly once long back..phone just kept rebooting..i didn't know this stupid battery percentage problem..thank you for revival of my project
I think the phone sometimes requires more than the USB can provide, therefore boot looping or turning off. And this might be related to internal electronics, not power source or cable. I believe a bigger capacitor on the battery end might solve this, but I never tested. You could have connected to the internal USB and used a buck converter for the battery. No holes or extra cables.
for a long time, i finding solution for this problem, and here you are my great teacher with the simplest neat trick thank you very much for that perfect stuff
I hope this video blows up
Haha we will see ;-)
"sad trombone"
Thats dark🌚
Groan! - for comments like this - you are banned from the internet😉
Sarcasm 😅
Giving an old Smartphone/Tablet a 2nd life is awesome. However, I'd suggest less destructive approaches:
1) Try using a Supercapacitor instead of a battery. That should usually work - I've already tried it on an old Samsung tablet. You may even get it in a proper form factor
2) More complex, but also doable: Modify the Android Kernel drivers. I've had the same issues with a Samsung Tablet where I modified the charging logic to only charge up to 3.8V. This caused the battery gauge to get confused and sometimes report low battery levels and the Tablet shut down. I've modified the battery gauge driver to report a percentage relative to the battery voltage instead - that worked fine. It might even be possible to modify it in such a way that it boots without battery.
Huge problem here is, that this is specific for every device :/
How did you do that? Can you post any resources for that?
Thanks for the feedback. Nice ideas.
i was thinking the same thing,,, then i came here and saw your comment.
I had a Nexus 7 installed in my car for a long time, and when battery died (most likely due to temp. variation in summer / winter) I removed it. I removed the BMS just like on video, put capacitor instead of the battery, and connected two wires "before" the BMS, to the same wires going to the tablet.
Then just connected the thing directly to 5V. It worked just fine, and with wires connected "before" the BMS, tablet was showing 100% SOC all the time for some reason.
There were couple things connected to tablet's USB port, like backup camera (easy cap) and audio DAC, and they were powered through tablet OTG, without external powered hub etc.
Although it's probably not recommended to power the thing with 5V if battery max voltage is around 4.35V of whatever. But it survived like that for probably a year until I decided to do some changes to my setup and, in the end, switched to raspberry pi.
@@RoterFruchtZwerg please explain
Your capabilities far better than you think.
Lots of creators learn about IC internels and electronics and applied physics by watching your homebrews.
You are GreatScott.
Thanks for your contributions.
The complicated structure and circuits of modern devices I think scares many of us electronics hobbyists, myself included, from venturing into the topic of modifying or even examining them. The fact that you have done that truly shows smarts and is super nice. Great video as always.
Funny, I was looking into doing this EXACT thing with an old Nexus tablet so I could use it as a Home Assistant terminal. Good to know someone's done 99% of the work!
I wanted to install docker on a phone for this, but it seems to require kernel patches at which point I gave up. I am really confused why it isn't easier or more common to just flash a phone with a regular Linux distro GSI image. Phones are now more powerful than the home servers I'm considering, and they consume less power.
Didn't even think of that! Thanks! I have an original Galaxy Tab (yep.. the first one!) that's still running fine except for the battery life. Perfect use for it, since I just started my Home Assistant journey.
I have been trying for weeks with a Psion Netpad. It's similar issues from 2001. I think I got it when I hit the right numbers. The video gives me an idea or two more to explore.
@Rex Sceleratorum yeah but phones aren't ment to sustain running at full power for extended periods of time because they thermal throttle because they don't have cooling fans.
@@xxzenonionnex7658 There are two factors here as I hinted at. One is performance per watt per cost. Phones tend to lead here because they are made on the most efficient, advanced nodes and are still cheap because of mass production.
Second is raw performance. Phones certainly cannot beat the latest 200W TDP i9 chips. But for an always-on home server raw performance is not the highest priority compared to energy efficiency.
I don't plan on running my home server at full power for extended periods. In fact my current server (Atom processor) sits at near 0% most of the time. As it should. If an SoC has a temperature problem, it can simply be throttled in the kernel and still give you more than enough performance.
i laughed so hard when he said s10e "old". I'm writing this from my 8 year old sony xperia m5 and it still works fine.
Well, for me it is my "old" phone. But yes,....not really old at all.
Yeah, I was thinking about buying S10e, S10 or P30 Pro in 2020. Still with P30 and I consider it as "new" :D
@@greatscottlab whyyy it's such a good phone I use a s10 but the s10e is just as good imo and still relevant to this day I'd rather use a phone that's worth £20-40
Ye I actually bought a nexus 7 (2013) recently and it still works well for media and light gaming
Also do have it flashed with asop extended (8.1) which runs better than the last official update of android 6
Yeah That's great..i did this same project about an year ago with samsung note 5 to integrate the device with a OBD2 powered vehicle bus can ..i did use this device in my car as dashcam , gps tracker,rear camera monitor and all obd2 related value as well sensor values... I watched all yours videos since the first semester of my engineering back to 2016..you are always an inspiration for me..👍👍👍
That’s cool, any write up for the project?
Thanks for the feedback. Great story. Glad I could help you :-)
How did you do that your note 5 .
I want to do on my note 4
I had the same experience with an old tablet that I wanted to use as a wall clock; however, I found a different solution that I think you might appreciate. I saw that my tablet did the same strange countdown to 5% battery with a power supply acting as the battery. I tried a regulated switching supply and a regulated benchtop linear supply... same strange countdown. Then I determined that if I could fool the tablet into thinking there was a perfect battery installed during POST and then remove said battery when the operating system started, that the tablet no longer believed that it needed to charge anything. The result is the tablet reports that it is, "Plugged in and no time is spent on battery."
The solution was to short the red and black leads that would connect to the battery during POST and then open those leads when the operating system starts, and it is happy ever after. To short the leads I just installed a "push to make" microswitch in the body of the tablet. Now whenever I need to start the tablet (say from a power outage) I just have to hold that switch while the tablet goes through POST and release it when I see the android system starting. This method has the advantage of no additional circuitry required and there is no charge/discharge cycle happening.
ua-cam.com/video/WGsxnCSfmpo/v-deo.html
can you please elaborate on the red and black leads shorting? shouldnt it just make a short circuit of the power supply?
@@theoneohmresistor My understanding is that the BIOS of the tablet sees a "no internal resistance a battery" because I have shorted the wires. It doesn't short the power supply because there is no signal to the processor to try to charge the battery. To put it another way. As a battery loses charge its internal resistance goes up. This increase is the signal to charge. Of course, it is just a theory, I could be wrong.
Actually, this response got me thinking about it some more so I decided to discuss it with ChatGPT4.
After some discussion ChatGPT said the following, "You are correct that the tablet must have some mechanism to initiate a charge cycle, but this mechanism may not be as sophisticated as it would be in more expensive devices. The tablet's firmware might be designed to handle situations where the battery is connected and providing a voltage within a certain range. When the battery is disconnected, the firmware could be interpreting the lack of voltage or other expected battery information in an unexpected way.
It's possible that when you shorted the battery terminals during POST, the tablet registered a connection and assumed a battery was present. After you removed the short and the tablet proceeded past POST, the firmware might have encountered an unusual or undefined condition where it didn't receive the expected battery information. In response, the firmware might default to assuming a fully charged battery and not initiate any charging cycles.
The fact that the tablet reports a 100% charged battery and indicates being plugged in, supports this theory. The firmware might not be able to distinguish between the absence of a battery and a fully charged battery, leading to the unusual behavior you observed.
Ultimately, the observed behavior is likely due to the combination of the tablet's firmware design, hardware design, and the unique conditions created by shorting the battery terminals during POST and then disconnecting them. This workaround may not be universally applicable to all tablets or devices, and the actual reason for the behavior might require a deeper investigation into the specific tablet's design and operation."
So, the long and the short of it is... it is worth a try. It may work for your situation or not, but "no harm, no foul".
I’m a little scared to try that on older devices. I have once accidentally shorted the battery terminals and it would simply spark and short the power supply directly. Nothing broke but the phone didn’t want to charge, it gave a warning pop-up when plugging the charger in. It may work on some protection circuits but I think it’s a risky approach. I would assume most devices require the middle pin to have a signal for safety reasons. Chatgpt unfortunately isn’t the most trustworthy source, it is always super convinced that it’s telling the truth and tries to convince you that it’s correct, unless you show that it’s wrong, then it may admit that what it said was false. It can be annoying sometimes and I don’t fully trust chatgpt anymore after catching it lying multiple times, and when I would say no that’s incorrect it’d always go “oh yes you’re right, here’s the correct response”.
@@waldojuarezI don’t think the bios regulates charging, there is usually a dedicated chip for that.
The old PDAs had fancy desk stands that worked on mains power (and charged batteries). Many stands were heavy, stable and perfectly angled for viewing. Look at the Palm & Dell Axim for examples that could be modded or used as inspiration.
Or you can always 3D print one or get a friend to do it for ya.
This... this is actually amazing! Probably the simplest video that I saw from you but that delivers a huge value to us and the environment.
I was actually looking into this this very afternoon, and now my favorite electronics youtuber releases a video about it, thats special!
Glad I could help :-)
With this schematic I think you could use the existing usb plug on the phone to power the whole thing. Just tap off the 5v from it (from the connector or the board) and running it to the diode circuit should work right? Would save the hole and extra wiring.
It's an awesome idea which I wil definitely do to the phones I keep around to test websites and apps on.
Yep you could - I did this with an old Nintendo GBA SP. Wired a diode from the charging port to the battery terminals to drop 0.6V and I also removed a surface mount component to stop the charging circuitry from becoming active. Turned it into a USB powered (with the right cable) GBA SP. No need to make holes in the casing.
That won't work, for 2 reasons:
* The USB jack doesn't necessarily carry 5V. Modern phones use USB PD and will negotiate a higher voltage from the power supply. Furthermore, there's a brief moment (several hundred ms) before the power supply switches to the new voltage during which the power cuts out completely, with the phone being designed to run off battery for that period.
* You could make it a noncompliant device and just assume it will be plugged into a legacy USB-A power supply to avoid that problem since it will always output 5V. However, USB doesn't supply enough current to power the phone. Legacy USB supplies at most 1.5 to 2 amps, which gives
@@fat_pigeonhen you can simply use a charger that doesn’t have data wires so it can’t negotiate. If you want to mod the phone to work battery less you can also just keep in mind that not all power supplies will work properly.
I was thinking the same, you can either wire it up from the charging sub board at the bottom, and I noticed on some phones it directly deliver power to the battery connector even when not battery is present, and only starts regulating the voltage when it notices there is power draw from the battery. Maybe you can wire the power from the battery terminals to the pads on the battery circuit where the battery cell should be connected. That would let you replace the battery with a small modified circuit so you can close the phone and unplug the cable to put it away but als let’s you use the phone, but the same way you can use a laptop without battery as a portable desktop computer. And best of all you would be able to still hold the phone in your hand and you don’t have to break anything. The battery itself should be stored in a dry environment and not too hot nor too cold.
@@teamredstudio7012 sounds cooler, so all you need is solder the diode between the battery positive pad and the output from the battery terminal (I've measured on my tabled and there is constant output there). This is way cleaner
You can probably fix the old phone by reflowing the power management chips with your hot air gun. It's a very common failure mode for modern devices that the tin BGA solder joints fail from thermal cycling. Fun fact military and aerospace only use leaded solder to significantly improve reliability because lead free fails far more easily.
Yes, with lead better, but more toxic.
@@MrGeri95 Toxic for whom? The amount of solder used in a smartphone is utterly tiny and if properly disposed of none of it goes into the environment.
Besides there's much more toxic stuff in the battery if a phone is disposed of incorrectly. I'd gladly take a lead soldered phone that lasts for ages than a lead free that needs throwing away after two years.
This would have been the perfect test bed for a DIY super capacitor battery replacement. They are fairly simple to make, and could be made to fit exactly into the battery well.
Super capacitors are too unstable and too big...they will work only a few minutes. This is why no one use it unless you want burst power or something to back up an existing battery
@@Tailslol who says super capacitors are too unstable or too big? I think you need a bit more study time. I have made one myself that was around 8F @2.7v and smaller than a normal cell phone battery.
Sure it wont contain the same energy density as a LiPo battery, but it will fully charge in a matter of a couple of minutes and works amazing as an energy storage from a small rectified generator source.
Im sure that in the space in a smart phone, a super capacitor of around 25-30F could be made. This would run the phone for an hour or so and only need 5-10 minutes to fully charge.
@@TerryGilsenan clearly 5min is not enough and you should show what you did because i studied a lot those and they are far from ready in everyday use. and way too expensive.
@@Tailslol expensive? I made supercapacitirs for around 50cents each. That's cheaper than any battery you could buy.
@@Tailslol 5 mins of charge time for 30-60 mins of run time, is pretty good.
Awesome! Still at 1:50 but now you're talking about powering devices without their batteries, I'm pumped! This maybe great with my unused phones/tablets to create dashboards for Home Assistant around my house😎. Thanks!
You are welcome :-)
@@greatscottlab incredible I would like to congratulate you for the video and for sharing the knowledge I have an nvidia shield k1 tablet that is very capable, it emulates many things and very fast it even supports streaming of games fullhd movies but its battery does not hold a charge anymore I put a stepdown regulated at 3.7v 2amp it works However, the supposed battery runs out even when connected to the power supply, I will do what I taught in the video, I would like to know if I will be able to use the charging port with an otg cable because the idea is to use the tablet without battery and with joytisk usb to play, because currently if I plug a cable into the charging port it turns off
I've got a Samsung Note 4 which had all the same issues. Replaced the battery, never worked properly. The battery expanded and popped the back of the phone off.
I wanted to use it for video recording, but as per Great Scott's video, when you power it up, it goes into an endless boot cycle.
I might consider building this one day - but it does make the phone look kind of messed up !! 😄
Have to see which Android i 'had'; Mine did Same thing. Trouble for Years, with NO answers to why.
Shutdown with Full battery - registering -0- Charge. I found out when Phone 'Opened all by itself. *8{|*
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I did something similar with my Sony Ericsson Xperia Ray. I just plugged 5 volts straight to the battery terminals. It worked just fine, no battery level drop.
I used it to record time-lapse over a period of a week or so. Worked out great.
The whole Swollen battery "Issue" is VERY blown out of proportions. Not only is it NOT going to happen to any phone that is being used it can happen to ANY phone left unattended for a very extended period of time. I have recently repaired an iphone x with a bettery so swollen the display was completely detached from the rest of the phone. It is recommended to charge the phone to 60% before storing the phone and charging it up to 60% every few months to maintain the battery.
This is something i would do after i get fedup of my phone dieing in mid of a game🤣
But honestly this is some nice modification because it reduces e-waste and provided many advantages like home security you mentioned above
Great job🙂
I think so too :-)
This is exactly what i did for my Samsung Galaxy Tab 4 7.0 3G Released in 2014, I tried purchasing replacements but both only lasted a year so the moment it showed signs of bloating and decay for the second time I took the brains of the battery and attached a USB cable on it and placed a hole on the side then I used a 2A Original Samsung power adapter to power it.
Now then, here in Asia gadgets are hella expensive, and the second hand market here lives in Facebook marketplace and in my experience with listings there they're not managing their listings, leaving already sold items unmarked and them sending you promotional nonsense or product offerings, which made this decision a good choice.
One thing to note before doing this, YOU NEED A HIGH QUALITY ADAPTER, here in Asia, cheap quality power adapters supplying less than 1A of power and even if it does the thing heats up to the point the case is as hot as a mug of hot tea, so make sure you got a good one.
@@greatscottlab Can you do it for an iPhone (:
I wish people would stop talking shit about e-waste.
I believe you can run a simple server inside, and install Pi Hole in it. With rasp Pi is still hard to get, I can get tens of good specs android with cracked screen cheaply. I can control it with scrcpy for setup, and having it with no battery reduce the risk of getting exploded.
Great project!
Only change I would have made is soldering the battery lines to the inside contacts of the charging port, and using an adjustable LDO to solve the 9V USB-PD problem. Unfortunately requires microsoldering, but that way you can keep some of the water resistance and don't have to cut the chassis.
Yep. I thought about that but the hard soldering is probably not suitable for most viewers.
I would have done that too, except I wouldn't bother about PD charging cause, there are adapters with only 5V and cables that doesn't have data wires.
@@greatscottlab Absolutely correct. It would definitely require a microscope. I just love "seamless" modifications haha.
@@NiceEyeballs Ideally, you should make it safe to use any adapter with any cable without blowing up the phone. Don't set traps for yourself. If you add an LDO to the battery circuit, it will be tolerant to PD voltages. That way, you don't need to mod the chassis or use particular adapters or special cables.
I don't think the charging port can carry the necessary current to keep the phone stable. This is why the phone still starts up with only the charging port connected and no battery, but reboots as the voltage drops. Even the current setup he has is probably not going to be 100% stable, as it's running off of only one USB port, which is unlikely to match the output of a battery in all situations. To get 100% stability, I've found I have to use two USB ports, one wired directly to the BMS, and one plugged into the charge port.
Usually capacity measurement is done by the "BMS" board that is attached to the battery. Otherthan than the main power lines, it has 2 more wires (probably i2s smBus). You could find the shunt resistor in the BMS and by shorting it, you should be able to keep the battery level not dropping down.
How would I go about finding the shunt resistor?
@@nnamerzyou could look for the BMS chips datasheet; from there you could find where it would be connected to, and the recommended layouts included are normally a big tip off
Phones don't have a BMS on the battery and definitely don't have any shunt resistors. They're single cell. No shunting required.
The chip on a phone battery is just over-current and under-voltage protection. The extra pins are usually a basic thermistor for temperature estimates so charging can be shut down or slowed as the battery heats up.
@@tin2001 sometimes on 4 terminal ones have all
ua-cam.com/video/WGsxnCSfmpo/v-deo.html
That's great, but the problem is that Android has a power manager driver. It thinks that there is no such thing as an infinite battery and the percentages will drop and the phone will shut down. If you turn your device off and on again, everything will work again, but it will not last long, after several such reboots, the phone will not turn on at all, because the driver will think that the battery is broken.
And of course you can also power it with an external battery based charger so you could use it portably.
I wonder if you could also add a small capacitor in place of the battery so you have a few seconds to switch power sources without rebooting the phone.
Sounds like a fun idea. But I would at least expect a supercapacitor to do such a task.
@@greatscottlab I was thinking the same thing. (By small, I meant physically, since there's limited space).
@@greatscottlab if you use a capacitor, it may not need a cable loop.
a better idea would be put a small voltage regulator inside and get the voltage output of the usb this way it will not need holes for cables and also make sure the voltage is ok
also theres a battery protection option that forces it to not goes above 85% just enable it and plug it in when needed to use it as a fix device
This is awesome, I've been using old phones as media centers and gauge clusters in project cars in a modular fashion but always worried about permanent versions using recycled droids. I just figured all lithium cells became the spicy pillow sooner or later.
🤣"Spicy Pillow"
Keeping that.
Another option for always-on phones (though may not work forever) is to use a rooted kernel & charge controls via an app to let it sit at a non-100% charge. I find this causes much less swelling.
Can you explain me little more about it? I want to make it like that
That shouldn’t be tried on a working battery, pulling the voltage lower than the minimum voltage will cause the batterie’s internal resistance to slowly rise due to crystals growing inside of it, basically killing the battery slowly. I have had a MacBook battery swell up within days of being discharged completely. That made me believe discharging batteries increases the chance of it swelling. I have also heard it’s possible to completely drain a battery to around 1 volt to keep it in long term storage, putting the battery to sleep but I don’t know what to believe since the internet gives counter intuitive information. Would it be possible to use a modified kernel and then simply disconnect the battery and only plug the in the circuit itself?
@@teamredstudio7012 Optimal % isn't low at all, it's high-ish, just not brimming on 100%. I.e. 60-80%.
@@xvii_au yes, I store my lithium cells at around 50-60% for long term storage, in a dry space because lithium loves to react with water and release nasty gas.
This is an amazing hack, and I can give you some advice to be able to use it with any cable without making a hole in the shell :
- You can look for the USB-C connector and cut all trace for D+ and D- / CC1 and 2 / SBU2 to be sure phone can't enable fast charge by any way
- Next thing is solder 1 wire into VBUS pin.
The result will be clean, but you need some micro soldering so it make the hack a little more difficult, bad thing is you lose the connectivity with any device thru USB :(
Great find about the software calculation of battery life remaining! This has a potential of software fix for many battery problems.
It reminds me of my modification I did in a Samsung tablet. It had a very weird connector that I haven't seen before, and I didn't want to buy an adapter. So I designed a 3.7V battery charger board powered via USB, created a hole for the USB port in a tablet's housing, and somehow fitted everything inside. Charging works, but the battery level keeps dropping, so every time I have to wait till the tablet shuts down due to the "low" batery, complete the charging process and power it up, so it can realize that the battery is actually full. Just for fun I'm gonna short the current shunt and see if the battery level will freeze
Shorting the current shunt sounds interesting :)
@@Wrublos212 I've shorted the shunt but... nope, that wasn't it. The battery level continues to drop. I think that one of the power ICs provides the data about battery usage, so I would have to hack the system or modify those tiny circuits, what I'm not capable of
@@Wrublos212 Well, actually the battery level dropped only by 1%, and the tablet went wild. More demanding apps were causing system crashes, tablet seemed to work slower
Same problem I'm having. I'm curious to see if you find a solution for this.
Did you ever manage to find a solution? I'm in the same boat with a Fire Tablet I wall mounted.
This is crazy! I was literally thinking about doing this! I have an old Samsung S9+ that I wanted to use as a dash for my truck. But I was afraid of leaving it in my truck due to the battery. Thank you for making this video!
Yea but it would have to restart every time you shut off the engine. Unless you have cig ports that stay live all the time. Then it would drain your battery
@@isaiah4478 I have a 12v 2280ah lithium battery for my truck, so it would never drain it.
I miss the days of the plastic back covers that could be removed super easily along with the battery being removable
Great recycling project. 2.0 idea - could you tap the USB to power internally and power your "battery circuit", thus removing the extra wires and power supply?
If you are good at soldering - yes. Generally you need a lot of flux and steady hand
That won't work, for 2 reasons:
* The USB jack doesn't necessarily carry 5V. Modern phones use USB PD and will negotiate a higher voltage from the power supply. Furthermore, there's a brief moment (several hundred ms) before the power supply switches to the new voltage during which the power cuts out completely, with the phone being designed to run off battery for that period.
* You could make it a noncompliant device and just assume it will be plugged into a legacy USB-A power supply to avoid that problem since it will always output 5V. However, USB doesn't supply enough current to power the phone. Legacy USB supplies at most 1.5 to 2 amps, which gives
@@fat_pigeon Thank you for this fantastic response. I read it a few times and learned a lot here. I am looking to fit a Blackberry keyboard from Tindie to a more modern phone so your post also helps point me in the right direction. Thanks again!
Interesting feature with the voltage - I did the same thing with Huawei phone and it reported the percentage based on voltage - changing the voltage even caused the battery percentage to go up :)
"Battery Trickery" varies by-manufacturer, and very old versions of Android dealt with batteries quite differently.
Excellent trick with the diode. Having converted one old phone with a swollen battery using this technique, more recently another phone started suffering from the same swollen problem. Instead of powering it permanently I simply replaced the built in battery with a slightly smaller removable battery meant for a different phone, soldering its + and - terminals to the old battery's reclaimed protection circuit board. Thus providing the old phone with a new lease of mobile life, including being able to operate it from the usual USB adapter.
for me, just replace the battery with super capacitor, and then you can use the fast charging feature although doesn't make sense, just for current spike(mostly will use the capasitor though)
I think should be possible. Not completely sure though. But supercapacitors is also kind of big. Not sure if a lid would fit.
I've done it with just ELECTROLYTIC capacitor (470uF or so) on Galaxy S3, so definitely possible. Although, the fact i've also added an LED with a dropoff resistor in parallel may have played a role, cause the phone is driving something constantly at low current there. Anyway, those phone ARE perfectly capable to just power themselves from USB, they just don't want to.
This is my thought also. Construct a battery eliminator from capacitors etc. to fit into the original battery space and connect to the normal battery tabs on the BMS board (extracted from actual battery). This circuit should act like a small battery, so plug the phone in to USB power and the apparently low charge battery (I.e. uncharged caps) will get charged up until sufficient to allow the phone to boot and also add a bit of a boost when required, just like an actual battery would. No additional leads into the phone which just works as it should.
Ideally the total capacitance would allow leads to be swapped from one charger to another (so just a few seconds) without the phone restarting. A minute would be way more than required IMO.
I am not concerned with any sort of mobility. I just want to be able to run old mobile phones/tablets for other purposes (clock, radio, HA screen, whatever) off mains/USB with no battery involved as that WILL eventually fail and expanding Li-Ion batteries in the house are to be avoided.
I'm sure this is doable, but beyond my abilities to fully design. However the intended result of an intact phone that powers purely from it's original USB input is worth pursuing is it not?
@@UKenGB Would love to see a videos about that!
This video is a perfect start for someone looking to turn their old phone into a home lab / hypervisor
I used the cheap lithium battery charger protection PCB's from china connected to a small capacitor bank to do this in the past.
Works well, it's extremely cheap and easy to do
Good to know ;-)
I was going to suggest that. :) It would have been a lot cleaner, and he'd just use the stock USB port.
The classic TP4056 that everyone has like 5psc of
This is fantastic. I basically did the same mod but ended up with a power supply for the phine and one for the usbc to run octoprint for my 3d printer. I wasnt sure why it needed both but now i do so i bet i can make it just one now! I will also be linking this video for anyone who wants to use an android with Octo4a for their 3d printer. Its almost mandatory cause i wouldn't recommend always charging a lithium battery all the time.
Literally an hour ago I threw away old swollen battery (Sony) and want to revive the phone to get back data from it. This video is tailored for my exact situation. I love such coincidences :D
Love it when I can help viewers like this :-)
@@greatscottlab Yes, you have both reach and impact throughout the world. And I was already capable of doing such modification because of all the other videos that you've made before :)
Thanks!
Very interesting!
Maybe the feature to limit the SoC to 80% (around 4,2V) can be working, it's over 4,2V that the battery life is seriously reduced. Also, I remaked that old phones with a low SoH don't charge the battery over 4,2V even when displaying 100%!
Yes. Modern smartphones with their internal batteries, do a lot of 'trickery' to guesstimate a charge state, and manage how fast the battery 'ages out'.
Example: Apple semi-recently was in hot water for 'gimping' old devices via OTA sw; their excuse being, old batteries can't deal with current spikes well, thus the throttling.
All this project and the Apple debacle proves to me is that we never should've 'allowed' smartphones with integral batteries. From both the eWaste and "Ownership" perspectives, it was a big mistake.
Solution then?
I was already using my tablet without a battery, it was nice to see this video, a lot of people were informed.
:-)
Did you need to do the fake charger hack too?
I don't understand fake charger?
I did as in the video, I used a diode or something
This is indeed a brilliant idea! I have personally encountered a similar issue where the battery icon drains even when the device is receiving a constant power supply.
what confuses me is that people seem to believe that this is a Samsung only problem, don't old Li-ion batteries always have the tendancy to swell up?
Did the watch the video of Mr who's the boss
Yeah they can swell up but Mr.Whosthe boss had a whole room of smartphones and if I recall correctly only the Samsung ones were expanded and it was a couple of them, not one or two.
They do. But Samsungs batteries are apparently WAY more likely to do so.
My Sony Z2 also had such a problem.
@@jost459 Yeh wrote it because my Ipod nano 4th generation killed itself by bloating up the battery (the screen gets smashed by the battery because they are so thinn) its also pretty known.
This video reminded me why we should buy easily repairable phones...
Thanks the idea with the diode is awesome I thought to shove there dc-dc. Only there is a problem with the battery protection it blocks the power if the voltage drops.
This video inspired me to do something similar! I had my old LG G5 that took a trip through the washing machine, I managed to save it, but the audio circuitry and battery were destroyed, I was shopping for a new webcam when I came across this video and saw my old phone just sitting there, and i decided to do this instead! The phone is now much nicer than any other webcam i could of bought, thanks Greatscott! (I did reduce the cables to just one cable however by just bridging the usb power into the charge protection chip of the old battery)
I've also done that with my Nvidia Shield Tablet in the past, after the first revision got recalled because of overheating batteries. Though as already some have mentioned I would also love to see an approach with super capacitors, to gain at least a bit of portability :)
I legit thought you diagnosed samsung battery problem or smth
But you made something 10 times better out of it, good sir!🙌
Thank you so much for this insane video!
Glad you liked it!
I found a great use for my old phone. It serves as a wifi router with LTE modem. I don't use internet that much, so by using mobile internet, I pay 3x less monthly. This modification is perfect for that use.
why not solder a couple of wires to the inside of the phone's usb port that go to a step down converter that is connected to the battery protector circuit? The step down converter would probably fit where the battery used to be and all cables would run internally, only using the original USB port to feed power in
I tried this but the phone seems to just boot loop when powering via the step down connected to the bms
This would be great for OctoPrint, either using it as a remote for another OctoPrint server, or as its own self-contained server. I love it.
That’s what I’ve been trying to do with my s7, but I need the usb port free to use otg,
@@TDOGGisawsome Yup been trying the same thing but haven't found a solution yet
I screamed internally seeing you try to pry that back cover. Especially because I work at a service shop. Never use a screwdriver or much force when working with glass backs, also NEVER use a screwdriver when prying the battery! It's a really high chance of it either exploding or catching up in flames!
Yeah that got me aswell ! Removing those batteries with a metal screwdriver is never a good idea !
Awesome work as always but imho there was no need for external charging cable, you could have soldered charging cable lines directly to charging port internally, hope you undestand. Its just a suggestion
I did that same thing to my phone cuz the battery was busted and i was wondering why the percentage dropping while it was supplied by power supply thankfully u helped me to know 👍
Thank you so much for sharing, it will be very useful!
My Zenfone 5Z battery uses the same connector and died a few months ago. There's no more support from Asus, it's like throwing away an entire gaming PC because the power supply burned out. It's disgusting to see the direction that obsolescence has taken, I don't have the money to change my phone every 3 years.
Hugs from Brazil. 🥰
I was writing a comment while you mentioned it. I think it's stupid that the phones don't measure the real Voltage. I did the same with a Galaxy S3 and also came up with the same solution, It's working fine for over a year now. I use it as a timelapse camera in a grow box 😊
Agree, this went from nice, it's really easy to maybe but it's kinda junky/needs more effort very fast
@@n27272 It depends on the phone - I did this on a Sony Xperia Z Ultra, and the phone did not shut off when it hit 1%, just stayed there forever. However, it would occasionally reboot (~once a week) as a single USB outlet was not enough to power it under all circumstances, so I had to also plug it into a second USB outlet via the charge port to have 100% stability. I suspect he will also have stability problems using only one USB port, but that probably depends on the power needs of the specific phone.
@@iguanamoat did you connect it straight to a 5v power supply?
@@n27272 I added a USB C port for convenience, but otherwise it's a direct connection from the old battery's BMS to whatever 5v USB power I plug into it.
Great I am not alone at 03:16😅
Battery storage capacity is around 60%. sometime even with that in mind, batteries tend to swollen.
It is great that some recent phone allow to "Pause" charge, and use current directly from USB port, this way is protected from constant charge, and not drained.
Would it have been possible to take the 5V from some internal pins near the USB port instead of drilling a hole in the frame?
No, for 2 reasons:
* The USB jack doesn't necessarily carry 5V. Modern phones use USB PD and will negotiate a higher voltage from the power supply. Furthermore, there's a brief moment (several hundred ms) before the power supply switches to the new voltage during which the power cuts out completely, with the phone being designed to run off battery for that period.
* You could make it a noncompliant device and just assume it will be plugged into a legacy USB-A power supply to avoid that problem since it will always output 5V. However, USB doesn't supply enough current to power the phone. Legacy USB supplies at most 1.5 to 2 amps, which gives
I had a similar retrofit for moto g 6 plus a year aho. Ths phone killed two batteries in a row and was replaced by a new one. So I also cut off the bms board from the battery and used it to imitate battery with cheap buck conerter. Worked out fine and I had no need to imitate charging. So it is definitely a vendor/model thing. The device is still alive and in active use by household members.
I would love for someone to make boards for different phones and tablets that also hack into the charging port for a flawless exterior.
Ebay or Tindie would be good places to sell such things.
He should try to replace the battery with capacitors (maybe ceramic). This way the internal charger will still work correctly and you can power it through the normal USB-C port.
Like a mod chip. Samsung spends millions to make sure you cant be rooted and to make sure your phone cant be used in such a way coz capitalism.
cool, but meh... We been doing this for a long time round here but I would have done it alot differently. First off, why loosing time drilling through the phone, risk dammaging its lcd, having to endure a "trick-charge" usb c plug and the dull look. You had the phone all dissassembled, usb-c pinout are easy to find online. knowing that, you could have ran two kinar or even enameled wires INSIDE the phone itself for the trick charge... this would have not only saved space, risk and time, but also the use of the usb c cable, and the fact that if you want to use the usb wether for pc or OTG stuff, you now have the battery counter running again agaisnt you and even risk damages to certain pc, espcially the first usb 3.0 compliant hardwares... Still a brillant idea to limit e-waste, but from you Scott, we normally get project that are fully and well thought. this one feel like you might have rushed it and used less neuron than usual, maybe you were tired and they were set a neuroff? hihi < pun aside, you do amazing job entertaining us
How about connecting a 3.7v rechargeable button cell to the battery pcb? You would still need to keep the phone plugged in but it would simplify the wiring.
Even capacitor could "imitate" the battery I think.
This sounds like a bad idea to me, cause the phone circuitry is designed to charge WAY faster than this cell would take. Wouldn't that create a mini-bomb ready to explode?
@@borislipschitz2740 I didn't think about that... Maybe a capacitor (as Wrublos212 said) would be a better idea.
Slick video captain! Interesting so many folk have had swelling battery dilemmas. I currently have the Notes: 2 (Shelf), 4 (Shelf), 5 (Shelf), 8 (GoPro video editing), 9 (Daily DeX), 10 (Daily Phone) and fortunately I have not experienced that with any of them.
I'm detecting a problem here.
Some of the chargers I've used actually output 5.2V, highest I've seen is 5.3V
If you use it with one such charger, and the voltage drop is only 0.6V at that point, you could give 4.6V into the phone.
Wouldn't that damage the phone?
Unlikely. But still possible...
Voltages of over 4,2V in Lithium bateries are hazardous. In best case destroying batery if not bursting them in flames.
Lithium bateries are most sensitive on overvoltage of all.
i have a Motorola charger that gives 5.2v at the output, even thought it says 5v 2A its fine as usb standard has +0.25v max above 5v at the usb charger Port this extra voltage its used mostly for cable voltage drop which is about 0.1v per amp, also i have a charger with 5v 3a rating that outputs 5.32v a litle bit above usb standard but also fine for devices with battery charge controller wich can handle up to 6v, it have fried 2 chinese speaker that has no ic to manages input voltage to battery ,also have fried another one of then by inserting a quick charger thinking it will be fine.
I looked through the comment section here. Others reported that they use straight up 5V at the battery pins. No problems.
The current would begin rising, and the diode would start dropping more voltage, so it might balance out.
The thermistor is in the wireless charging coil circuit which I see you didn't even bothter plugging it in.
Its draining because it doesn't detect the thermistor.
Your diode solution is only needed for the battery for 4.3V.
But now the USB-C cable is free! 😀
Do you think while using this method to keep it on you can add a USB type A connector connected to the + - and data pins that are going in the phone with the idea of using USB Flash drive or OTG for pheripherial devices ?
Hmmm not sure. But sounds possible.
@@greatscottlab I have this idea for a "media player " for a car with an aux FM transmitter connected to the audio jack of the phone the phone itself powered by a 12v car phone charger and use flash drive for the music . Was wondering how the powering of the phone would work but your video came just in time to save me a lot of headache :)
@@greatscottlab otg works?
Mine DID! I kept Asking WHY Phone w\ Fully charged Battery suddenly SHUT Down, registering -0- charge. NO answer.
For years, Phone Temperature would get HOT at times, but not all times when it shut down.
LOL NO need to Heat phone to Remove back, Battey did that for me. THAT's when i realized what was Wrong. {{sigh}}
*SO Glad* there's at least *One on this Plant* that figures out How to do this. This was *Interesting* to see. *THANKS!*
This is a nice little "hack" but people should note that this solution might not work with all Samsung phones because this depends entirely on the firmware of the phone and/or what signals are connected from the battery pack to PMIC. This worked mainly because you were able to separate the BMS from the battery and the battery only utilized only power terminal and ground connections.
The reboot loop you see at the start of the video when Scott tries to power only on wired connection is completely a firmware protective feature. When the device initially boots up, it initializes all the ICs and, assuming it was properly designed, will have built-in checks for this. This is just how the device's firmware handles this particular failure mode. Since its a mobile phone, obviously the primary intended use is battery power so its expected behavior. Also, in my personal experience, I've seen this type of behavior with some laptops where they prevent use of the device without a battery connected.
Just my two cents as someone who develops embedded software/firmware for battery-operated consumer products.
I have some experience doing this with a few phones. Here are my experiences:
For a Samsung S duos, the phone works quite happy receiving power through the battery connector (I used a diode to lower the voltage from 5V). But it would not like to receive power on the usb port at the same time. Conecting it to the pc resulted in a lot of spam of the battery not working or something like that. This phone was my very simple little server for a while.
An Allview P5 Quad - bad experience. Would really not like not having the temperature pin voltage set (could be done with a voltage divider). Also, no usb power or else it would definetly not power on. I had a beefy 5V 4A power adapter, but without some beefy caps on the battery connector it would act up/randomly reboot or simply boot loop. Also, it died some time later.
Allview E4 - beefy caps or have the usb connetor power as well. This phone had otg support and I managed to root it so I had plans for that otg support. Because it uses more power sometimes I intend to use a converter instead of diodes. But this one works well with or without usb.
Allview V2 viper - has no otg support unfortunately. I don't remember the details, but I don't think it works properly without power on the usb port.
Samsung s3 neo - doesn't work well without power on the usb. It "discharges" as the phone in the video. Also, best results with caps. I also think it doesn't like to work without the temperature pin set correctly, don't remember, also I had lineage os installed on it, so I don't know how it works using the stock ROM.
Hope this helps people. Also, haven't noticed until now how many phones I tried this on.
Also, surprisingly Nokia 3310 - not exactly with a supply. I found one without a functional battery and I found another smaller phone battery that would fit inside. Unfortunately the phone wouldn't be happy just with the power pins connected. I had to add a voltage divider for the temperature and another to set the battery type. It has 4 pins: +,-, temperature and battery type. Apparently the phone could have different battery types and would use a pin to determine the type. I found the values online and used that.
Thanks, this is exactly what I needed for my IP cam system, using old android phones to monitor my cats and my 3d printer through the internet. :)
At 3:08 I yelled "oh no please don't" 😅
Oh Yes! ;-)
This is a pretty usefully hack for upgrading cars with old head units, this way you can get GPS and stream music without getting an expensive radio.
Could you instead replace the battery with a capacitor (or capacitor bank) and then continuously charge that using the USB cable? That way you don't have to hard wire the phone or cut holes in it for the wires.
This would probably work on a limited basis, but under continuous/heavy use the cap will get drained faster than it can be charged and the phone will die or reboot.
theoretically, but you're also have to add some circuitry to keep it for charging/discharging too much and it'd have to hold enough power to keep the battery management software from cutting it off.
at that point, you might as well just put another battery in it.
@@InfernosReaper I agree that a battery might work better. Certainly a continuously connected USB cable should be able to keep up with the needs of the phone with a smaller battery than the original phone required.
The battery swelled up and popped the back off of my S8 about a year and a half ago. I took a chance and replaced it with a Chi-Com replacement from Amazon. Still works perfectly at this point in time. Cost was about $25 plus shipping. Should probably replace the phone with a new one, but I like to get as much life as I can out of my devices. Especially a device as expensive as a smart phone.
Did the samething with the same phone. 👍🏼
Great video! For anyone who's storing devices with LiPo batteries and doesn't want them to swell up, here's what I do that prevented my 3 Samsung phones from having this problem (one of them is a phone I bought back in 2015).
I charge them to 50% before storing them, and I take them out every few months to give them a full charge/discharge cycle, before charging them back to 50% and storing them again. This seems to help all devices that have LiPo batteries in them. I haven't gotten a single spicy pillow, yet.
Couple thouths and how I'm planning to do similar thing with my phone:
1) why dont you solder to the power & ground pins of type-c connector on the motherboard? this and using simple type-c cable without data line (cheap chinese cables) OR usb charger without PD feature (old apple ones and so on) would do the same, but without hanging wires on the side of the phone
2) next level (at least what i'm planning to do) - small buck converter in the battery compartment and now you can use ANY charger regardless of their voltage! 1S bms would also do the trick, they costs maybe 50cents a piece with shipping
it will be a little nicer overall. hoping you will make a follow up video with converting PoC device to something more finished
Brilliant, dude! Fantastic work! 😃
I really liked the ideas in the end!!!
Stay safe there with your family! 🖖😊
This is so amazing I tried it on my old sony phone and it worked but the battery percentage gets low even though it’s plugged in
This is likely a massive overkill.
I've powered an old Galaxy S3 (still got a removable battery and it DID puff up) without the battery by shorting the battery thermistor terminal to the ground (otherwise it wouldn't "charge") and hooking up a big enough electrolytic capacitor (later changing it to a bunch of small ones in parallel to fit in the battery compartment) to the battery terminals, and then hooking the USB charger as usual. I've even hooked up an LED with a dropping resistor to visually see that the phone is trying to "charge" the "battery". The phone keep happily staying in CV mode, charging my newly made "battery", thinking its at 100% charge and powering itself over USB connector and running till this very day.
This said, S3 didn't power AT ALL without my little trick, yours seem to enter the bootloader, and THEN powers down when simply powered without the battery at all, so its most likely possible to circumvent by software means alone. In any case, i'd totally try to just solder a capacitor to battery protection board instead of actually powering it through there, hoping my old S3 trick would work, lol.
I think this video is going to be your most viewed video after a long time Scott! supper one!!
I actually used this trick for an old samsung phone that it's battery was so weak that I can't get it to the bootup screen, Anyway keep it up!
That was a really good and informational video on how to destructively boot smartphones without battery but i much prefer editing some kernel files to make it boot with just usb connection with or without battery. Thanks for video
I did a almost identical hack with a old android tablet. I turned it into a digital photo frame, and dedicated Spotify player. Samsung phones make handy little desktop computers with Samsung Dex. You can plug a mouse and a monitor into it.
I was giggling like a child. Such a cool, clever project, and the diode is such an elegant solution to dropping the voltage!
I just came across this video while researching solutions for my old galaxy s6! I needed it for a klipper screen last night and found glass in my hand upon picking it up. Thank you for the help! Been watching for a while but subbed only a few months ago.
Maybe a more "tidy" approach like soldering from an internal 5V power source could work? If the phone draws most of its power through the usb-c port you could get away with a smaller wire inside. Or you could use a supercapacitor as a replacement for the battery to trick the phone into thinking it has one
I wanted this video for more than years . Thank you . I have old phone with battery issues 😐
Whatif you did all the power wiring internally? Instead of drilling a hole in the case for a modified cable, modify the actual port on the device from the inside. Pull up the data lines and put fingernail polish over them to keep from conducting with nearby pins or each other, while soldering leads off the power terminals.
Now, you have a phone that looks normal on the outside, can be modified back to stock a lot more easily, and the cable is now renoveable.
This kind of project has crossed my mind in the past with phones becoming thinner and thinner and battery life becoming questionable. I figured that some kind of ultra capacitor could be used in place of the battery in combination with some kind of external case/battery type addon to power the phone for longer.
This would enable the phone to continue functioning to some degree while you change the battery case and could provide a flexible solution for users that want more battery life at the expense of device size while restoring the ability for users to replace the expired/damaged battery prolonging the lifespan of the phone.
as for taking it apart, heat can be your friend..ifixit has a thing you can microwave and leave on your phone for a few min to warm it safely to help loosen adhesive
I did the same almost a decade ago with a Nexus 5 and LG F60. Nexus 5 had same issues of battery slowly going down despite being run on constant voltage. IIRC, LG F60 did not have the same issue.
I used a LM step-down regulator, which includes capacitors. Function would be unstable on most low rated chargers since the peak consumption was over 2A or so.
That's a lot of effort for something preventable with battery charge limiting, built-in or available after rooting the phone. I still love the approach, of course!
I've had this swollen batter issue on a Galaxy S7, S10, and a S20 all within a year or so from purchasing them.
I noticed then after I would use the phones to stream to my television for long periods of time with the otterbox case still on them. I don't know if it is a heat issue or poor quality or what. I've always assumed I mishandled them somehow and never tried to resolve it in the past. I just used them on wifi without the case after noticing this and gotten new phones for regular use.
I'm somewhat of a Samsung fan so I won't be switching brands. But now I can bring those old phones out and use them safety again. Thank you.
Nice trick for re-using in stead of re-cycling an old phone. Well done. May I suggest to wire the 5V on the inside to the backside of the USB charge port connector instead of looping the charge cable on the outside?
Can you explain how to calculate the resistor and diode value to use in another video or a summary description here? Thanks
@kennethz4466 and @greatscottlab I would also like to know. UA-cam shows there was a reply but it appears to be hidden.
1:32 used to work on older phones
i had tried to power up my old phone directly once long back..phone just kept rebooting..i didn't know this stupid battery percentage problem..thank you for revival of my project
Could get the voltage from the usb port
Unnecessary hole added in my opinion
I think the phone sometimes requires more than the USB can provide, therefore boot looping or turning off. And this might be related to internal electronics, not power source or cable. I believe a bigger capacitor on the battery end might solve this, but I never tested.
You could have connected to the internal USB and used a buck converter for the battery. No holes or extra cables.
for a long time, i finding solution for this problem, and here you are my great teacher with the simplest neat trick thank you very much for that perfect stuff