First thing I saw as I picked up my tablet was the notification of this video. That reminded me that I had a couple of 18650 cells on charge and I was not certain of their reliability. A quick voltage check suggests one of them is definitely a bit dodgy, I'm glad this video reminded me to take them off charge. In actual fact, the charger is a modified flip pin charger, pins removed because I didn't want to plug into a death adapter and a flex and UK plug substituted. The open circuit voltage is a reassuring 4.2v and although I couldn't check the transformer itself, everything else seems pretty well constructed so maybe they aren't all dangerous crap. Twin charger with separate control on each circuit.
Brilliant. I have the same charger but in a dual cell version and I started to question the reliability of them. You've put my mind at ease. It seems to be able to also charge the 3.2V LiFe 14500 cells and it knows to stop at 3.65V despite its 4.20V charging output. So more intelligent than I thought. Mine is a 1000mAH output version though. However, that could just be 500mAH per cell since it's a dual cell charger. I think they addressed the LED brightness in the updated versions as now they are plenty bright enough. I have a Green LED for full charged and Red for Charging status.
I like these low component-count designs much more than the old mains-powered ones with a dozen components. Less chances for the manufacturer to use substandard parts, on top of lower shock risk.
I was talking to a friend on the phone a couple weeks ago when he got a message: his house was on fire. He left a cheap 20AH 48V LiPo battery for his boat on a charger, outside. First the boat caught on fire, then the house. Total loss. Play safe everybody.
Clive has recommended stuff from Ebay in the past, like head torches, resulting in them selling dozens and dozens more after the video dropped. So that's not _that_ unusual.
Took a few times of looking up the data sheet, but I now do finally recognize the LTH7 IC silkscreen, since it's in nearly all my cheap self charging electronics.
Considering some of the cheap chargers that've shown up on this channel, I was seriously worried that thing was just going to put the 5 volts from the USB right across the battery, with maybe a token-gesture resistor. I was pleasantly surprised that it's got proper, relatively sensible circuitry inside.
Did you know, Clive, that Argos now sell singular Molicel P26A 18650s in plastic tubes? They’re in the _”fogstick”_ section. Really excellent high-drain cells with 2600mAh capacity and a stated CDR of 25 amps. I wouldn’t give them a load of over 20, though, for heat reasons in a high-drain application, but they’re very respectable cells overall.
You should be a Chinese Cheap Product Checker - you find so many cool features to point out (like better position of the capacitor / led resistor value)
It's fairly ironic that looking as something qualified as "a textbook design... actually pretty good" becomes a welcome surprise when looking at low-cost end-consumer electronics.
I have a few similar to this only they plug directly into a wall socket via a 2 prong plug. I don't know weather it was the type of battery I used or what but one of them blew up when I switched it on to charge, after that I never used them again and bought a proper li-ion charger.
The application note states the Earth Pad needs to be a large copper area for best thermal performance. Also the pin that is being used to switch the LEDs is limited to 10mA. Also note this pin is in fact a tri-state pin indicating 3 different states of the charging circuit. See the application note for details.
You're braver than I. I wanted to look into replacing li-ion cells myself, but after one that I removed hissed at me I'm leaving it to the pros. Unfortunately even places like Batteries + won't touch them.
Mine used to do that too but now i have learned to charge and discharge them at no more than C/10. Had no problems at all since then - even charge them on my bench supply (set for 4.2v per cell).
I bought a couple of similar chargers and I had to take them apart and bypass the spring with a wire. Otherwise the spring has too much resistance and results in the charging cut off at less than 4.1v. After the bypass the happily charges up to 4.17v and I've been using them for a couple of months without issue.
I've got a similar looking one that plus into the mains (Type A). It has the helpful label on the front that reads "Intelligence can be positive and negat I've charge quick charge, Safe and reliable". It lets me know at a glance it wasn't manufactured anywhere in the western world. I haven't taken it to bits yet, but I probably should before I do something silly like plug it into the wall.
Those are equal parts clever and infuriating in their mechanical design. I'm not quite sure why I have such an aversion to that sliding contact, but it is very clever.
With only 2 resistors per unit and only six different component types (if I counted right), adding a seventh reel is probably cheaper than adding a third resistor.
they're commonly using the tp4056 chip which IMHO is somewhat better because of up to 1A charge current possible, so I guess this one must be cheaper. On the other hand here you get the 18650 holder as well, not just the PCB, so in terms of DIY this charger is probably a better purchase.
I ripped out all the electronics out of the mains version of this charger and put in a TP4056 charging board. The original electronics is dangerous and would overcharge the battery.
@@RedwoodRhiadra £16 but is a lot more useful. The vc4 is the normal charger, the v4s does a full discharge charge cycle with capacity testing along with being just a charger
Clive, video idea: how charging is handled in devices that are in use. I've been trying to figure out how that's done properly and having a devil of a time finding good resources.
The simplest method that comes to mind which isn't garbage, the charger supplies constant current to the battery terminals until a max voltage is reached, then shuts down until the voltage drops to a restart level. Actual charge rate is reduced by the device load. Depending on device current draw, a modest time delay between charge shutdown and restart may need to be enforced.
if the current setting resistor values give the same charging currents as in the 8 pin version of the chip, 1.2k is what you often find in power banks, which gives a charge current of 1A. 1.5k would give you about 750mA. 1k would give 1.2A, which is probably a bit too high. the formula is I = 1/R x 1200
I'd have used pre-1982 copper (bronze) pennies. Better conductivity. However, I've even used nickel plated neodymium magnets to extend the ends of my 18650's, with no problems.
I have a very similar charger that came with a flashlight to charge the 26650 battery and it seems to work just fine for the two different batteries I charge with it and I've been using it over 2 years with no issues. It will typically charge a battery up in about 2-2.5 hours depending on how much I drain them. I just plug it in an old USB phone charger and won't plug it into a computer.
I have decided I really like the 3 AAA flashlights because in a pinch you can cut any usb lead and put positive to one end of the pack negative to the other and you have a crappy nimh charger.
That's not regulated. Unless you're talking about powering a mobile phone (where its own power input and battery would regulate power) it wouldn't work very well. You could trim one of the led outputs and use that to charge, but it would take a long time!
2:22 You're measuring 460mA between the 5V USB charger and the battery charger. To measure the charge rate you should be measuring between the charger and the battery.
Would make no significant difference, as the charge chip uses a series pass element and its own current consumption is insignificant compared to the current going to the cell.
True, but you can work it out to be 540mA at 4.2 volts, so it's most likely going to come in at half an amp or so for practical purposes. That's about where you want to be for an 18650.
@@Chris_the_Muso - there is no inductor, so how do you get 540mA? With a series pass element regulator, the current input equals the combination of the output current plus the current used by the regulator itself (which is likely to much less than 15mA). The charging current may be higher if the input voltage is nearer 5V and/or the cell has a lower state of charge.
@@Mark1024MAK Ohms law, with a nod to the power law. Actual charge current will be higher than the draw current since it's essentially a CV buck converter, whether or not there's any kind of inductor in the package. There will be some losses but it's not significant, not for a $5 charger anyway. S'not an Apollo mission. That's why Clive said "about 500 mA".
He's on Patreon, so I'd guess one of the benefits to patreon supporters will be access to videos early. When it says the video went up 10 minutes ago that means that's when it was made fully public, it could have been on youtube for years, only accessible to those who have a direct link to it.
Maybe that's when Thier post bot was initialised lol. (or for some reason YT posted the time signature from the poster's source, not from its own server clock)
This looks like the one I got "free" with a electric precision screwdriver, it charged the battery once and then maybe coincidence but the screwdriver stopped working seconds after I put the charged battery in and didn't work with any batteries.
Probably coincidence. The screwdriver was probably worse quality than the charger. You could most likely pull it apart and fix it, but the real trick with those small screwdrivers is getting all the cogs back in the right places. The electronics are probably quite simple however.
Had a "homefire" branded 18650 make a pretty impressive bang recently while charging. Shot hot black debris all over the carpet and filled the room with smoke that would be useful for riot dispersal... Saying "Never again." would be redundant.
@@simontay4851 Most likely scenario. May have also missed a ding in the cell. The charger is still fine. Shuts off at 3.8ish The cell is pretty far beyond reconstruction. The whole thing was less than confidence inspiring... I dislike mysteries
I like how simple this is. What is the common failure mode of this chip though? Could it potentially overcharge the battery? I try to never leave lithium batteries unattended while charging, however i do forget some times and leave my flashlight battery plugged in at night. I do try to keep it clear of anything combustible, just incase. I also use protected cells. But redundancy is never a bad thing when it comes to safety.
Redundancy is always good. I'm not sure what the failure mode of this chip is. Going short circuit is possible. That's where protected cells have an advantage.
@@bigclivedotcom Interestingly this prompted me to take a look inside my 2 instances of this charger. They do have Red and Green, Charge and Charged led's but also an A1sHB p-chan Mosfet on the output of the LTH7 charge controller, Ground and Positive O/P.....
Hi bigclive i would have been interesting seeing you improve the LED as you say if can be done. Because i oneday want to start to building some things so i learn from you myself.
So, erm, am I right in saying that because there's no diode on the charging output side, it doesn't have any safety against putting the cell in the wrong way round? (Potential for Lithium meltdown)
If you can find them cheap enough they would be good for Home Brew cell charger dischargers using the spring cell contacts / terminals. Say a dozen or more.
Nah, need space for comparator, need more resistor dividers for voltage references... That's definitely too much work for someone that puts 2.2k resistor on LEDs to save on BOM and Pick and Place... 😁 Edit: probably would also need a double layer pcb or thinner traces to go under resistors, you know how expensive that is??? 🤣
I just got one via Amazon to review that's nearly identical in appearance, altho it has a permanent USB A cable attached, and it says 5V 2A/5V 1A input and 0.8A output...
CE mark! CHINESE EXCREMENT! Half this China crap is not capable of passing UK safety tests or standards! I didn't buy tackle on the cheap, if came gratis from UK suppliers where buying genuine safe brand batteries! They should be ashamed and held accountable!
Remember when we used to just plug a thing into the wall? Now we gotta plug a thing into the thing we need to plug into the other thing we plug into the wall.
I got a very similar looking charger some time back. I stopped using it because it got suspiciously warm and didn't appear to stop charging at 4.20v. If I still have it and find it I should send it to you.
It looks like it has a similar layout to my charger for my e-cigarette but recently snapped the plastic off and broke the wires I had a charger for one of those e-cigs at called blue it's polarity was reversed from the all the other normal chargers and it's a wee bit more complicated
How would one of these handle a cell that has been deeply discharged? I've seen sophisticated chargers that will refuse to put any juice into a battery if it's voltage is too low. I have a SkyRC MC3000 which is one of the most sophisticated chargers for cylindrical cells, and sometimes I have to parallel a charged battery to "bootstrap" the charge.
I wonder what happens if you insert the battery wrongly? Will it still try to trickle charge it with 50mA? I see nothing in the lth7 datasheet that says the opposite... PS: Charge current should be Ich = 1V/2.2kΩ * 1000 = 455mA, while the trickle current should be 1/10 of Ich, that is ~46mA.
Have you done a video on the cheap, fold-out wall plug ones so I can worry? I was just charging an 18650 in one of those about 1/2 hour ago and it just seemed kind of sketchy to me. Really, Homefire? What great marketing.
Adding "Homefire" batteries to my list of reasons to buy a label printer
I have a couple of them for like 10 years they are very useful
What's the connection between these batteries and a label printer? I think I've lost the point 😅
@@88Timur88Bahmudov88 Take a look at the thumbnail for this video.
Just use a regular printer and self adhesive paper.
Had a good laugh from HOMEFIRE brand "20k" mAh cells, cheers Clive 😄
That made me laugh too
I must be getting behind the times. The highest fake 18650 rating I've seen is 9000 mAh.
10,000mAh of actual charge plus 10,000mAh of actual fire.
“20000mAh” is brand name, not capacity.
@@hanelyp1 also fake
I have the 2x version of this. It's the same circuit twice, for anyone wondering.
That’s a nice obvious way of doing it, better than just putting cells in parallel.
A lithium battery named homefire is hilarious
Looks like a printout from a labelmaker, the actual heatshrink is red. Anyway, the _“-fire”_ brands are indeed getting ridiculous.
Trustfire are the wraps I'm familiar with. Dangerously misrated wraps that probably caused a LOT of damage.
ULTRAFIRE
well, it promises something it could easily deliver!
I have a Chinese spark plug called 'Boil'
First thing I saw as I picked up my tablet was the notification of this video. That reminded me that I had a couple of 18650 cells on charge and I was not certain of their reliability. A quick voltage check suggests one of them is definitely a bit dodgy, I'm glad this video reminded me to take them off charge.
In actual fact, the charger is a modified flip pin charger, pins removed because I didn't want to plug into a death adapter and a flex and UK plug substituted. The open circuit voltage is a reassuring 4.2v and although I couldn't check the transformer itself, everything else seems pretty well constructed so maybe they aren't all dangerous crap. Twin charger with separate control on each circuit.
Much better design than the one I opened up and all I found was ..... a resistor. 🤝
You'll know when the battery is charged by the lithium venting.
@@JasonW. I laughed at that way more than I should. 😄
Hey, at least it *has* a resistor and not just a really thin cable doing the same thing.
@@aprilkolwey4779 Wire? You mean a high tech Tesla cell fuse, right? 😁
"We didn't start the fire, it was always burning, since the world's been turning..."
Brilliant. I have the same charger but in a dual cell version and I started to question the reliability of them. You've put my mind at ease. It seems to be able to also charge the 3.2V LiFe 14500 cells and it knows to stop at 3.65V despite its 4.20V charging output. So more intelligent than I thought. Mine is a 1000mAH output version though. However, that could just be 500mAH per cell since it's a dual cell charger. I think they addressed the LED brightness in the updated versions as now they are plenty bright enough. I have a Green LED for full charged and Red for Charging status.
The exact same circuit is built into my (dead) electric toothbrush.
Where can we get these homefire brand batteries?
I think RapidFire makes em 😂
Fleabay, big rock candy mountain (china).
I searched for homefire on AliExpress and there were a lot of search results.
You could get them at one store, but it burned down
@@contrarian8870 now made in house for faster shipping
1:35 You are a very brave man, grabbing that dubious quality charger in a way that makes contact with one of the conductors.
My guess is that BigClive knows *EXACTLY* what is in that yellow USB power supply between him and mains.
I like these low component-count designs much more than the old mains-powered ones with a dozen components. Less chances for the manufacturer to use substandard parts, on top of lower shock risk.
i Like how you work. your explanation are very deyailed. no silly music. I feel like i am in class. keep up the great works
I was talking to a friend on the phone a couple weeks ago when he got a message: his house was on fire.
He left a cheap 20AH 48V LiPo battery for his boat on a charger, outside. First the boat caught on fire, then the house. Total loss.
Play safe everybody.
You know it's still 2020 when Clive actually recommends something bought from eBay as a good product.
Clive has recommended stuff from Ebay in the past, like head torches, resulting in them selling dozens and dozens more after the video dropped. So that's not _that_ unusual.
Might be a cheap and easy way to integrate swappable Li-ion cell(s) into a project?
The original worklights on my boss's Huawei mini wheel loader are called "Arson".
4:18 - "One moment please.." 🙂
Took a few times of looking up the data sheet, but I now do finally recognize the LTH7 IC silkscreen, since it's in nearly all my cheap self charging electronics.
Datasheet here www.analog.com/media/en/technical-documentation/data-sheets/405442xf.pdf
Considering some of the cheap chargers that've shown up on this channel, I was seriously worried that thing was just going to put the 5 volts from the USB right across the battery, with maybe a token-gesture resistor. I was pleasantly surprised that it's got proper, relatively sensible circuitry inside.
Did you know, Clive, that Argos now sell singular Molicel P26A 18650s in plastic tubes? They’re in the _”fogstick”_ section. Really excellent high-drain cells with 2600mAh capacity and a stated CDR of 25 amps. I wouldn’t give them a load of over 20, though, for heat reasons in a high-drain application, but they’re very respectable cells overall.
Lmao i clicked the video bc the battery said HOMEFIRE LMAOOOO
this chip is actually LTC4054 made by Linear Technology, so it has maximum charging current at about 500mA, and does have thermal limiting.
I like the LED circuit. I will store that configuration in my circuit tool bag.
You should be a Chinese Cheap Product Checker - you find so many cool features to point out (like better position of the capacitor / led resistor value)
Excellent tear down and explaining it's components innards .
Nice. I recently bought a 4 cell USB powered charger. Each battery charged independently. Springed contacts so will do 18650 & smaller.
It's fairly ironic that looking as something qualified as "a textbook design... actually pretty good" becomes a welcome surprise when looking at low-cost end-consumer electronics.
I have a few similar to this only they plug directly into a wall socket via a 2 prong plug. I don't know weather it was the type of battery I used or what but one of them blew up when I switched it on to charge, after that I never used them again and bought a proper li-ion charger.
Love the thumbnail - “keep the homefires burning”?
One of ours cats was absolutely fascinated with the pcb study section, maybe we can add your channel to his list of UA-cam birdie TV for cats 🐈
I apparently have a huge cat following.
The application note states the Earth Pad needs to be a large copper area for best thermal performance. Also the pin that is being used to switch the LEDs is limited to 10mA. Also note this pin is in fact a tri-state pin indicating 3 different states of the charging circuit. See the application note for details.
You're braver than I. I wanted to look into replacing li-ion cells myself, but after one that I removed hissed at me I'm leaving it to the pros. Unfortunately even places like Batteries + won't touch them.
Mine used to do that too but now i have learned to charge and discharge them at no more than C/10. Had no problems at all since then - even charge them on my bench supply (set for 4.2v per cell).
Mr. Clive you should totally make more trash kitchen videos. Love your videos btw
Not sure I like the charging current being passed through the spring, be interesting to see how much voltage that drops under full charging current.
Yeah, thinking the same here.
I bought a couple of similar chargers and I had to take them apart and bypass the spring with a wire. Otherwise the spring has too much resistance and results in the charging cut off at less than 4.1v. After the bypass the happily charges up to 4.17v and I've been using them for a couple of months without issue.
I've got a similar looking one that plus into the mains (Type A). It has the helpful label on the front that reads "Intelligence can be positive and negat I've charge quick charge, Safe and reliable". It lets me know at a glance it wasn't manufactured anywhere in the western world. I haven't taken it to bits yet, but I probably should before I do something silly like plug it into the wall.
When you take a picture to show to us is it on photo paper because it seems pretty clear
Those are equal parts clever and infuriating in their mechanical design. I'm not quite sure why I have such an aversion to that sliding contact, but it is very clever.
Because you've had the infuriating experience of trapping your fingers in them in a past life, maybe?
@@penfold7800 I think it's more that they often make very poor contact.
@@penfold7800 instructions unclear, dick stuck in battery charger...
Great video Clive.
They could put 2 or 3 2.2k resistors in parallel and still keep the same pick and place BOM,,, but that would cost a micro cent more!
With only 2 resistors per unit and only six different component types (if I counted right), adding a seventh reel is probably cheaper than adding a third resistor.
I was expecting one of those blue pcb battery charger that you can buy from electronic sellers online
they're commonly using the tp4056 chip which IMHO is somewhat better because of up to 1A charge current possible, so I guess this one must be cheaper. On the other hand here you get the 18650 holder as well, not just the PCB, so in terms of DIY this charger is probably a better purchase.
Waiting for the "Uncontrolled Fire" brand cells.
I see your "Uncontrolled Fire" and throw down a "Firestorm".
Don't make me use my "Hiroshima"!
Dreamfire.
The battery is from the future....😱
I ripped out all the electronics out of the mains version of this charger and put in a TP4056 charging board. The original electronics is dangerous and would overcharge the battery.
Nice catch, great save. 8)
@@wojtek-33 the mains powered version I had didn't have any chip. That's tje one I put in it.
The PCB seems to be a cheap one, look the track shapes, they are not straight and the PCB border seems to be done manually.
A charger with a strain gage ! That seems like rather bold strategy. ;)
Should take a look at an xtar vc4 or vc4s charger does NiMH, NiCd and Lithium ion batteries at the same time
Probably costs more than 3 quid, though.
@@RedwoodRhiadra £16 but is a lot more useful. The vc4 is the normal charger, the v4s does a full discharge charge cycle with capacity testing along with being just a charger
I'd like to see the difference between one of these and say the LiitoKala or Nitecore chargers.
Nice video, thank you! Will the charger shut off on its own?
Yes.
Could this type of arrangement be used to power an emergency light?
Charger is rated 4.2v 400mAh. Heat is the enemy.
Clive, video idea: how charging is handled in devices that are in use. I've been trying to figure out how that's done properly and having a devil of a time finding good resources.
The simplest method that comes to mind which isn't garbage, the charger supplies constant current to the battery terminals until a max voltage is reached, then shuts down until the voltage drops to a restart level. Actual charge rate is reduced by the device load. Depending on device current draw, a modest time delay between charge shutdown and restart may need to be enforced.
if the current setting resistor values give the same charging currents as in the 8 pin version of the chip, 1.2k is what you often find in power banks, which gives a charge current of 1A. 1.5k would give you about 750mA. 1k would give 1.2A, which is probably a bit too high.
the formula is I = 1/R x 1200
They're called HOMEFIRE because they set your home on fire.
I've used those to charge CR123A's with a stack of nickels wedged in to reach the charger contacts. Should I not have done that?
If the cells were OK with 500mA charge current it's not an issue. I've done the same in the past.
I'd have used pre-1982 copper (bronze) pennies. Better conductivity. However, I've even used nickel plated neodymium magnets to extend the ends of my 18650's, with no problems.
I have a very similar charger that came with a flashlight to charge the 26650 battery and it seems to work just fine for the two different batteries I charge with it and I've been using it over 2 years with no issues. It will typically charge a battery up in about 2-2.5 hours depending on how much I drain them. I just plug it in an old USB phone charger and won't plug it into a computer.
I have decided I really like the 3 AAA flashlights because in a pinch you can cut any usb lead and put positive to one end of the pack negative to the other and you have a crappy nimh charger.
That's not regulated. Unless you're talking about powering a mobile phone (where its own power input and battery would regulate power) it wouldn't work very well. You could trim one of the led outputs and use that to charge, but it would take a long time!
Time for a project Clive 😊 been waiting for one for a while now...
It's unfathomably ironic that fake Chinese batteries always has "fire" in the name.
How about a quick one where you change that resistor and make it brighter? Actually, I am wondering if that will have an impact on the chip itself.
Just solder another resistor, of the same value, onto the top of the original resistor. It will rob the charge current of a few mA's.
Always awesome vids love a hug off him 😉
2:22
You're measuring 460mA between the 5V USB charger and the battery charger.
To measure the charge rate you should be measuring between the charger and the battery.
Would make no significant difference, as the charge chip uses a series pass element and its own current consumption is insignificant compared to the current going to the cell.
True, but you can work it out to be 540mA at 4.2 volts, so it's most likely going to come in at half an amp or so for practical purposes. That's about where you want to be for an 18650.
@@Chris_the_Muso - there is no inductor, so how do you get 540mA? With a series pass element regulator, the current input equals the combination of the output current plus the current used by the regulator itself (which is likely to much less than 15mA). The charging current may be higher if the input voltage is nearer 5V and/or the cell has a lower state of charge.
@@Mark1024MAK He measured before taking it apart. I'm just saying it's not the correct way to measure charge current.
@@Mark1024MAK Ohms law, with a nod to the power law. Actual charge current will be higher than the draw current since it's essentially a CV buck converter, whether or not there's any kind of inductor in the package. There will be some losses but it's not significant, not for a $5 charger anyway. S'not an Apollo mission. That's why Clive said "about 500 mA".
I ordered a few of those the other day, gonna gut it and use it as an adapter for my proper charger that sadly can't fit protected cells.
are some of the posters time travelers ... some posts say they were posted 2 weeks ago .. video only went up 10 mins ago
It still amazes me that people who watch YT vids have no idea what Patreon is...
He's on Patreon, so I'd guess one of the benefits to patreon supporters will be access to videos early. When it says the video went up 10 minutes ago that means that's when it was made fully public, it could have been on youtube for years, only accessible to those who have a direct link to it.
Maybe that's when Thier post bot was initialised lol. (or for some reason YT posted the time signature from the poster's source, not from its own server clock)
BigClive patreons get an early access yes.
@@bills6093 It's probably a good sign if they don't know. As in maybe they spend most of their life in the real world and not UA-cam
I wonder if the LED resister is sized to protect the chip from over current.
This looks like the one I got "free" with a electric precision screwdriver, it charged the battery once and then maybe coincidence but the screwdriver stopped working seconds after I put the charged battery in and didn't work with any batteries.
Probably coincidence. The screwdriver was probably worse quality than the charger. You could most likely pull it apart and fix it, but the real trick with those small screwdrivers is getting all the cogs back in the right places. The electronics are probably quite simple however.
Had a "homefire" branded 18650 make a pretty impressive bang recently while charging. Shot hot black debris all over the carpet and filled the room with smoke that would be useful for riot dispersal... Saying "Never again." would be redundant.
Did you over charge it.
@@simontay4851 Most likely scenario. May have also missed a ding in the cell. The charger is still fine. Shuts off at 3.8ish The cell is pretty far beyond reconstruction. The whole thing was less than confidence inspiring... I dislike mysteries
Ok you NEED to get some merch made with a image of a HomeFire battery on it..
The chips are very cheap. JLC can fit an equivalent (4054) on a board for about $0.025 each (plus $3.00 to load the tape)
I was having a hard time finding the part with the homefire battery because of the comments but then I realized it was the thumbnail..
I like how simple this is. What is the common failure mode of this chip though? Could it potentially overcharge the battery? I try to never leave lithium batteries unattended while charging, however i do forget some times and leave my flashlight battery plugged in at night. I do try to keep it clear of anything combustible, just incase. I also use protected cells. But redundancy is never a bad thing when it comes to safety.
Redundancy is always good. I'm not sure what the failure mode of this chip is. Going short circuit is possible. That's where protected cells have an advantage.
@@bigclivedotcom Interestingly this prompted me to take a look inside my 2 instances of this charger. They do have Red and Green, Charge and Charged led's but also an A1sHB p-chan Mosfet on the output of the LTH7 charge controller, Ground and Positive O/P.....
I'm now getting wine ads on Clive's videos. Sadly with a lack of carbonation.
Hi bigclive i would have been interesting seeing you improve the LED as you say if can be done. Because i oneday want to start to building some things so i learn from you myself.
Surprised that they go to the trouble of using 4 screws to hold the back on, when a built-in clip or clips would suffice.
I think that the Homefire is seriously funny, but the 20000 mAh really takes the prize!! Thanks for the laugh, Clive.
Four screws are easy for a Pick and Place automated assembly machine. 👍👍
@@acmefixer1 But a pick and place machine is far more expensive than a village slave labor.
So, erm, am I right in saying that because there's no diode on the charging output side, it doesn't have any safety against putting the cell in the wrong way round? (Potential for Lithium meltdown)
datasheet says "No MOSFET, sense resistor or blocking diode required"
Guess thats all built in...
Likely built into the chip.
Ah, this is quite receptive, able to accept a wide variety of lengths and diameters. Beauty is in the mind of the beholder! Tee hee;)
If you can find them cheap enough they would be good for Home Brew cell charger dischargers using the spring cell contacts / terminals. Say a dozen or more.
Go on then Clive... Change it for a 1k and get the heat measuring kit out... Is it a worthy replacement or will it just go pop?
0:36 I thought quad comparators were literally cheap as chips? They could have easily squeezed one in there with a few LEDs.
Nah, need space for comparator, need more resistor dividers for voltage references... That's definitely too much work for someone that puts 2.2k resistor on LEDs to save on BOM and Pick and Place... 😁
Edit: probably would also need a double layer pcb or thinner traces to go under resistors, you know how expensive that is??? 🤣
As always, very informative and that, but I was kinda hoping it would catch fire as soon as it was connected 😂
I just got one via Amazon to review that's nearly identical in appearance, altho it has a permanent USB A cable attached, and it says 5V 2A/5V 1A input and 0.8A output...
Thanks for the overview - though I'd rather stick to my Nitecore d2, Nitecore i4, XTAR VC4 and Turnigy Accucel 6. :)
Would live to see this modded for brighter LEDs and 1A charge current.
I've had a few of those shit chargers, they've all melted near the charge indicator!
So... no temperature sensing then?
Depends entirely on the charging IC, it’s likely they put counterfeit ones in there
CE mark! CHINESE EXCREMENT!
Half this China crap is not capable of passing UK safety tests or standards!
I didn't buy tackle on the cheap, if came gratis from UK suppliers where buying genuine safe brand batteries! They should be ashamed and held accountable!
Remember when we used to just plug a thing into the wall? Now we gotta plug a thing into the thing we need to plug into the other thing we plug into the wall.
I got a very similar looking charger some time back. I stopped using it because it got suspiciously warm and didn't appear to stop charging at 4.20v. If I still have it and find it I should send it to you.
Same, mine actually started to melt!
It looks like it has a similar layout to my charger for my e-cigarette but recently snapped the plastic off and broke the wires I had a charger for one of those e-cigs at called blue it's polarity was reversed from the all the other normal chargers and it's a wee bit more complicated
you should have a box of those little USB to mini cables around. Generally reliable or sometimes dodgy? I use OEM if possible but sometimes..
I've heard that homefire cell is very good for cold places, like, you know Isle of man in the winter
- HOMEFIRE? Shut up and take my money!!! XD
How would one of these handle a cell that has been deeply discharged? I've seen sophisticated chargers that will refuse to put any juice into a battery if it's voltage is too low. I have a SkyRC MC3000 which is one of the most sophisticated chargers for cylindrical cells, and sometimes I have to parallel a charged battery to "bootstrap" the charge.
Nice. At least looking from phone's screen it looks like slider has been stolen from generic office stapler 🙂👍
Oh my! Is the TC4056A already outdated?
How do you do the exploded view?
my battery is called ultrafire.................sounds even more dangerous!
I wonder what happens if you insert the battery wrongly?
Will it still try to trickle charge it with 50mA? I see nothing in the lth7 datasheet that says the opposite...
PS: Charge current should be Ich = 1V/2.2kΩ * 1000 = 455mA, while the trickle current should be 1/10 of Ich, that is ~46mA.
not gonna lie, clicked for homefire
Have you done a video on the cheap, fold-out wall plug ones so I can worry? I was just charging an 18650 in one of those about 1/2 hour ago and it just seemed kind of sketchy to me. Really, Homefire? What great marketing.
What features does the LTH7 provide? You mentioned thermal protection of the chip itself.
Protections -- over-voltage? under-voltage? over-curernt?
See www.analog.com/media/en/technical-documentation/data-sheets/405442xf.pdf
"Keep the homefires burning..."