Entertainment and education in the one package. Clive would make an excellent Technical College / University Lecturer (he beats many of my past lecturers whose delivery was "less than engaging"!)
LiFePO4 delivers a much higher number of charge-discharge cycles while also degrading the least of any lithium chemistry while they're held at full charge. They're the only lithium chemistry I'll consider for backup power because of this and their immunity from need for an explosion containment pie tin around installations.
Assuming you can get them used, NiFe batteries are pretty much the best possible solution for backup power. Immune to overcharging, immune to direct short (both just boil off the electrolyte. Refill with water and you're golden), and with a cycle life far beyond any other technology. They're heavy as frig and very expensive when new, bu those are the only real cons.
NiFe is interesting for some applications but they have low discharge current, high self-discharge, and you can only get out slightly less than 1/2 of the energy that you put in. Edison was producing NiFe batteries for electric cars over 100 years ago because they were the best technology available for a long time for such uses.
5 years ago I picked up a set of 8 solar powered lawn lights (the kind on a small post you stick in the ground). They're powered by one 14430 LiFePO4 each. They've been out there through Upstate NY winters, summers, 365 days a year. 6 of them them will still, given a fully sunny day, burn brightly for at least 8 hours in the summer, around 4 hours in the winter. 2 have significantly weakened. Call me a LiFePO4 phan.
I've actually been building a portable solar system with a 65x55cm 50W panel and a pelican case housing a controller, a 12Ah LiFePO4 12V battery and water proof connectors so it can withstand rain. I'm glad that I went with LiFePO4 instead of Li-ion
Thank you for the great videos. This is my favorite channel and has increased my knowledge so I’m not just replacing and re soldering broken components but actually understanding what the components do and why they broke. Thank you so much for taking the time to do this.
@@johnpossum556 mine in the winter has seen more voltage sag under load and slower recovery. Capacity however has remained similar enough to not really notice.
I have an e-bike originally designed to run on 24v of SLA batteries, and it's been retrofitted with a stack of two LiFePO4 (i like to pronounce them 'life po four') which have 4 cells in series each, which for all intents and purposes makes a great drop-in replacement for a 12v lead acid battery.
I really enjoy your videos. I am a novice with electronics but have learnt a bit watching your videos. Also found your recent video on Alzheimers disease and caring for your mother very informative. Keep up your good work.
Rich rebuilds used a defective charger on the Tesla 18650 pack which made it go above 4.2 volts per cell. Then bang. It was a great example of how important good electronics are for managing a lithium ion pack.
_"I don't think it was defective. Just lacking the battery management."_ When you've got about a thousand 18650s hooked up to it near people or property I think making or arguing over 'distinctions' like this is somewhat missing the point no?
@@bigclivedotcom He said in a followup video that the charger went to high on the voltage. I just used the terminology defective to simplify things and give him the benefit of the doubt that he is not the one that manually chose the incorrect voltage. When you remove a battery block from a Tesla model S my understanding is there is no over voltage battery management as part of the pack so you have to included it your self in your design.
no cell protection on charging is asking for a fire, this one wont be the last and its def not the first, seen people lose their homes and pets charging bikes etc, still to this day no one has built what i would call a proper cell balancing protective charger, bottom balancing has always made more resistant packs, but you need a charger that will bottom balance the cells and then bulk charge stopping when any cell hits 4.2 (4.1), thats how i charge my packs, but have to do it manually in 2 stages as i have a 'normal' charger that wont do both in sequence
For large diy systems the batrium longmon’s system seem to be a good option but for medium to small DIY projects I have not found a product I trust. So when I converted my lead acid electric lawnmower to 18650’s I just decided to do everything manually each time I charge. I use a simple power supply set to the voltage I want for the whole pack and check each cell voltage my self to initiate cell balancing manually. Building the pack with individual cell fuses is also super important for DIY, that has saved me once when a cell reversed and tried to drain the whole pack.
one thing everyone in the comments seems to be missing is that, while LiFePO4 is less energy dense than other chemistries, it has greater *power* density. the electricity within can be discharged faster than other kinds of lithium ion batteries.
Well it can be discharged faster without catching fire, but at even 1C you will get a maximum of 60% back from the battery. They are safer, but give up performance.
Howling Wolven And where can you buy them? Last time I checked, nothing with graphene made it to the market yet, at least at reasonable prices (except maybe graphene supercapacitors, but that’s not a viable alternative to batteries).
@@googleuser859 it's almost as if writing quotes from a video under the video without any commentary is pretty pointless... oh, and in no way, shape or form original
@@NiHaoMike64 For us casuals, just coincidence. For any hardcore scientist or quantum physycist or chemist, this warrants an entirely new front of investigation! Or it's just rounded to numbers people can easily memorize.
Excellent video. I like to tinker with things myself and learning about batteries has helped me. I have two solar street lights. Two things I look for is: 1. How much does the solar panel actually output 2. What type of batteries are in it and are they actually rated for the capacity spec Well I found that the panel indeed outputs what the specs stated on the listing. But with the batteries this is where they go cheap to save money. Usually some used grade b cells that are 40-70% rated capacity. Which is why most people find that the solar light stays on for half or less than what stated. Most cases there is more room in the casing to upgrade the battery capacity.
So, two things, one for Clive, one for the comments. Clive, one thing about the two FETs, you're right about the diode blocking, but that's only part of it. The 'OC' is charge FET, and the 'OD' is discharge. That's how the chip is able to cut current flow when it exceeds a threshold. As for the LiFePo4, they're 'better' for some applications. One nice characteristic is that you can usually charge them pretty aggressively and they'll take it. I've seen some that will allow you to charge as hard as you discharge. That's great for regenerative braking or hybrids. I wish they were more popular so the price would go down.
Since you mentioned practicality of solar Christmas lights.. Yay Clive!! I have played with a standard sized garden "solar bank", panel about 95mmX80mm with lithium Ion, as well as many 50x50 with NiMh. The NiMh units all had 600 or 800mAh and "high" operating current of 35 to 50mA and drained the cell whether or not connected to a string of lights. My load was the magnet wired seed/fairy lights that required only about 15mA but unfortunately could not span even one cloudy summer day. One unit that is NLA had 2mA operating I. I imagine that's either about protection from overcharge or poor design. The lithium bank had 8mA drain, auto-dimming, a cheapo 1200mAh cell, and performed well even during the winter solstice near Toronto, Canada. Not super bright, but indeed super pretty. Partially thanks to you I have custom 12/24" pitch fairy lights... Beware of the wasteoids!!
I would venture to say that Rich's battery accident had more to do with his battery pack not having a BMS and possible overcharging rather than the types of cells he had. But nevertheless great video once again!
both of my work vans are entirely LifePo4 including the starter battery. Both have auxillary battery systems of 160AH and 800AH respectively and lifepo4 is the only way to go. I can draw hundreds of amps with little to no voltage drop all the way to 80% discharge.
@@UniCrafter The 800AH bank runs lighting, inverter, kettle , microwave and bits. I often work on site for days at a time and charge a cherry picker battery from it too, that draws ~60A alone.
@@amojak ah right, I watch a russian youtube channel and the owner owns a hummer with 1 or 2 banks of 1500AH of lithium, and runs a 40,000w sound system off it lmao
@@UniCrafter i can believe it. I do actually have four 1000AH cells here , originally bought for a van but they are too big to fit. hence i used nearly new leccy car cells instead.
Another point of having two MOSFETs, even if there wasn't the diode issue, is that it allows it to independently block charging vs discharging. When the battery is at its max voltage, you want to be able to prevent further _charging,_ but you don't want to prevent _discharging_ (which would just make the battery useless), and likewise when it's too low, you want to prevent further discharging but don't want to prevent somebody being able to charge it back up to make it useful again...
After watching Rich's pyrotechnic display I think I'd go for these lithium iron phosphate cells for my DIY powerwall. I've got a lead-acid server room UPS and these batteries stack up nicely to 12V.
8:40 "feels like defusing a bomb" I was thinking just this morning that I'd love to see a Big Clive video about collapsing circuits and other Hollywood bomb tropes. With fireworks. And cats.
Appreciate the video. Keeping the technical withdrawal DT's away over this festive season :) Hope you had a great Christmas New Year. Love your video's Clive.
I'm presently using these grey Lifepo4 cells in a self built 10KwH battery bank charging off of 2Kw of solar panels fixed to the roof of my truck. I control the charge/discharge Voltage via my solar charger/inverter & balance them with BMS boards. They work very well: many times more efficient than lead acid & very long life compared to Lithium ion. With the right charge/discharge profile they may well last a lifetime with just a little power loss that can be offset by adding more batteries in the future.
"That's just the peril of solar panels, they don't put out much power when you need it the most." is a very accurate summary of my experience with them too. Although I guess maybe if you're in a hot climate and plan to run your air conditioning on a battery buffer + solar panel its output trends will meet your demands better. Technically solar panels get less efficient with heat, but when allowing for some ventilation around the panels the extra sunlight to convert into electricity is almost guaranteed to compensate generously for that "efficiency problem".
A few years ago people would disassemble DeWalt battery packs to get their hands on the A123 cells, which AFAIK use this technology. Major advantage: you can charge and discharge them at ridiculous rates.
The two mosfets used with cell protection chips like that actually operate independently to block in one direction for over-charge and the other direction for over-discharge.
This chemistry is used in cheap solar street lights because the voltage matches that of white leds , often they feed the leds direct with no other circuitry , the flat voltage with discharging keeps light output fairly constant.
You just need to come hang out in Southern California for the winter. We've got plenty of sun for your solar Xmass lights. It's just a pain to string them on palm trees ;) IIRC Andreas Spies did a bunch of tests with different battery types including the LiFePO4 cells about a year ago. -Jake
I use them in the AA form, in pairs with dummy batteries, in high power flashgun units (Sony HVL-F60M, Godox TT685s) . The refresh rate for a 1/1 discharge is about 1", which is much less time than when using NI-MH (or seldom Alkaline). The downsides are the relative low energy density, the (sorta) special charger needed and the inability of the flashguns to cope with overheating... the last I suppose is probably due to the flash designers expecting a longer recycle time from 'common' batteries :-) I was very pleased to find them, albeit a bit pricier, in a big french retailer currently operating in Greece, in the spares section of solar garden lights!
LFP batteries from Battle Born/Dragonfly and a few imports are being used in RVs. The BB10012 is a 100Ah 12V pack in a car battery form factor that replaces the deep cycle coach/house batteries. LFP in a 4-S configuration yields a more compatible (than Li-Ion/LiPo) 12.8V nominal voltage and a range of 14.4-10V (BMS limited) which works well enough with lead acid charging systems. More stable and safer than Li-Ion with a 10 year warranty. LFPs are fussy about temperature and go off-line below freezing (25 degF for charge circuit, lower for discharge) so some owners move them inside the coach since there's no hydrogen or corrosive gasses venting out. The cost is high initially but lower than LA over their lifespan. Charging efficiency, minimal self-discharge, usable capacity, and light weight crush lead acid performance.
I got a 20Ah 36v LIFEPO4 batttery in my ebike, using it with a GNG electric motor kit. I put it together myself, mid engine with the belt drive, great in hills :) The LIFEPO4 batteries shall be good and i cannot complain yet, i has had it for like 3 years. I put a saddle pack over it so it looks nice under it on the rack. Tesla use the 18650 batteries i has read somewhere.
That other video reminded me of a fire at the local fireworks factory. I was having flashbacks to the great war...and i wasn't even alive at that time. Impressive, very impressive.
I started buying only LiFePo, because in Arizona and West Texas, the denser/standard lithium battery packs for jump starting a car or charging a phone will expand. Never had one explode, but it's not worth the risk. I even used a permanent car battery size for a few years, and it had no trouble in freezing 🥶 or burning 🥵 temps.
I think it's touchingly patriotic of Glaswegian officials to have earnest meetings and a few experiments about the possibility that Glasgow in December might be the perfect place to utilise solar power. Us Sassenachs that have visited Glasgow in December probably wouldn't have wasted our time in the meetings - but love of country is a powerful and mostly admirable thing.
For EV's Tesla is not using LiFePO4 chemistry in its battery cells, but NCA. For model S, the cell type is the 18650 (like the purple one you hold). For model 3, it is also NCA chemistry (LiNiCoAlO2), but in the 2170 (21700) cell model.
Strange how words bring back memories of our youth, for example you said slit, and the old tongue twister "I slit a sheet; a sheet I slit; and on the slitted sheet I sit!" rushes through my mind. Don't know if that one made it to your side of the pond or not.
Another advantage is the voltage. 90% of the capacity they stay between 3.2 and 3.4V tange... so you can power 3.3V chips (Arduino projects..) directly. At the same time it’s a disadvantage as it is impossible to guess their charge level by voltage (works somewhat for lunch-ion) as the voltage sits so close to 3.3V between 30% and 95% of capacity. Military likes to use such batteries due to their tolerance in case of improper handling. Some people here say they are expensive. Can’t confirm that. I’d rather say they are cheap. Many types are tested for 5000x and more cycles, taking this into account they are easily 10x cheaper in kW/h
Hi Clive, I'm confused. I think you are saying at 1:44 that lifepo4 batteries are used in electric cars because they are safer, but they can catch fire as in the rich rebuilds video. But are tesla batteries Lifepo4 ? I thought they use 18650 batteries like the purple one you are holding, not the grey one. And thanks for testing all sorts of electronics, love your video's!
YES at last a video about Lifepo ! Do you know the LITO batteries ? Lithium Titanate. It's a very cool battery and i think it would be fun to test and open. And you could do a series on batteries, because there are so many different kind, maybe just the interesting ones.
4 of these make great replacement for 12 batteries in kids toys and UPS. UPS batteries often kill them selves when used. These cost a fortune but well worth it you have multiple power failures and let them run to zero.
This streetlight will work fine closer to equator. Because of the lack of distinct winter season with many dark hours. Else you may add low voltage from mains via a "winterswitch".
It is amazing how much energy these modern batteries can hold, I assembled a 3S-3P 18650 pack this morning and just held it in my hands marvelling at the fact it has about the same, if not more, energy in it than one of my 12v SLA batteries, but also the fact that if the SHTF and the things went boom, they'd be a lot more lethal than said SLAs... :S
So in the first video you measured the battery is that how they sell them by size and capacity. Last night I did a quick search on lifepo4 on amazon they seemed 18850 was popular. It was late I didn't watch your quality video til this morning. Cheers from coldass, kansas.
I had a funny Big Clive moment today (Jan 4) I wanted to share... The blower motor resistor pack died on my car this morning, and I was stuck with only the Hurricane setting for my heater. To add insult to injury, the servo motor that opens the various air doors has been bad for a while, leaving me with only the dash vents, but that wasn't an issue until I was stuck with the Hurricane-or-Off option. Down to the auto parts box store, plug the new resistor pack into the wiring harness and leave it dangling until I get home and install it properly (I've done it with the old coiled resistor type, so I figured this would be OK)... I had all fan speeds for about 45 seconds, when the new resistor pack failed. I look down at it and realized there is a thermal disconnect, a copper-ish tab soldered to another terminal so it fails open when overheated. My Big Clive Moment? I look down, and say (with a very poor accent) "Not to worry, I'll just reflow the sahl-der when I get home." And I did just that, with my 1970s unfused Weller iron. And my fan works as it should, now that I installed the resistor pack deep within the bowels of the modern car dashboard where it can be cooled by the airflow as it was designed. :-)
we use LiFePo4 cells as a 12v starter battery in aircraft. partly for low temp performance, but mostly because they are bulletproof. we shot a nail through one and it just sat there and took it. still it has to be in an aluminium bunker because boeing cocked it up by using LiPo's without adequate protection and without armour in the dreamliner.
A123 systems made a nice 26650 cell, 2500mah and could do 60c discharge which is great for RC cars and even planes where you don't need long run times, they allowed extremely fast charge too for the time, I used them for years and still have the packs I made and are still working perfectly. Lipo cells are much preferred for power density though but they don't last very many cycles in comparison.
I've been playing around with some solar charging of batteries, mostly using lead/acid batteries that I already have. One of the reasons is faking more daylight in my greenhouse (which is why I started making my own version of your RGB LED controller!) Another thing is a solar light for my front gate, walkway and front porch.
For your use, I would suggest spending a bit extra on deep cell gel batteries! Not only will they last much longer, they are designed for constant drain/recharge use. They are more expensive no doubt, BUT in the long run you will buy less of them over time.
Martel DuVigneaud plants grow best with red and blue light. Witch to us is a pinkish purple. They will grow with red and blue. But best with the combo. The blue UV LED's not true, complete UV, but dip into the wavelength of uv. With a red led that also peaks in to the infrared spectrum. Would likely be closest to what the sun provides. Giving only what the plants needs. Not wasting power on other wavelenths of light. Amazon sells the led lights with red and blue for plants. I'm planning a small green house. And plan to use about 10 watts of red/blue LED's per plant. With about 300w solar to start with. And 400 ah in battery. Along with a pwm dimmer. Maybe one for each colour. Allowing to adjust colour and brightness. Sorry for rambling!!!!
@@Malakie Yeppers! I'm experimenting/learning just using old deep cycle SLA batteries that I pulled from and replaced in UPSs where the only other reasonable option is to dispose of them (already significantly reduced capacity.) I'll get new batteries when I'm a little more sure of what I need and what I'm doing. ;)
@@jamest.5001 Yes! That's my intent! I plan on alternating strips of the red/blue grow LED strips and white (maybe 3:1) so if I need I can also turn on white light for visibility for me at night. I'm also planning on assembling a passive thermal heat system: a tank of water in the greenhouse with an out-feed pipe at the bottom running outside to the bottom of a black poly-pipe that snakes side-to-side up an incline and feeds back into the top of the water tank. Y'know, just to give extra heat at night. :D Total capacity of the solar panels, batteries and LEDs plus the thermal system are all still things I'm experimenting with! :D
Martel DuVigneaud that sounds awesome. I'm thinking of a similar , supplemental heating for my off grid house. I have solar power, and a generator. With 4 t105 style golfcart batteries, and 4 huge L-16 leadacid. And 1400cell liion battery bank. That I use separately. Mostly use the lead acid for backup, and use the middle of the liion. So I expect about 40-50% capacity in 15-20 years. I cycle them from 3.1-4v per cell. And in a emergency Can parallel banks when voltage is equal. Or use the generator. I hope to get a tiny hydro electric generator going. And maybe a wind turbine. If I can get a constant 500 watts it would help alot. I'm trying for 1200+ watts on each. There is weeks without sun here. Sorry for all the rambling!!
Damn bigclive, how do you keep reading my mind? First a few days ago I was thinking of asking how you test battery packs and you post a video, and now 5 minutes ago I was literally just looking at an ad that has a whole bunch of these batteries, but much larger. GET OUT OF MY MIND!
@@bigclivedotcom indeed. You could see the initial swelling as an immediate reason to change them out before they get to dangerous levels which is a good thing but in the end both kinds are rather sensitive if you go beyond their specifications in any way
I use 3x26650 LiFePO4 in a power pack for my instrument effects pedals. The pedals handle the 10.8v immediately after charging fine and at the pack stays at around 9.0-9.9v for a long time. Much safer for charging/handling, and less stressful on the 9v pedals' circuitry compared to the alternative higher voltage Li-ion alternatives.
The problem with solar is it doesn't work in the dark. However if you use thin film solar panels you can get probably close to full power in un-idealistic situations. ie. bad angle to the sun, overcast, partial shading etc. Problem is they cost a little more and are larger in size, they have a shorter lifespan and are less friendly to the environment but they should work in Isle of Man or any other overcast area. After that obviously you just size for the application depending on how many daylight hours you have.
Clive you really should keep a bucket of sand nearby in case of fire. Maybe a plan to drop the battery in one bucket and pour sand on it from the other.
That is some quality stuff. Great lessons learned. So is this circuit diagram a smaller version of BMS ? I mean, can I use many of these small circuits in a battery pack instead of a BMS ? I am a Ralfy subscriber for years and I learned about you through him :) keep up bros
Hey Clive, are you sure Tesla packs are LiFePO4? As far as some articles describe, they are using LiNiCoAlO2 chemistry in the new 21700 cells. Older packs used regular 18650 cells (with minor tweaks from Panasonic but still regular Li-ion chemistry).
You might like to get a ceramic knife or any other non conductive blade material you like. Sometimes you can get Soviet scalpels on ebay which are equipped with sapphire blades.
Tesla uses Nickel80Cobalt15Alu5 batteries (plus minus something; The more Cobalt, the more power they have, but it's getting complicated here), which is why they burn so well. Also, they charge and discharge them with a lot of power, you can't do that with your standard lithium cell. We're talking 2C or more here (which is, btw, quite dangerous).
Tesla uses NCA Li-Ion batteries, not LiFePO4. They aren't used much for plug in EVs as the specific energy density is lower resulting is massive packs.
Well, I would sacrifice the energy density for a car that doesnt need its most expensive component replaced every few years and doesnt occasionally explode.
@@Chuckiele In any proper EV, the batteries are heated and cooled to keep them at the optimal temperature for long life. So they don't die nearly as quickly as they do in things like phones and laptops.
Besides the unwillingness to burst into flames, Their higher number of charge cycles is only on paper better than Li-ion. If you charge a Li-ion cell with a voltage range comparable to LiFePo4, it gets the same number of cycles, so energy density, and cycle life is very similar in all but the most demanding applications, Cost Wise LiFePo4 have an advantage.
The lower nominal voltage of 3.2v also means the W/h rating will be lower for the same mah capacity. Mobile phone batteries are actually using chemistry now that nominal voltages are rated as high as 3.9v with a full charge voltage of 4.4v
@bigclivedotcom Clive, stop it! Enough! I'm trying to get work done but you keep posting excellent videos that I have to watch. You're killing my productivity. ... Oh, to hell with it. Keep 'em coming.
given how solar isn't going to keep ya warm in the winter anyway, can you look into thermo-electric generators? You'll get to talk about Seebeck effect & how your stove can keep the batteries charged
Clive, I was wondering if you could get hold of the advent calendar helicopter that Stuart Ashen and Nerdcubed(Dan) Built over Christmas as it's not working? It would be interesting if you could take a look at it =)
Big Bob is one of the smartest guys I seen but Tesla does not use lifeo4 battery’s they use the regular Lithium ion cells , and that is why in that video he has link to it started to explode but Tesla is the only company that has made the Regular lithium ion cells less dangerous than any other company due to the battery management system and the way they place them
I also think that electric cars, especially Teslas, are using Lithium-Polymer based cells for their battery packs, because that's the only way how they can get something like 100kWh into one car. Maybe car manufacturers like VW, which used to build only internal combustion engines, playing it safe on electric vehicles until it's almost too late, and now offer electric cars with ridiculously low ranges per battery charge, use LiFePO4-batteries for their cars.
The most significant difficulty with LiFePo4 is cell balancing. Once a cell is charge it basically will float up in volts and not pass any more current through it. This means if one cell charges faster than the rest it will prevent the rest charging fully. The other issue is not letting the cell discharge below a set voltage as it will damage the cell, so you need protection per cell for charge and discharge as well as balancing (a load switched across a charged cell so the rest of the cells continue to charge). You can match cells to minimise this as an issue and suppliers like www.ev-power.eu sell such 12V monoblocs and i use them here.
It's even worse with Li-Ion cells. Without BMS, the weakest cell in series will never reach full charge, an the strongest cell will overcharge, causing degradation or fire. A Battery Management System is an absolute must for lithium battery packs. Even if you start with matched cells, they will become unbalanced. With LiFePO4 cells this is inconvenient. With Li-Ion cells it is dangerous.
Hi Clive, What's the temperature stability like? Li-Ion are terrible when they get cold, is the LiFePO any better (with this being an external device)? BTW, is that 18650 you're waving about really 3100mAh? I tend to look at anything over 2600mAh with suspicion unless it's come direct from a manufacturer.
These things last ... forever. I've put a LiFePO4 pack of 48Volts (52 actually) with an external BMS on my electric scooter... back in 2007. Still charges today like a champ ! Somebody show me a normal Li-Ion battery of a phone that lasts reliably more than 5 years...
I wonder if the "true switch" back-to-back silicon MOSFETs are necessary now that GaN Mosfets without body diodes are becoming more commercially accessible now. Silicon is obviously cost superior, but is that the only reason?
Teslas don't use LiFePO4 cells. They use an Aluminum-Manganese-Cobalt chemistry that is even different from a typical laptop battery. I believe LiFePO4 cells are used in Priuses. They are also quite popular in e-bikes. LiFePO4 cells main disadvantage is about half the energy density by volume. Properly cared for with thermal management and cell balancing during charging, traditional Li-ion batteries are safe. Rich's buddy was charging the battery with a standard Lead-acid charger.
@@pahom2 Before 2011 or so Priuses used NiMH. That's where a lot of the "batteries don't last" FUD originates. NiMH is only good for a couple hundred or so full cycles as anybody with garden lights can tell you.
One of your videos on USB power packs showed you shorting the center two wires in the cable going to the cell phone made the phone negotiate a higher charge rate. Could I make a male & female USB plug & receptacle with a short going toward the phone that would tell the phone to try to get a higher charge rate from chargers?
Wow thx! So charge Li-Ion baterie about 55 % for storage? I have several cellphones Im not using and I always charge them to about 95 % for storage. So not anymore I guess;)
It would be nice if China made charger modules with protection for the lifepo4 cells like they do for li-ion. A 3 volt under voltage cut off would be perfect. Maybe bigclive could come up with a circuit design if the Chinese won't do it.
I have been watching your videos for the last 6 months or so. I really am shocked at how much I have learnt you're a fantastic teacher.
Entertainment and education in the one package. Clive would make an excellent Technical College / University Lecturer (he beats many of my past lecturers whose delivery was "less than engaging"!)
you're*
"I really am shocked at how much I have learnt you're a fantastic teacher." ... come into my bedroom, i bet i'm a better teacher than him ;)
LiFePO4 delivers a much higher number of charge-discharge cycles while also degrading the least of any lithium chemistry while they're held at full charge.
They're the only lithium chemistry I'll consider for backup power because of this and their immunity from need for an explosion containment pie tin around installations.
they are also immune to being left partially discharged, an otherwise death sentence for lead acid.
Assuming you can get them used, NiFe batteries are pretty much the best possible solution for backup power. Immune to overcharging, immune to direct short (both just boil off the electrolyte. Refill with water and you're golden), and with a cycle life far beyond any other technology.
They're heavy as frig and very expensive when new, bu those are the only real cons.
NiFe is interesting for some applications but they have low discharge current, high self-discharge, and you can only get out slightly less than 1/2 of the energy that you put in. Edison was producing NiFe batteries for electric cars over 100 years ago because they were the best technology available for a long time for such uses.
They are used for motorcycle racing batteries. They can direct replace lead acid. No changes to motorcycle circuitry.
Slightly higher number of charge cycles with very slow and shallow discharges, this isn't magic, you trade off one end to gain something at the other.
5 years ago I picked up a set of 8 solar powered lawn lights (the kind on a small post you stick in the ground). They're powered by one 14430 LiFePO4 each. They've been out there through Upstate NY winters, summers, 365 days a year. 6 of them them will still, given a fully sunny day, burn brightly for at least 8 hours in the summer, around 4 hours in the winter. 2 have significantly weakened.
Call me a LiFePO4 phan.
I've actually been building a portable solar system with a 65x55cm 50W panel and a pelican case housing a controller, a 12Ah LiFePO4 12V battery and water proof connectors so it can withstand rain. I'm glad that I went with LiFePO4 instead of Li-ion
When BigClive and TechMoan upload a video at the same time.... Today is gonna be a good day
And Fran Blanche too!
But Fran is assembling a Heathkit, and I watch that at 2X and still doze off
techmoan is a bit clueless about value for tech tho ,since he uses crapple products
You're right about Techmoan, also he seems to have the reverse of normal money. That is, he can only afford things the more expensive they are.
Thank you for the great videos. This is my favorite channel and has increased my knowledge so I’m not just replacing and re soldering broken components but actually understanding what the components do and why they broke. Thank you so much for taking the time to do this.
I think you didn't mention it, but LiFePO4 cells also allow discharge at freezing temperatures, which might be a huge bonus for outside installations.
I noticed the chip had low operating temps as well. But that was the first one I could read right off the video. ( cell phone watcher) most the time.
So do li ion. I own an ebike and it works in the winter. Not quite as zippy but it does work.
Lassi Kinnunen lead acid has a lot of other downsides, like being a huge brick.
@@johnpossum556 mine in the winter has seen more voltage sag under load and slower recovery. Capacity however has remained similar enough to not really notice.
@Lassi Kinnunen Lead acid batteries also have significantly reduced power at low temperatures so they spec them under low temperature conditions.
I have an e-bike originally designed to run on 24v of SLA batteries, and it's been retrofitted with a stack of two LiFePO4 (i like to pronounce them 'life po four') which have 4 cells in series each, which for all intents and purposes makes a great drop-in replacement for a 12v lead acid battery.
I really enjoy your videos. I am a novice with electronics but have learnt a bit watching your videos. Also found your recent video on Alzheimers disease and caring for your mother very informative. Keep up your good work.
Rich rebuilds used a defective charger on the Tesla 18650 pack which made it go above 4.2 volts per cell. Then bang. It was a great example of how important good electronics are for managing a lithium ion pack.
I don't think it was defective. Just lacking the battery management.
_"I don't think it was defective. Just lacking the battery management."_
When you've got about a thousand 18650s hooked up to it near people or property I think making or arguing over 'distinctions' like this is somewhat missing the point no?
@@bigclivedotcom He said in a followup video that the charger went to high on the voltage. I just used the terminology defective to simplify things and give him the benefit of the doubt that he is not the one that manually chose the incorrect voltage. When you remove a battery block from a Tesla model S my understanding is there is no over voltage battery management as part of the pack so you have to included it your self in your design.
no cell protection on charging is asking for a fire, this one wont be the last and its def not the first, seen people lose their homes and pets charging bikes etc, still to this day no one has built what i would call a proper cell balancing protective charger, bottom balancing has always made more resistant packs, but you need a charger that will bottom balance the cells and then bulk charge stopping when any cell hits 4.2 (4.1), thats how i charge my packs, but have to do it manually in 2 stages as i have a 'normal' charger that wont do both in sequence
For large diy systems the batrium longmon’s system seem to be a good option but for medium to small DIY projects I have not found a product I trust. So when I converted my lead acid electric lawnmower to 18650’s I just decided to do everything manually each time I charge. I use a simple power supply set to the voltage I want for the whole pack and check each cell voltage my self to initiate cell balancing manually. Building the pack with individual cell fuses is also super important for DIY, that has saved me once when a cell reversed and tried to drain the whole pack.
one thing everyone in the comments seems to be missing is that, while LiFePO4 is less energy dense than other chemistries, it has greater *power* density. the electricity within can be discharged faster than other kinds of lithium ion batteries.
Well it can be discharged faster without catching fire, but at even 1C you will get a maximum of 60% back from the battery.
They are safer, but give up performance.
They also keep a more constant voltage.
Graphene lipos can support up to 100 *times* their capacity as a constant rating, especially if actively cooled.
Howling Wolven And where can you buy them? Last time I checked, nothing with graphene made it to the market yet, at least at reasonable prices (except maybe graphene supercapacitors, but that’s not a viable alternative to batteries).
GRBTutorials Hobbyking have a large range of graphene cells for rc models.
"I'll get down closer here so you can watch me have a terrible accident." 😂
I watched that part also, what a coincidence.
@@googleuser859 it's almost as if writing quotes from a video under the video without any commentary is pretty pointless... oh, and in no way, shape or form original
Chris aka Schulbus thank you for said it on our behalf.
@@showmequick2245 even though i can't really understand what you said, you're welcome :)
I was all tensed up...lol
The very flat discharge curve makes them good for powering 3.3v boards.
handy tip!
Is it just a coincidence the 3-3.6V voltage of a LiFePO4 cell pretty much matches the recommended operating voltage range of 3.3V logic?
@@NiHaoMike64 For us casuals, just coincidence. For any hardcore scientist or quantum physycist or chemist, this warrants an entirely new front of investigation!
Or it's just rounded to numbers people can easily memorize.
They also come in standard AA-size which is nice.
I believe it is because you can leave out the regulator, that is all.
Excellent video. I like to tinker with things myself and learning about batteries has helped me. I have two solar street lights. Two things I look for is:
1. How much does the solar panel actually output
2. What type of batteries are in it and are they actually rated for the capacity spec
Well I found that the panel indeed outputs what the specs stated on the listing.
But with the batteries this is where they go cheap to save money. Usually some used grade b cells that are 40-70% rated capacity. Which is why most people find that the solar light stays on for half or less than what stated. Most cases there is more room in the casing to upgrade the battery capacity.
So, two things, one for Clive, one for the comments.
Clive, one thing about the two FETs, you're right about the diode blocking, but that's only part of it. The 'OC' is charge FET, and the 'OD' is discharge. That's how the chip is able to cut current flow when it exceeds a threshold.
As for the LiFePo4, they're 'better' for some applications. One nice characteristic is that you can usually charge them pretty aggressively and they'll take it. I've seen some that will allow you to charge as hard as you discharge. That's great for regenerative braking or hybrids.
I wish they were more popular so the price would go down.
Since you mentioned practicality of solar Christmas lights.. Yay Clive!! I have played with a standard sized garden "solar bank", panel about 95mmX80mm with lithium Ion, as well as many 50x50 with NiMh. The NiMh units all had 600 or 800mAh and "high" operating current of 35 to 50mA and drained the cell whether or not connected to a string of lights. My load was the magnet wired seed/fairy lights that required only about 15mA but unfortunately could not span even one cloudy summer day. One unit that is NLA had 2mA operating I. I imagine that's either about protection from overcharge or poor design. The lithium bank had 8mA drain, auto-dimming, a cheapo 1200mAh cell, and performed well even during the winter solstice near Toronto, Canada. Not super bright, but indeed super pretty. Partially thanks to you I have custom 12/24" pitch fairy lights... Beware of the wasteoids!!
I would venture to say that Rich's battery accident had more to do with his battery pack not having a BMS and possible overcharging rather than the types of cells he had. But nevertheless great video once again!
It was. But it made for a great video.
Hey BigClive, Pro Tip that I use at my Aerospace job; Score the heatshrink and then hit it with a heat gun and let it split itself.. :P
both of my work vans are entirely LifePo4 including the starter battery. Both have auxillary battery systems of 160AH and 800AH respectively and lifepo4 is the only way to go. I can draw hundreds of amps with little to no voltage drop all the way to 80% discharge.
What load do you run with that kind of bank?
@@UniCrafter The 800AH bank runs lighting, inverter, kettle , microwave and bits. I often work on site for days at a time and charge a cherry picker battery from it too, that draws ~60A alone.
The peak draw i have had so far is 320 Amps .
@@amojak ah right, I watch a russian youtube channel and the owner owns a hummer with 1 or 2 banks of 1500AH of lithium, and runs a 40,000w sound system off it lmao
@@UniCrafter i can believe it. I do actually have four 1000AH cells here , originally bought for a van but they are too big to fit. hence i used nearly new leccy car cells instead.
Another point of having two MOSFETs, even if there wasn't the diode issue, is that it allows it to independently block charging vs discharging. When the battery is at its max voltage, you want to be able to prevent further _charging,_ but you don't want to prevent _discharging_ (which would just make the battery useless), and likewise when it's too low, you want to prevent further discharging but don't want to prevent somebody being able to charge it back up to make it useful again...
After watching Rich's pyrotechnic display I think I'd go for these lithium iron phosphate cells for my DIY powerwall. I've got a lead-acid server room UPS and these batteries stack up nicely to 12V.
8:40 "feels like defusing a bomb"
I was thinking just this morning that I'd love to see a Big Clive video about collapsing circuits and other Hollywood bomb tropes.
With fireworks.
And cats.
Thanks for the PO4 because I actually did want to know what that meant. :P
Same here...
Appreciate the video. Keeping the technical withdrawal DT's away over this festive season :) Hope you had a great Christmas New Year. Love your video's Clive.
I'm presently using these grey Lifepo4 cells in a self built 10KwH battery bank charging off of 2Kw of solar panels fixed to the roof of my truck. I control the charge/discharge Voltage via my solar charger/inverter & balance them with BMS boards. They work very well: many times more efficient than lead acid & very long life compared to Lithium ion. With the right charge/discharge profile they may well last a lifetime with just a little power loss that can be offset by adding more batteries in the future.
watched again in 2021 - wondered if I had missed the further investigation of the pv panel in summertime. I am addicted.
Love that Clive watches @richrebuilds too
Nice to see the LiFe cells in things now. I had assumed it was a Li-io 26650 cell.
"That's just the peril of solar panels, they don't put out much power when you need it the most." is a very accurate summary of my experience with them too.
Although I guess maybe if you're in a hot climate and plan to run your air conditioning on a battery buffer + solar panel its output trends will meet your demands better. Technically solar panels get less efficient with heat, but when allowing for some ventilation around the panels the extra sunlight to convert into electricity is almost guaranteed to compensate generously for that "efficiency problem".
A few years ago people would disassemble DeWalt battery packs to get their hands on the A123 cells, which AFAIK use this technology. Major advantage: you can charge and discharge them at ridiculous rates.
The two mosfets used with cell protection chips like that actually operate independently to block in one direction for over-charge and the other direction for over-discharge.
This chemistry is used in cheap solar street lights because the voltage matches that of white leds , often they feed the leds direct with no other circuitry , the flat voltage with discharging keeps light output fairly constant.
You just need to come hang out in Southern California for the winter. We've got plenty of sun for your solar Xmass lights. It's just a pain to string them on palm trees ;)
IIRC Andreas Spies did a bunch of tests with different battery types including the LiFePO4 cells about a year ago.
-Jake
THANK YOU for calling it a "CELL" and not battery. I wish I could make my own giant "CELL" 3.2 volts as big as a trash can.
I use them in the AA form, in pairs with dummy batteries, in high power flashgun units (Sony HVL-F60M, Godox TT685s) . The refresh rate for a 1/1 discharge is about 1", which is much less time than when using NI-MH (or seldom Alkaline). The downsides are the relative low energy density, the (sorta) special charger needed and the inability of the flashguns to cope with overheating... the last I suppose is probably due to the flash designers expecting a longer recycle time from 'common' batteries :-)
I was very pleased to find them, albeit a bit pricier, in a big french retailer currently operating in Greece, in the spares section of solar garden lights!
LFP batteries from Battle Born/Dragonfly and a few imports are being used in RVs. The BB10012 is a 100Ah 12V pack in a car battery form factor that replaces the deep cycle coach/house batteries. LFP in a 4-S configuration yields a more compatible (than Li-Ion/LiPo) 12.8V nominal voltage and a range of 14.4-10V (BMS limited) which works well enough with lead acid charging systems. More stable and safer than Li-Ion with a 10 year warranty. LFPs are fussy about temperature and go off-line below freezing (25 degF for charge circuit, lower for discharge) so some owners move them inside the coach since there's no hydrogen or corrosive gasses venting out. The cost is high initially but lower than LA over their lifespan. Charging efficiency, minimal self-discharge, usable capacity, and light weight crush lead acid performance.
They're popular for ham radio for the same reason, most radios are designed for 14V maximum voltage.
I got a 20Ah 36v LIFEPO4 batttery in my ebike, using it with a GNG electric motor kit.
I put it together myself, mid engine with the belt drive, great in hills :)
The LIFEPO4 batteries shall be good and i cannot complain yet, i has had it for like 3 years.
I put a saddle pack over it so it looks nice under it on the rack.
Tesla use the 18650 batteries i has read somewhere.
That other video reminded me of a fire at the local fireworks factory. I was having flashbacks to the great war...and i wasn't even alive at that time. Impressive, very impressive.
i love your voice - i know nothing of electronics, but i put your videos on just to be soothed
I started buying only LiFePo, because in Arizona and West Texas, the denser/standard lithium battery packs for jump starting a car or charging a phone will expand. Never had one explode, but it's not worth the risk. I even used a permanent car battery size for a few years, and it had no trouble in freezing 🥶 or burning 🥵 temps.
I think it's touchingly patriotic of Glaswegian officials to have earnest meetings and a few experiments about the possibility that Glasgow in December might be the perfect place to utilise solar power. Us Sassenachs that have visited Glasgow in December probably wouldn't have wasted our time in the meetings - but love of country is a powerful and mostly admirable thing.
The proposed design would have been super low current sparkling LEDs around existing planters. But the solar energy available was surprisingly low.
For EV's Tesla is not using LiFePO4 chemistry in its battery cells, but NCA. For model S, the cell type is the 18650 (like the purple one you hold). For model 3, it is also NCA chemistry (LiNiCoAlO2), but in the 2170 (21700) cell model.
Ya know it's gonna be good when Clive breaks out the explosion containment pie dish
Strange how words bring back memories of our youth, for example you said slit, and the old tongue twister "I slit a sheet; a sheet I slit; and on the slitted sheet I sit!" rushes through my mind. Don't know if that one made it to your side of the pond or not.
It did indeed. They use it in drama colleges.
Another advantage is the voltage. 90% of the capacity they stay between 3.2 and 3.4V tange... so you can power 3.3V chips (Arduino projects..) directly.
At the same time it’s a disadvantage as it is impossible to guess their charge level by voltage (works somewhat for lunch-ion) as the voltage sits so close to 3.3V between 30% and 95% of capacity.
Military likes to use such batteries due to their tolerance in case of improper handling.
Some people here say they are expensive. Can’t confirm that. I’d rather say they are cheap. Many types are tested for 5000x and more cycles, taking this into account they are easily 10x cheaper in kW/h
dc -dc converters are widespread anyway
FOR THE RECORD: I AM VERY INTERESTED IN 18650 AND LARGER TYPE BATTERIES.
THX FOR THE GOOD CONTENT.
Hi Clive, I'm confused. I think you are saying at 1:44 that lifepo4 batteries are used in electric cars because they are safer, but they can catch fire as in the rich rebuilds video. But are tesla batteries Lifepo4 ? I thought they use 18650 batteries like the purple one you are holding, not the grey one. And thanks for testing all sorts of electronics, love your video's!
Thanks Clive. I learned something new today.
YES at last a video about Lifepo ! Do you know the LITO batteries ? Lithium Titanate. It's a very cool battery and i think it would be fun to test and open. And you could do a series on batteries, because there are so many different kind, maybe just the interesting ones.
4 of these make great replacement for 12 batteries in kids toys and UPS. UPS batteries often kill them selves when used. These cost a fortune but well worth it you have multiple power failures and let them run to zero.
This streetlight will work fine closer to equator. Because of the lack of distinct winter season with many dark hours. Else you may add low voltage from mains via a "winterswitch".
The expert Clive quickly make the device safe before continuing with the disassembly...
Great video , thanks, it will be interesting to see how this technology develops. It seems to have a lot of potential.
5 years later & nobody else spotted this, nicely done, but falling a bit flat this late.
It is amazing how much energy these modern batteries can hold, I assembled a 3S-3P 18650 pack this morning and just held it in my hands marvelling at the fact it has about the same, if not more, energy in it than one of my 12v SLA batteries, but also the fact that if the SHTF and the things went boom, they'd be a lot more lethal than said SLAs... :S
On the plus side, they won't spray acid all over
So in the first video you measured the battery is that how they sell them by size and capacity. Last night I did a quick search on lifepo4 on amazon they seemed 18850 was popular. It was late I didn't watch your quality video til this morning. Cheers from coldass, kansas.
18650 cells are by far the most popular cylindrical cell size.
I had a funny Big Clive moment today (Jan 4) I wanted to share...
The blower motor resistor pack died on my car this morning, and I was stuck with only the Hurricane setting for my heater. To add insult to injury, the servo motor that opens the various air doors has been bad for a while, leaving me with only the dash vents, but that wasn't an issue until I was stuck with the Hurricane-or-Off option. Down to the auto parts box store, plug the new resistor pack into the wiring harness and leave it dangling until I get home and install it properly (I've done it with the old coiled resistor type, so I figured this would be OK)... I had all fan speeds for about 45 seconds, when the new resistor pack failed. I look down at it and realized there is a thermal disconnect, a copper-ish tab soldered to another terminal so it fails open when overheated.
My Big Clive Moment? I look down, and say (with a very poor accent) "Not to worry, I'll just reflow the sahl-der when I get home."
And I did just that, with my 1970s unfused Weller iron. And my fan works as it should, now that I installed the resistor pack deep within the bowels of the modern car dashboard where it can be cooled by the airflow as it was designed. :-)
we use LiFePo4 cells as a 12v starter battery in aircraft. partly for low temp performance, but mostly because they are bulletproof. we shot a nail through one and it just sat there and took it. still it has to be in an aluminium bunker because boeing cocked it up by using LiPo's without adequate protection and without armour in the dreamliner.
lifepo is genius for some applications ..
The 26650 from a123 system is the best vape cell on the market 140amp burst
There is probobly LTO cells that is better, but they are really hard to get hold of
That's a lot of vape.....
Went and looked at the video. That was quite the spark show.
I truly enjoy your videos! keep them coming bud...
A123 systems made a nice 26650 cell, 2500mah and could do 60c discharge which is great for RC cars and even planes where you don't need long run times, they allowed extremely fast charge too for the time, I used them for years and still have the packs I made and are still working perfectly.
Lipo cells are much preferred for power density though but they don't last very many cycles in comparison.
In the words of my favourite comedian Billy Connolly! “Hey guys I found a even rainier place” good old Scotland
I've been playing around with some solar charging of batteries, mostly using lead/acid batteries that I already have. One of the reasons is faking more daylight in my greenhouse (which is why I started making my own version of your RGB LED controller!) Another thing is a solar light for my front gate, walkway and front porch.
For your use, I would suggest spending a bit extra on deep cell gel batteries! Not only will they last much longer, they are designed for constant drain/recharge use. They are more expensive no doubt, BUT in the long run you will buy less of them over time.
Martel DuVigneaud plants grow best with red and blue light. Witch to us is a pinkish purple. They will grow with red and blue. But best with the combo. The blue UV LED's not true, complete UV, but dip into the wavelength of uv. With a red led that also peaks in to the infrared spectrum. Would likely be closest to what the sun provides. Giving only what the plants needs. Not wasting power on other wavelenths of light. Amazon sells the led lights with red and blue for plants. I'm planning a small green house. And plan to use about 10 watts of red/blue LED's per plant. With about 300w solar to start with. And 400 ah in battery. Along with a pwm dimmer. Maybe one for each colour. Allowing to adjust colour and brightness. Sorry for rambling!!!!
@@Malakie Yeppers! I'm experimenting/learning just using old deep cycle SLA batteries that I pulled from and replaced in UPSs where the only other reasonable option is to dispose of them (already significantly reduced capacity.) I'll get new batteries when I'm a little more sure of what I need and what I'm doing. ;)
@@jamest.5001 Yes! That's my intent! I plan on alternating strips of the red/blue grow LED strips and white (maybe 3:1) so if I need I can also turn on white light for visibility for me at night. I'm also planning on assembling a passive thermal heat system: a tank of water in the greenhouse with an out-feed pipe at the bottom running outside to the bottom of a black poly-pipe that snakes side-to-side up an incline and feeds back into the top of the water tank. Y'know, just to give extra heat at night. :D Total capacity of the solar panels, batteries and LEDs plus the thermal system are all still things I'm experimenting with! :D
Martel DuVigneaud that sounds awesome. I'm thinking of a similar , supplemental heating for my off grid house. I have solar power, and a generator. With 4 t105 style golfcart batteries, and 4 huge L-16 leadacid. And 1400cell liion battery bank. That I use separately. Mostly use the lead acid for backup, and use the middle of the liion. So I expect about 40-50% capacity in 15-20 years. I cycle them from 3.1-4v per cell. And in a emergency Can parallel banks when voltage is equal. Or use the generator. I hope to get a tiny hydro electric generator going. And maybe a wind turbine. If I can get a constant 500 watts it would help alot. I'm trying for 1200+ watts on each. There is weeks without sun here. Sorry for all the rambling!!
Damn bigclive, how do you keep reading my mind? First a few days ago I was thinking of asking how you test battery packs and you post a video, and now 5 minutes ago I was literally just looking at an ad that has a whole bunch of these batteries, but much larger.
GET OUT OF MY MIND!
Dude... we need to get you some sort of ceramic, or space age plastic blade to cut these things open with! My heart can't take much more of this!!
I have though seen many of the bigger LiFePO4 cells swell and puff up after a few years, some variants of these seems pretty sensitive too
They do swell and potentially vent when they fail. But they don't ignite in the same way as standard lithium cells do.
@@bigclivedotcom indeed. You could see the initial swelling as an immediate reason to change them out before they get to dangerous levels which is a good thing but in the end both kinds are rather sensitive if you go beyond their specifications in any way
Hello Clive, you should have a look at Lithium titanate aka LTO batteries. They are even more long lasting and more inert.
I use 3x26650 LiFePO4 in a power pack for my instrument effects pedals. The pedals handle the 10.8v immediately after charging fine and at the pack stays at around 9.0-9.9v for a long time. Much safer for charging/handling, and less stressful on the 9v pedals' circuitry compared to the alternative higher voltage Li-ion alternatives.
The problem with solar is it doesn't work in the dark.
However if you use thin film solar panels you can get probably close to full power in un-idealistic situations. ie. bad angle to the sun, overcast, partial shading etc. Problem is they cost a little more and are larger in size, they have a shorter lifespan and are less friendly to the environment but they should work in Isle of Man or any other overcast area. After that obviously you just size for the application depending on how many daylight hours you have.
Clive you really should keep a bucket of sand nearby in case of fire. Maybe a plan to drop the battery in one bucket and pour sand on it from the other.
Very interesting. Thanks Clive.
That is some quality stuff. Great lessons learned. So is this circuit diagram a smaller version of BMS ? I mean, can I use many of these small circuits in a battery pack instead of a BMS ?
I am a Ralfy subscriber for years and I learned about you through him :) keep up bros
Hey Clive, are you sure Tesla packs are LiFePO4? As far as some articles describe, they are using LiNiCoAlO2 chemistry in the new 21700 cells. Older packs used regular 18650 cells (with minor tweaks from Panasonic but still regular Li-ion chemistry).
I got it wrong. They don't use them, but a lot of other electric vehicles do use the technology.
You might like to get a ceramic knife or any other non conductive blade material you like. Sometimes you can get Soviet scalpels on ebay which are equipped with sapphire blades.
Tesla uses Nickel80Cobalt15Alu5 batteries (plus minus something; The more Cobalt, the more power they have, but it's getting complicated here), which is why they burn so well. Also, they charge and discharge them with a lot of power, you can't do that with your standard lithium cell. We're talking 2C or more here (which is, btw, quite dangerous).
Tesla uses NCA Li-Ion batteries, not LiFePO4.
They aren't used much for plug in EVs as the specific energy density is lower resulting is massive packs.
Well, I would sacrifice the energy density for a car that doesnt need its most expensive component replaced every few years and doesnt occasionally explode.
LiFePO4 IS a Lithium Ion battery...
@@Chuckiele In any proper EV, the batteries are heated and cooled to keep them at the optimal temperature for long life. So they don't die nearly as quickly as they do in things like phones and laptops.
@@lobsterbark Yeah but still far from ideal.
Besides the unwillingness to burst into flames, Their higher number of charge cycles is only on paper better than Li-ion. If you charge a Li-ion cell with a voltage range comparable to LiFePo4, it gets the same number of cycles, so energy density, and cycle life is very similar in all but the most demanding applications, Cost Wise LiFePo4 have an advantage.
You didn't cover the operating temperature.. think it works at a lower temp then most batteries. But can't remember. 🤔
The lower nominal voltage of 3.2v also means the W/h rating will be lower for the same mah capacity. Mobile phone batteries are actually using chemistry now that nominal voltages are rated as high as 3.9v with a full charge voltage of 4.4v
Lithium Ion Vs Lithium Iron.
What a wonderful language we use.
@bigclivedotcom
Clive, stop it! Enough! I'm trying to get work done but you keep posting excellent videos that I have to watch. You're killing my productivity. ... Oh, to hell with it. Keep 'em coming.
I have those same purple battery's for my vape, i have had them for two years and no noticeable loss
Whenever handling Efest cell, you should have the explosion containment pie dish ready! Even looking at it may be dangerous...
given how solar isn't going to keep ya warm in the winter anyway, can you look into thermo-electric generators? You'll get to talk about Seebeck effect & how your stove can keep the batteries charged
thankyou Clive.
Clive, I was wondering if you could get hold of the advent calendar helicopter that Stuart Ashen and Nerdcubed(Dan) Built over Christmas as it's not working? It would be interesting if you could take a look at it =)
Big Bob is one of the smartest guys I seen but Tesla does not use lifeo4 battery’s they use the regular Lithium ion cells , and that is why in that video he has link to it started to explode but Tesla is the only company that has made the Regular lithium ion cells less dangerous than any other company due to the battery management system and the way they place them
I also think that electric cars, especially Teslas, are using Lithium-Polymer based cells for their battery packs, because that's the only way how they can get something like 100kWh into one car. Maybe car manufacturers like VW, which used to build only internal combustion engines, playing it safe on electric vehicles until it's almost too late, and now offer electric cars with ridiculously low ranges per battery charge, use LiFePO4-batteries for their cars.
The most significant difficulty with LiFePo4 is cell balancing. Once a cell is charge it basically will float up in volts and not pass any more current through it. This means if one cell charges faster than the rest it will prevent the rest charging fully.
The other issue is not letting the cell discharge below a set voltage as it will damage the cell, so you need protection per cell for charge and discharge as well as balancing (a load switched across a charged cell so the rest of the cells continue to charge).
You can match cells to minimise this as an issue and suppliers like www.ev-power.eu sell such 12V monoblocs and i use them here.
A BMS takes care of it all.
It's even worse with Li-Ion cells. Without BMS, the weakest cell in series will never reach full charge, an the strongest cell will overcharge, causing degradation or fire. A Battery Management System is an absolute must for lithium battery packs. Even if you start with matched cells, they will become unbalanced. With LiFePO4 cells this is inconvenient. With Li-Ion cells it is dangerous.
Hi Clive,
What's the temperature stability like? Li-Ion are terrible when they get cold, is the LiFePO any better (with this being an external device)?
BTW, is that 18650 you're waving about really 3100mAh? I tend to look at anything over 2600mAh with suspicion unless it's come direct from a manufacturer.
its a fakey 18650 from china. but yes you are correct, the real high capacity ones only come direct from a trusted route
@Dave Micolichek i have them as starter batteries on my vans, they start fine below zero.
Also a Rich Rebuilds fan.
These things last ... forever. I've put a LiFePO4 pack of 48Volts (52 actually) with an external BMS on my electric scooter... back in 2007. Still charges today like a champ !
Somebody show me a normal Li-Ion battery of a phone that lasts reliably more than 5 years...
hi a tp5000 module can be used to charge a lifepo4 cell 2A switching charger can also be used for lipo/li-ion
I would love to buy some dedicated LiFePO4 protection boards but the usual sites lump them into the 18650 boards. I think I found some.
I wonder if the "true switch" back-to-back silicon MOSFETs are necessary now that GaN Mosfets without body diodes are becoming more commercially accessible now. Silicon is obviously cost superior, but is that the only reason?
Teslas don't use LiFePO4 cells. They use an Aluminum-Manganese-Cobalt chemistry that is even different from a typical laptop battery. I believe LiFePO4 cells are used in Priuses. They are also quite popular in e-bikes. LiFePO4 cells main disadvantage is about half the energy density by volume. Properly cared for with thermal management and cell balancing during charging, traditional Li-ion batteries are safe. Rich's buddy was charging the battery with a standard Lead-acid charger.
Yeah my e-trike uses LiFePo4 batteries at 36v. However, it used to have Lead-acid batteries and I converted it.
My portable mobility scooter uses LiFePo4 batteries @ 24v. Only 12Ah but cost £300 to upgrade from lead acid.
My new Hyundai Ionic Hybrid also uses LiFePo4 I think ?
I was wrong, Lithium -Ion Polymer.......
@@pahom2 Before 2011 or so Priuses used NiMH. That's where a lot of the "batteries don't last" FUD originates. NiMH is only good for a couple hundred or so full cycles as anybody with garden lights can tell you.
One of your videos on USB power packs showed you shorting the center two wires in the cable going to the cell phone made the phone negotiate a higher charge rate. Could I make a male & female USB plug & receptacle with a short going toward the phone that would tell the phone to try to get a higher charge rate from chargers?
Tip to remove heat shrink.
Make a small cut.
Heat it up withva lighter and then you can pull it off easily.
For hot glue use medical alcohol.
Wow thx! So charge Li-Ion baterie about 55 % for storage? I have several cellphones Im not using and I always charge them to about 95 % for storage. So not anymore I guess;)
It would be nice if China made charger modules with protection for the lifepo4 cells like they do for li-ion. A 3 volt under voltage cut off would be perfect. Maybe bigclive could come up with a circuit design if the Chinese won't do it.