Make your own "Powerwall" (Big LiFePO4 Battery Pack!)
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- เผยแพร่เมื่อ 21 ก.ย. 2019
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Here is where I got my components (for the "Powerwall") from:
www.energusps.com/shop/produc...
www.ev-power.eu/Winston-40Ah-...
www.voelkner.de/products/3899...
Useful websites which were shown during the video:
www.tesla.com/powerwall
en.wikipedia.org/wiki/Tesla_P...
In this project I will be creating my own DIY "Powerwall" which is basically just a container filled with batteries and a BMS. Along the way we will learn quite a bit about LiFePO4 cells and about the budget friendly, yet powerful Tiny BMS. At the end you should be able to create your own big and safe battery pack that can be for example used with a solar off grid system. Let's get started!
Thanks to JLCPCB for sponsoring this video.
Visit jlcpcb.com to get professional PCBs for low prices.
Music:
2011 Lookalike by Bartlebeats - วิทยาศาสตร์และเทคโนโลยี
Correction: At the end of the video I was referring to Wh/€ and not kWh/€. Sorry.
First
I may be a giant robot... But I really like you human!!! Can you make a portal 2 turret next please?
@@LoganDark4357 congradulations... I bet you were waiting very patient human.
I'm not actually human tho
Also, really all I did was visit my recommended and see that this video was uploaded 4 minutes ago when I checked :p
Those are some oversized Legos you've got there.
Great video as usual.
Er bekommt bald auch eine Abmahnung von Lego, sowie Held der Steine und Bluebrixx! 😂
Er bekommt bald auch eine Abmahnung von Lego, sowie Held der Steine und Bluebrixx! 😂
I actually thought that those were Lego.
😂 i can't with u
_"After measuring the dimensions of my battery pack, I choose a slightly oversized electrical cabinet"_
Pick nearly 3 times the size of the battery.
Joke aside, this is a really well thought solution. Just a small tip: when pronouncing part number, use dash instead of minus. Makes more sense.
Big electical cabinets are good for people like him, who never stop improving their projects. More space for additional batteries.
German specification
How about using the NATO phonetic alphabet for the maximum cool factor?
He'll probably add more Batteries in the future
more room for upgrades and also let's the heat rise away from the batteries 😁
500euros is too much but 460 isnt xD
499 is the limit
It seems GreatScott
lives in Germany. The minimum salary in Germany is €1593 per month (pre-taxes). I also live in Europe. But here the minimum salary is €600 and the avarege is €943 also pre-taxes. So, some projets that GreatScott
presents in its channel are simple not reachable for some people.
@@jpedfonseca y'all live nicely
In Croatia they think that 500 euro per month is ok even tho it's barely enough to pay the bills and keep you alive
@@blackturbine you are lucky man, in Morroco the governement thinks that 350 euro per month is more than enought !!
Apparently we're competing for whose country has the lowest minimum wage so, here in Brazil it is roughly € 220 (and believe me, a lot of people live with this or even less). So this build by GreatScott is REALLY expensive.
Rated charge/discharge Cycles of LiFePO4 are much more than Li-Ion. So you made a good choice.
Good build, but it would be wise to drill a small 3-4 millimeter hole in the bottom of that enclosure, if it doesn't have one already
Waterproof it may be, but vapor can get through far smaller holes, and then condense inside, at which point it can't escape the waterproof enclosure, especially with the daily thermal cycling in an unheated area like a garage.
Plenty of electrician type people suggest doing that (Big Clive for example) - it's not uncommon to find a seemingly perfectly sealed box resembling a fishtank. It doesn't really compromise the waterproofness - water drips/rains from above, and it lets any water that does condense drain out of the box.
Doubly so because it's filled with batteries- LiFePO4 might not be as prone to catching fire as other chemistries, but in the event of a catastrophic short it's still going to heat up and vent gas, at which point the pressure inside a sealed enclosure could build to dangerous levels/blow up, a little hole would allow the vented gas to dissipate more safely
Great suggestion
I just dropped by to thank you for being my teacher during my journey into the world of engineering! ^^ I've learned a lot from your videos! =)
Energy created? Dude, I'm high and GreatScott just broke THAT Rule! This is awesome! You gotta be friends with GreatChuckNorris.
That's another great video.
I would be putting the temperature sensors in between the batteries though as the ones in the middle will get hotter.
I'd also drill a small hole in the bottom of the cabinet as a vent for gas build up and also as a moisture drain.
I think you've convinced me to make one myself though!
LiFePO4 batteries are usually sealed and do not produce any gas during normal use, so there would be no gas build up to vent (unless they were overcharged or damaged).
(This can be a concern with lead-acid batteries, but lithium batteries do not have that problem.)
Thanks so much for finding that BMS manufacturer, I was scared to use the one I found on eBay for protecting my high power battery.
Finally. Now complete the drone. Good video as always, keep up the nice work.
Good project as always. A little tip I picked up a few years ago regarding getting roll plugs into a wall: put a screw in a couple of turns then hammer the screw end. This saves accidentally ruining the plastic roll plug.
I am sure Jehu Garcia would be very happy to watch his German counterpart 😆
Yeah, I'm very interested to hear what the power wall community thinks of that bms. It's not a manufacturer I've heard of before
@@gelu88 Agree, and I think the world needs a little open source hardware in this domain. Hopefully @ladyada is also listening...
Your garage has more tech than my whole house :D
When your charging your 6S3P power bank when the video gets uploaded. That's for the wonderful content once again!!
Thank you SO much for this information. I did not know this particular quality BMS existed. It is just what I need for my project.
Hi! Great project! I think you should use li-titanate battery (LTO) to be able charge at low temperatures. I used toshiba SCiB cells for a similar project.
P.S. Make sure there is no direct contact of copper and aluminum at the terminals.
Hi Great Scott!
I've used an earlier version of these cells before, they absolutely need mechanical constraints, otherwise they bulge over time and cell DCR increases. Highly suggest sturdy end plates and either two straps or long bolts to keep the batteries from expanding. Topologically they are very similar to polymer 'pouch' cells internally.
If there not aloud to expand they will pop lol
@@crf80fdarkdays Bullshit. Lol.
@@crf80fdarkdays Not true, actually. Using mechanical constraints to keep lithium cells from expanding during use is actually very common practice, and actually does not harm the cells at all (on the contrary, it actually generally improves their performance over time).
Great video! Very helpful throughout the whole process, very well explained. And a very cool and useful DIY project!
Fantastic info and build, thank you for your time making these videos, much appreciated!
I really liked that powerfull outro :) I will see you next time!
see you NEXT TIME!
As always, well explained step by step explanations. Great video!
Heck yeah! Finally clearing my suspicions :D
Nice! I think you can put the thermistors in between cells 1-2 and 3-4 (there seems to be a 2..3mm gap). This way you sense all 4 cells and also sense the hottest part (the core). Regards!
Hey Scott,
thanks for your interesting Video! I was also interested in this Winston LiFePOs. So I know some about them.
It is absolutely necessary to strap the cells together for example with threaded bars to prevent them from bending.
Also you forget the initial balance charging. Normaly you should connect all 4 in parallel and charge them to 3,7 Volts until the charging current reaches 0.1a or less. Subsequently you should store them in parallel for about 24h.
But you did a great job. Thanks for the interesting project.
Thank you for doing this, much cheaper than most. I'll be doing something like this someday.
super great video info and analysis from absolutely the best channel on utube thank you keep up the good work
~ The 76 page manual was quite interesting. Such a nerd. I’m jealous.
Interesting the LiFeYPO4! Nice video as usual :)
its great to listen to this detailed explanation even tho im not quite a listener
video quality and sound quality are awasome .
Interesting project. I thought about adding a backup energy source to my hone and now leaning towards a solution like this.
Per dollar you cannot beat lead acid. his engineering requirements in this video are a bit contrived so he can show us a different battery chemistry.
otm646 lifetime cost for lead acid and liion (nca/nmc) and lifepo are about the same. Lithium is more convenient beacuse you dont need to touch them for 10-30 years but lead acid is great for short term projects and extreme cold.
Yeah lifetime cost is about the same for all three.
@@otm646 SLA is REALLY expensive in the long run as they dont last as long.
@@otm646
If your lucky lead acid will last you maybe 2-4 years when cycled each day (which it most likely is with solar power), LiFePo4 while maybe more expensive for a given capacity can last you atleast 10 years to maybe even 20 years. So in the longrun it is actually the cheaper solution. Also you have the problem with lead acid that the capacity decreases steadily during its lifetime, while LiFePo4 and LiIon stay for most of their lifetime at a quite constant level and only start to decrease fast at the end of it.
LiFePO4 is my fav battery chemistry.
I have a few emergency vehicle jump start packs that use these and I use for everything except jump starting my car. They make awesome power supplies.
*Another amazing video!*
*I really appreciate your work!*
after watching your videos for a while, i trust you with being able to make this and giving us good instructions to replicate the safety of it. im hoping to apply it to the home i hope to eventually build, with generators and other home made circuits.
I was the guy asking for this project, so thanks a lot!!!!!!?
@Wischmopps what the hell is wrong with you?
3:00 Wusste gar nicht dass deine Garage auf der Zugspitze steht :D
das ist so wahr sogar im hochgelegenden saarland ist es nicht so kalt
Verdammt das wollte ich kommentieren 😄
-20° alter ich bin froh, wenn wir im Winter mal die 0 schaffen :D (S-H)
Wusste nichtmals, dass es aus Deutschland kommt?
ich auch nicht xD
-20 habe ich in Deutschland noch nie gesehen/gefühlt
Thanks for this video. I think that it is a great project to undertake. I provide power in my garage using old APC UPS units. I cut down the main board in the UPS, isolating the charging circuits and the mains input. I replace the charging circuit with the solar charging circuit from my solar panel controller and placed a switch circuit in front of inverter. My solar panels charge the batteries inside the UPS and 4 other batteries that I have hooked up to provide the 24 volts the inverter uses. It was a simple system to build and it allows me to run my grinder and drill press along with all of the lighting in the garage. I tried replacing the lead acid batteries with battery banks made from recovered 18650 batteries from old laptops. The systems work well with these batteries but I have far more lead acid batteries than 18650 banks. I think I will try LiFePO4 batteries in my next UPS rebuild.
This was a great video, very inspiring! Thanks for making it!
I added a tiny controlled heater in my LiFePO battery box that keeps the temperature over the -5 degrees minimum temperature.
Definitely worth doing. Lots of industrial control panels have heaters inside for all sorts of reasons.
Christie Nel But is -5°C the actual minimum?
@@johnfrancisdoe1563 That is what the datasheet says. Below -5 and warranty void. The batteries might actually record this, too. I'm sure they'll be fine in reality, but I know they don't like high currents when cold.
In other words, program the thermostat to maintain an air temperature of 23-113°F (-5-45°C), preferably on the lower end of that range (-5-20°C, 23-68°F).
Christie Nel Can you recomend some heater, I have no idea.
I don't suppose that You live on top of Zugspitze :D
Vojtěch Höll Maaan ich will seine Videos in Deutsch 😂
@@gandalf1783 Was ist "Videos" in Deutsch?
I’m pretty sure this man made a bomb
Mann, ich wünsche wir hätten mal im Winter so viel Schnee und Kälte :)
9:05 "But it also surfills all kinds of safety standards"
Yeah, but the marked "safety standards" are only model numbers of other enclosures :D
Great video as always. Perhaps you could look into lithium titanate (LTO) batteries as well.
I was going to suggest/ask about the same thing. Like these winston-battery.en.made-in-china.com/product/kBREtdwSaQGJ/China-Lto-40ah-Battery-Yinlong-Lithium-Titanate-Battery.html I just learned of their existence recently and am not sure of all their use cases.
Efficiency of this chemical composition is rubbish. I believe it's about 80%...
@@xmicks a shit ton of charging current tho...
Really awesome work, dude! 😃
I think about making something like that for a long time!
We would expected the DIY way👍
Thanks for sharing😀👍
Please mind changing those A2-70 stainless bolts on the poles of the batteries. Stainless has a very bad behaviour - not only it has a bad temperature and power conductivity, but also it promotes the so called contact corrosion (So the copper bridges will corrode way faster). I'd recommend to change those with copper bolts.
Which stainless is a poor conductor? There are over 50 varieties and I am unsure which series my Locomotive uses. Egads!
@@geraldhenrickson7472 A2-70 for example. You can check the resistance for example with a multimeter and compare the bolt with another one made from classic 8.8 grade steel. :)
Isn't brass what you want so you can actually torque the sucker?
Now it's official: Great Scott hates pipe fittings. :D
Its common in germany.
Great Scott , this is awesome , I'm sure this will provide a suitable auxiliary power source for a pc should a power outage ever strike , thank you for the video
As well as when you say "see you next time". I hit the like button👍👍👍
I didn't know you where living on the Zugspitze ;)
9:32 I seriously thought he was sawing through his finger for a second there.
I make lithium battery packs. You get a thumbs up from me for doing a good job designing and building this power wall.
how is this a thumbs up? on the same webshop you can buy 12 batteries with matched cells so you dont need bms and save 200 euro on a overpriced bms.
@@SupremeRuleroftheWorld the bms may be over priced, but most manufacturers recommend a bms be used, even with matched cells from the same batch because as the cells age, they can slowly drift apart from each other due to slight voltage imbalances, and can literally become different capacities.
Stunning bud. Thanks for the info.
Next Mppt charge controller Diy Or Buy
The code is the killer for that - how many will understand the algorithms?
@@kennmossman8701 Coding is a pain in the ass
Victron is pretty good stuff, I'd recommend it
There are great commercial modules and as cheap as the BMS he used for the batteries. I think the best is to buy a cheap commercial, and tinker it a little to failproof it further
It'll require PIC microcontrollers...
Its worth saying that technically all chargeable lithium cells is lithium-ion.. that would include LFP and LTO batteries ... But LFP and LTO is usually specified due to they not complying to the standard voltage of other lithium batteries.
For lithium carbon there is really four common types. LMO that is very safe, but other vice not special. LCO that have a lot of charge cycle, but other vice not special. NMC that is pretty much a combination of LMO and LCO, having both advantages, but a slightly lower capacity and NCA that is a variant of LCO with doped with aluminum to gain additional capacity (about 30%), but loses cycles..
Tesla original roadster uses both LCO and NCO batteries... that is some cars have one variant, some cars have a other. All newer tesla cars have NCA battery only. That is why the 85kWh Tesla S and the 54kWh Tesla Roadster have about the same number of cells, despite the S modell having quite a bit more capacity.
Now there use to be two powerwalls. A 7kWh and a 10kWh modell. They had the same number of sells. The 7kWh modell supose to have NMC cells and the 10kWh modell suppose to have NCA batteries. The NCA modell magically vanished from the market. The reason is probobly because it simply didn´t last. The 14kWh power wall is simply a 7kWh modell with 4 pack of cells in steed of 2, using NMC only. When tesla used 18650 cells they packaged them in packages of 5kWh each. Now they use a other system to pack the cells more densly.
Anyway this is fairly important, because NCA batteries usually just do about 700 cycles. (20-80% full capacity equivalent), LCO does about 1200 NCO dues about 2000 and LFP does about 3000.. LFP is also much more resilient to deep discharge and overcharging, that NMC is not. LTO is claimed to do 7000 cycles
Nissan leaf gen 1 used LCO batteries, but in Gen 2 they swiched to NMC increasing the lifespan from 1200 to 2000 cycles, simultaneously increasing the capacity from 24 to 40kWh, same time increasing the life span of the battery with almost 3 times.
My point is... most 18650 cells look identical.. but how they work is quite different.
most 18650 cells look identical.. but how they work is quite different...................a point that most people miss entirely
@@kennmossman8701 Well... i guess you you have to look at the markings
Thank you for a very informative reply. I really appreciate it!
awesome scott i enjoy watching your videos the greatest diy master
Very informative video. Especially with the prices. A lot of ppl do not provide prices. Good
I hope you 3D print a case for that bms. Kinda worrying it just taped on the side of the battery
If somthing goes wrong with that much power behind it only metal woud posibly help
i only trust old school lead acid... tough and never explodes and fires up like lithium
@@fidelcatsro6948 did you watch the video? He is using lithium iron phosphate batteries
@@jackwyz22 yes ...
@@fidelcatsro6948 well except for hydrogen fires
As a real electrician, watching some of these installions hurt my soul.
Nice Rittal cabinet, those aren't cheap...
You have any recommendations to improve the system or cut out some cost
@@avigetsbored well since GS makes loads of money off these videos, he could purchase some pvc elbows
Or at least the advertiser could have given him some since this whole video is clearly a plug
Great video Scott!
As usual great work congraturations
I would like to use this battery in a motorhome. What is the correct way to charge this type of battery with the engine alternator?
th-cam.com/video/NShywIH_meY/w-d-xo.html
th-cam.com/video/EcVjPap9dkY/w-d-xo.html
youc an just put it in a car. no problem. but use a automatic relay: www.ebay.com/itm/Voltage-Sensitive-Relay-VSR-Automatic-Charge-12v-125amp-Dual-Sense-Caravan-Solar/283620988475
I use a dc-dc charger with a lithium charge profile, most alternators really aren't up to charging lithium batteries directly. They have a very low internal resistance and can draw high currents.
now iam early here
GREAT video amazing can you do a video on class d amplifier working if possible
Thanks in advance
Already made the video.
@@greatscottlab yup i have seen it and is very informative but on like specific model
tda8954th 420w mono like this
if possible
@@Davidslabofficial he doesnt usually do repeat videos. Especially not on such specific devices. This channel is for general knowledge that can be applied across the entire spectrum of technology. C'mon Dave, you got a lab, turn out a video for us on the subject!
@@ryanmalin yup thats why i write if possible
i have some videos on my channel but idk if you like them or not
but if you subscribe me it will help alot
if you want to do
if will be making videos on reviews and some electronic stuff
BUT thanks anyway
You just do everything I was dreaming about...
Great work, dear Great Scott!
Should have mentioned in the calculation that the usable capacity of lead acid batteries (especially at high discharge rates) is only 30-50%
You will need much less of lifepo battery capacity. That will make the system much more cost effective.
Power Brick
Power Wall
Power House
*Power Bank*
Walter Comunello Power tools
As usual
Great video!!!
Love the measuring tape
WARNING!!!
it is true you can DISCHARGE LiFePO4 batteries in cold weather...
But NEVER charge below 0C....
Permanent damage to the cell will occur.
Make sure your bms has a thermal cutoff
And you can apparently charge these LiFeYPO4 batteries at temps down to MINUS 49F and up to 185F. I did not even know they existed until now. I am ordering eight on payday from Canada.
G Henrickson oh no... please verify this...
LiFePO4 cells are seriously damaged if charged below 32F, 0C...
@@SuperVstech Please check his Comment again, hes talking about LiFeYPO4, not LiFePO4 :)
xxcr4ckzzxx agreed... however, I can find no evidence that the low temp charging abilities are different from non yittrium cells...
@@SuperVstech Haven't looked that up, but I wouldn't think it either.
Great Video! I´m searching for a 2kw powerwall system that could supply my house. But the monetary return it´s almost impossible with the prices in Europe. Solar panels aren´t expensive, but inverter + charge controller and batteries, are a lot of money. Thanks.
Is Grid-tie done in Europe? When the grid is down though... If you live on a hill, you could create a dual in-ground reservoir system! When excess power is available, pump water to the top reservoir. When you need it, run a hydro-turbine as the water dumps into the lower reservoir. Mechanical battery storage basically, but it would have its own costs associated with hyrdro and building large cisterns underground to prevent evaporation.
I saw a documentary on an island that wanted to go "green", decided to use windmills, but needed an energy storage solution. This is what they used. This is also used in Missouri U.S., near where I live. The Taum Sauk reservoir, built in the 60's, broke in 2005 but has since been repaired and has been working for over a decade now. (They overfilled it.)
Just have to flex on you, my scooter battery is a 16s 12p 60volt 35ah 18650 battery which is a bit over 2kw
@@mashedpotatoes5323 That is a hell of a scooter! 7.5 megajoules! I need a wall that's 1.21 gigawatts, about 500-1000 of Great Scotts wall capacity. 1,210,000kw.
@@Reach3DPrinters i use grid-tie. But i´m only at home around 7PM. Your hydraulic solution its interesting. I need to learn about it.
@@mashedpotatoes5323 humm. Need to search old scooters...
You can exercise the lead acid battery and bring its "endurance", capacity back, through discharging the battery till it's dead, and recharging the battery multiple times. Great Scott, I'm sure you know this, I'm just bringing it up for those who don't, I like my batteries to last over a decade, I hate paying to replace them. Battery maintence is something that I don't think people are aware of.
I made a BMS with a TI BQ-IC and some extra components for about 60$ - plus board. From Texas there is BQ Studio with which you can easily set everything up.
7:33 - „bomb has been planted“
😂😂😂
cycle live is wayyyy better than tesla. Up to 30000 and liio only 1000
edit: the above is wrong! I confused lithium ion phosphate (the one in the video) with lithium titanate.
lithium titanate has very long cycle live (up to 30000 until the capacity goes under 80%).
lithium ion phosphate is still longer lived than classic liion but only up to 3000 cycles.
that is just wrong.
That's a good point, the cost of these batteries are crazy but as long as they live for 10+ years it's very much worth the extra cost over cheaper batteries as they'll pay for themselves eventually, although counter point is that you can get a bunch of 18650s in the 2-2.6Ah range from things like laptop packs for as low as $1 per cell and if you charge them to about 4v you do lose around 25% capacity but get up to 4000 cycles or more if you don't do deep discharges on them, so if you can keep costs down it may be worth the extra work to put a pack of them together instead, it'd certainly be easier to justify spending $150 upfront for a similar capacity rather than $500 on top of a slightly more expensive BMS.
@@SupremeRuleroftheWorld yes sorry you are correct. I edited my comment accordingly.
@@vgamesx1true, that was what I thought. but I mixed up the battery types a little bit. I edited my comment accordingly. please have a look, I dont want to spread wrong information.
Awesome project! I really enjoy it.
Nice system. I love messing around with prismatic lithium cells. I find that those particular cells like an absorption closer to 3.5 volts/cell for prolonged lifespan
- 20° in deutschland? Auf der zugspitze aber ich denke nicht das du da oben wohnst
Jan498 Maybe Sleswig in winter near sea level?
@@johnfrancisdoe1563 well i know that in Summer it is 2° on the zugspitze
-20 gibt es immer wieder mal, letzten Winter waren es sicherlich auch 15 tage und da nur auf 600-900m Höhe. Das ist noch nichtmal in den Alpen sondern weit davor.
9:42 those SPEAKER CABLES are not up to code and WILL burn like a candle wick
How do you know they are speaker wires? When I went to Germany a few years ago I saw all manner of DC wires and they did NOT look like what we have in America. Appearance is not everything.
@@geraldhenrickson7472 Because they're clearly jacketed in PVC, which catches fire.
You need wires with FT4 or FT6 jackets to pass them inside a wall (e.g. ethernet cables, in-wall speaker cables, telecom cables, etc)
Although the pack does look like a bomb it's nice. Great job.
Great Scott !! Great explained Great Video!!!
134 pcs Samsung INR 18650 25R = 335 euro at nkon.nl ..just sayin..
134 pipe bombs..
His Wh/$ calculation for the Li Ion battery is wrong. He showed 3,35€ for a 25R cell (3,6V*2500mAh= 9Wh) making it 2,7 Wh/€, that's the same as his bigger LiFe battery.
Also, the LG INR18650-M29 2850mAh is 2.17€ for orders between 100-199
Wrong Chemistry... However 128 LiFePo4 6Ah cells (OYE 32700 on Aliexpress) cost about 560€ shipped to Germany. With a 2nd BMS to manage 4 cells in parallel on 32 channels, and 200€ for connection material, we get a complete battery system with 2400Wh for 1200€ or 2Wh/€ (spot welder not included)
500 EUR to run some lights in the garage. 14 EUR for a 50m power cord to the house... Ha!
The intro is so fire.
Great video as always
Stop overhighliting >
its painful to watch :/
Great job, something like this would of taken me a long time to finish. I don't know how to complete these projects in a week.
Thanks for sharing all your knowledge in your brain database :)
Not sure about in Germany, but in the US your best bang per buck are golf cart batteries. Cheap, lots of deep cycle power, and they last 8+ years if you take good care of them. Energy density, IMO, doesnt matter much for stationary solutions.
Thank you. I was thinking of making one 🔋🔌
Thanks! Extremely interesting and informative.
Very interesting solution!
Guter Wortschatz - schöner Film!
klasse video, klasse projekt. Bleibt am ball!
Love your videos. So educational and....I'm kinda hooked on your intro music ;-)
LiFePo4 FOR THE WAY!
Great choice!
This is far better than most "DIY powerwalls" which are badly wired death traps of almost dead 18650 cells.