The Real DIY FAKE Powerwall

josephchrzempiec

josephchrzempiec

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Jul 4, 2017
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Hello Everyone i would like to apologize ahead of time for any wording that is not correct or out of place. I'm not good at writing in forums or in paper. I'm more of a hands on guy and talking in personSense this is my first Post in here. I have read many other post and comments and i must say people are coming up with some awesome ways to give back to the world. As they sayknowledge is power. Well I say what i learn in here I'm ready to Create my "Power"wall. So my first step is what Cells should i use? For me it was real easy to decide. So i decided to use Fake Cells as most people call them. Well they are real cells But what makes them not What they say they are is the fact they are low capacity cells they stated they are 9800mah cells. But in fact they are only 400mah to 550mah. I never paid for they battery cells they was giving to me from a friend of me. They first 800 of them. They i thought i can do something with theses. I don't mean to Power up a whole house on them. But to at least get some Lights going two of three of them.


Below is a image of these cells. What i forgot to say above is that the first 800 cells was giving to me i did pay for more of them i have a total of 6500 of them. A friend of mine bought them because he thought they was a great price online and found them on aliexpress. My friend rebuilds Army flash lights and resells them. But when he got them in and tested them. They didn't last no more then 5 to 6 minutes in the flash lights.


Okay so now down to business. I did buy the rest and i know I'm crazy for doing it. But that's all on me. I have tested these cells and made 12v packs out of them with a 1000w pure sine wave inverter i have tested out a space heater and they cells didn't explode LOL So i decided to make my Powerwall project out of them.


Here is a image of the battery cell.


image_lbnlda.jpg



So my next thing is What side of a pack would i need or would like even love to make. On that note i have thought about it and went with a 148p3s setup. The reason for this is because my inveter even though it is only a 12v inverter when i try to apply a 4s pack the fueses on the inverter popped. i thought i could setup 16v for the inverter but in fact i was wrong. 15v is the max anymore then that it blow the fuses. So that set my pack for a 3s setup.

The reason why i went with a 148p3s is because This is a DIY version of a Tesla Powerwall. So i looked at what Tesla had in there powerwalls and they have two 444cells pack in there Powerwall. Now if you take 444 cells and divide that by three which comes out to be 148 cells that was a Perfect match to what i was trying to do. So with outrealizing it i was making a Tesla Power module. So next step is how so i put these cells together. Well That is for Step two of this project. This is Step one.
 
Do they test OK? Like not getting hot ect ect. Given such a low capacity, I would cycle several of them over many times to see if they are going to retain that capacity. Also check for self discharge.

Most of us would consider it not worthwhile to assemble a power wall with such small cells. But if you have the time, why not? Its not like you had to spend hours tearing down laptop packs to get at them.

The only thing I would want to know, is will those cells still hold up after a large number of cycles? Id even look in the cell database and see if I could narrow down a look at the original manufacture.

All that said, I can see your point that's 3250ah in cells. I would surely consider using them. I am going to use a batch of 600+ Sanyo 'heaters' to build some packs. Just make sure I have enough temperature monitoring.
 
The reason why I'm using this and not my Laptop cell packs is not because I'm lazy it is in fact that no one else would use them. The whole point to me of a DIY Powerwall is to use what you have correct. That being tearing out some battery cells from laptop packs or Having some cells that no one else would like or use. even the charge controller and inverter. If you have it use it right, Ant that what this is all about?
 
Reply written before OP eddied a post:

If you will have no active cooling on your power wall then you must test your cells without active cooling. Also, while they may not get hot on discharge they may get hot on charge. There is no substitute for testing each cell individually. There is a real potential danger of a hot cell being lost among its neighbors in a large pack, you may never see it.

That load is huge, and a big ask for cells that only test 500mah. That's 83a at 12v, or 2.7a per cell. Ok for a test, but defiantly in service, keep the load per cell as low as possible in order to prolong what little life those cells have left.

I will be following this project closely. It does appeal to my interest how well low capacity cells will work in the long run.

I do indeed see the point of this project. The only thing that worries me about low capacity cells is that they (i assume) are pretty close to failure. Therefore for all your effort of assembling packs, they may not last long.

However, I once again plan on using more or less every cell I can. Making my system modular, so as cells die, or I acquire better cells I can swap out the lesser cells. It also will help isolate faults, if I know a given number of packs have 'bad' cells I can simply disconnect the offending packs, and examine them, with little or no downtime.
 
At all times charging and discharging these cells i did have fans on them running. I never charge or discharge them without fans on them. Even when i did my test i have fans on them. My next step is to test without fans on them. I will test this in a few days. But you are right i have heard they do get warm not hot but warm when charging and discharging. That is the reason why i put the fans on them for this reason. Geek said:
Well that would be the case. If you will have no active cooling on your power wall then you must test your cells without active cooling. Also, while they may not get hot on discharge they may get hot on charge. There is no substitute for testing each cell individually. There is a real potential danger of a hot cell being lost among its neighbors in a large pack, you may never see it.

That load is huge, and a big ask for cells that only test 500mah. That's 83a at 12v, or 2.7a per cell. Ok for a test, but defiantly in service, keep the load per cell as low as possible in order to prolong what little life those cells have left.

I will be following this project closely. It does appeal to my interest how well low capacity cells will work in the long run.
Click to expand...

At all times charging and discharging these cells i did have fans on them running. I never charge or discharge them without fans on them. Even when i did my test i have fans on them. My next step is to test without fans on them. I will test this in a few days. But you are right i have heard they do get warm not hot but warm when charging and discharging. That is the reason why i put the fans on them for this reason. Geek said:
Well that would be the case. If you will have no active cooling on your power wall then you must test your cells without active cooling. Also, while they may not get hot on discharge they may get hot on charge. There is no substitute for testing each cell individually. There is a real potential danger of a hot cell being lost among its neighbors in a large pack, you may never see it.

That load is huge, and a big ask for cells that only test 500mah. That's 83a at 12v, or 2.7a per cell. Ok for a test, but defiantly in service, keep the load per cell as low as possible in order to prolong what little life those cells have left.

I will be following this project closely. It does appeal to my interest how well low capacity cells will work in the long run.
Click to expand...
 
Okay here is the Second part of my Real fake DIY powerwall. So what i have been thinking about is the cell holders. Keith from the Diy forums and Facebook forums I have bought Cell holders from is a awesome dude. If anyone in the USA needs cell holders 4x5 or 1x3 cell holders he's the man that can hook you up.

So back to what layout of cell holders i would need to get my 444 cells. Well i forgot why kind of cell holders would i need. I went with a 4x5 cell holder for a few reasons compare to 1x3 cell holder. The first reason is i they can hold and handle a lot more cells. The second reason is i have enough space in my rack to hold a 40x16 Cell holder grid. This in return gives me a total of 640 spaces to hold cells. But sense I only have 444 cells What do i do with the rest of the blank spaces of cell holders. Well What i did was sense they are in 3 groups of 148 cells i have a top left layer and a bottom left layer i spaced out a few holders to get a whole right side for the last third 148 cells remaining.


Below is a image of how I'm going to place my cells. Now mind everyone if you have OCD or just being normal they this will freak you out LOL

image_rgoqwi.jpg



image_oitjpr.jpg



So this is my prototype of my first pack. I forgot one thing i did take off one layer of 4x5 cells. So now it is a 35x16 Grid. But if you notice there are to the left blank spaces I left them alone for right now. Something will be added soon. Not sure how I'm going to add it but you will be surprised :)


So in part three i would like to talk about what Charge controller i went with and DC disconnects for the panels. I hope everyone who is reading this. Enjoys it as much as i do. Staytune....
 
2.7A load per cell that is massive load on those cells :D They wont last long on that load. I would say they should not be loaded more than 0.5A to last. And the fact that they dont have much capacity is another thing
Neither less as you said. Use what you got. Hopfully you got the time for it :)
 
Hello thank you for the comment. Yes they don\ said:
2.7A load per cell that is massive load on those cells :D They wont last long on that load. I would say they should not be loaded more than 0.5A to last. And the fact that they dont have much capacity is another thing
Neither less as you said. Use what you got. Hopfully you got the time for it :)
Click to expand...
 
josephchrzempiec said:
The reason why I'm using this and not my Laptop cell packs is not because I'm lazy it is in fact that no one else would use them. The whole point to me of a DIY Powerwall is to use what you have correct. That being tearing out some battery cells from laptop packs or Having some cells that no one else would like or use. even the charge controller and inverter. If you have it use it right, Ant that what this is all about?
Click to expand...

Can not agree with this statement anymore!

Use what you have, stop it from going straight to landfill - GIVE it a second life!

That said - Sounds like you're starting this project knowing what you have,so build to that & like Daniel said, "0.5amp" would my 'safe place' if not even lower load per cell.

You'll be doing a great thing for the community trying this sort of project even if it failscompletely I'd love you to follow through so the community as a whole can learn with you.

Pete
 
hbpowerwall
josephchrzempiec said:
The reason why I'm using this and not my Laptop cell packs is not because I'm lazy it is in fact that no one else would use them. The whole point to me of a DIY Powerwall is to use what you have correct. That being tearing out some battery cells from laptop packs or Having some cells that no one else would like or use. even the charge controller and inverter. If you have it use it right, Ant that what this is all about?
Click to expand...

Can not agree with this statement anymore!

Use what you have, stop it from going straight to landfill - GIVE it a second life!

That said - Sounds like you're starting this project knowing what you have,so build to that & like Daniel said, "0.5amp" would my 'safe place' if not even lower load per cell.

You'll be doing a great thing for the community trying this sort of project even if it failscompletely I'd love you to follow through so the community as a whole can learn with you.

Pete




Hey Pete you are right. I'm sorry let me rephrase that statement. In my case i use what i have and can get. The idea of reusing old cells is awesome and yes Giving them second life is a great thing. starting with laptop battery cells or even Acid batteries. I would of did that my self. however I couldn't for a few reasons. Which are personal to me.This iswhy my friend gave me 800 of his cells and i bought the rest with some money i have borrowed. In my case it was the best thing to do. Another reason is some people might get rid of these cells because there Low capacity cells and send themback to the owner or seller. So in this case i also gave them a second chance or as this case a second life chance. But Pete is right giving second chances to cells and creating something new from something old is why I love making this projects my self.
 
Just beware of that most of those cells are made "fake" in terms of quality. Not just the capacity but quality as such. Some can test 300 and some 500 and some 800. Some lasts 10 cycles some 100 cycles :) Just beware of that when you build.

How do you plan to get it together? Fuses on each cell?
 
daromer said:
Just beware of that most of those cells are made "fake" in terms of quality. Not just the capacity but quality as such. Some can test 300 and some 500 and some 800. Some lasts 10 cycles some 100 cycles :) Just beware of that when you build.

How do you plan to get it together? Fuses on each cell?
Click to expand...



Hello thank you for that information. I so far tested each cell charge 12 times each. Took me a while too. So far there holding up.
I will be doing a new test soon with no fans and see if they get warm or hot while charging them or discharging them in the Charger. As well as making the First pack of the Powerwall to see if they get warm while charging or putting a load on them. I will be using my 1250w inverter and putting a 100w light bulb on it to see.
 
Well, as Mythbusters says... there's no experiment failures, just data gathering or analysis failures... :)

Backblaze does something like this... they buy a *huge* quantity of hard drives, so they inventory and report out success/failure rates, about every 3months. The dataset is so huge, it would be a waste not to do it.

Sounds like an opportunity, measure how bad they are. To be honest, if you put that many "fake" cells in front of me, I'd be doing the same thing... have some fun, go big... then document it, once and for all, the good and the bad. If you're going to build packs with aged LG cells at 1000mAh, why not new 500mAh cells... just going to have a lot more work to do, regarding assembly.

Yet I'd follow a slight modified process...
* test each cell individually... every single one. charge, discharge, charge.
* at first build packs with cell holders, individually fused
* find an inverter that could handle 14.8v, or install a 12v regulator

When comfortable, then I'd probably build 4x10s packs... let's face it, you'll be splitting those packs, when cells start to fail.

Yet amazing job, wish I could help. :)
 
sbagdon said:
Well, as Mythbusters says... there's no experiment failures, just data gathering or analysis failures... :)

Backblaze does something like this... they buy a *huge* quantity of hard drives, so they inventory and report out success/failure rates, about every 3months. The dataset is so huge, it would be a waste not to do it.

Sounds like an opportunity, measure how bad they are. To be honest, if you put that many "fake" cells in front of me, I'd be doing the same thing... have some fun, go big... then document it, once and for all, the good and the bad. If you're going to build packs with aged LG cells at 1000mAh, why not new 500mAh cells... just going to have a lot more work to do, regarding assembly.

Yet I'd follow a slight modified process...
* test each cell individually... every single one. charge, discharge, charge.
* at first build packs with cell holders, individually fused
* find an inverter that could handle 14.8v, or install a 12v regulator

When comfortable, then I'd probably build 4x10s packs... let's face it, you'll be splitting those packs, when cells start to fail.

Yet amazing job, wish I could help. :)
Click to expand...



Hello Sbagdon

Yes that is what I'm all about is having fun, learning about all this Powerwall stuff. Keeping safe Showing people what i have done sharing what i have learned and in the process bring something cool to life. That's why I posted in this forum to share what i have learned. a lot of people say oh it is a waste of money and time because they are fake cells. I disagree with that because of the fact doesn't mean if i got the battery cells from old laptops batteries, cameras or even bought them from someone or somewhere the fact is to Share what i have learned about theses batteries. And to share my Powerwall project how i build it.


I have a new video coming up on youtube of my pack. Hope it will be a good one :)
 
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