Korishan's Powerwall

Well, looks like I'm finaly gonna be able to create my own thread here

Ok, here's what I have so far. I don't have all my electronics in yet, but I did do a quick test on the cells voltage. Most cells were 1.8v and above. Several were 3.1v and up.

Here's some pics of the cells I've gotten. I'll do a lot more testing when I get the rest of my gear in.











The last set of cells to the right, 4 green and 2 blue, were at .99v or lower. So I decided to immediately segregate them at the get go.

So here's the break down of each type:

From left to right
Sony - US18650GR x8 Green
Sanyo - UR18650Y L47C x6 Red
Sony - US18650GR x4
Samsung - ICR18650-26FU x6 Pink
Sony - US18650GR x4 Green
- CGR18650 CE x6 Light Green
Samsung - ICR18650-22F x6 Teal
- CLICR18650 x4 Blue
- LGDP218650 x4 Dark Pink
- HJIFJT6 059345 x8 Red

So, watcha think?

Alrighty, here's the 220lb load. This is the first video. Well, my first video ever. Please be nice

You sir just got a new subscriber
everyone has had a first video, keep up the awesome work and keep us informed i'd love to see your progress.

I was wondering who the subscriber was

Thanks, I'll be doing the best at keeping the channel up-to-date.

Subbed - DON"T LET ME DOWN hahahah

LOL I will try not to disappoint. You, or anyone else. or even myself

Update!

Decided to start doing some of the brute force tonight. I think, afterwards, the brute work was done on my hands. That plastic is rough.

Came across several types of cells. Even have some Panasonic ones in there. No testing was done at this time, just breakdown.

I wondered what those were too.
I thought a fuse but still not sure

Smaller green ones - fusible resistors or solderable fuses (must read what's on them), bigger ones - thermal fuses.
Both are called "low level fire safety".

Ok, so I broke down that first box worth which I recorded the end result in my last video. Took me about 2hrs to strip 'em all. There's a little sticky stuff on some of them, not to bad on most. I decided not to worry about the 'all' the junk on the cells in case they turned out bad. Although, in hindsight, I guess I could do a quick voltage test as I'm breaking them down. Hrmm, for next time.

So, here's a couple of pictures of my progress. The 1st one is before I did a quick voltage check, the second one afterwards. In the second one you'll notice some of the cells are now in front of the packs. Those cells are cell that were below 1v. There were a few cells that tested between 1v and 1.5v, but at this point, I left them in the main stack because I don't have bins as of yet. (I really need to get those. Probably will tomorrow at wally-world or maybe check the fleamarket).

Now, I will have to say that I was happily surprised by the second half of the batches. The stack of dark pinkson the right, only 3 cells tested below 3v! And several were over 4v!!
Also, the darkblues on the left also tested 3.2+v. The greys also tested above 3v, and most of the greens right next to them. I'd say about 1/3 are >3.5v, 1/3 between 2v and 3v, and a 1/3 below 2v; of what is left behind the packs.

Later on I will do a proper test of the cells when I get my rig finished up because I want to do a voltage and resistance test at the same time.

It's good to see people making progress. What do you have planned for your measuring equipment?

I just checked a very much ad hoc 3s12p harvested pack I made up a while back to run a small inverter for lights while camping, after two years without even looking at it, it was still balanced within 30mV.

Someone here posted the idea of checking self discharge in the discharged state, I didn't mention it at the time but that sounds good to me. Every pack I've had trouble with due to the cells was due to self discharge either stronger or weaker, a dead short can be thought of as "extreme self discharge" from a certain point of view. Once you get enough cells in parallel that the other issues such as capacity and internal resistance sort of average out but still only one high self discharge cell can kill even a good sized pack.

Update:

I've been going slow at the charging procedure since I started with just 1 4056 hooked up. Now I have 4; I hope to add the rest by the end of the weekend. That'll give me 16 chargers.

Using the computer PS works like a charm. I'm using my multimeter to measure current draw and the max that 4 have drawn so far is about 3 amps. Maybe if I put in 4 <3V cells it might pull the full 4amps. I'm kind of just randomly dropping cells in.

At of that first batch of the large haul I received, here's the numbers:

Semi-Total of Box 1: ~223 (some were rusty, damaged during removal, damaged while removing silver strips) (also haven't finished breaking down the other packs on the shelf yet; doing one set at a time for the time being)

28: < 1V
11: 1 - 1.5V
19: 1.6 - 2V
25: 2.1 - 2.5V
49: 2.6 - 3V
55: 3.1 - 4V
8: > 4V


The rest have already been charged to 4.2V, but they were taken from the groups that were >3V

I did have 2 Reds get hot during charging. They got up to 3.9V and then started getting hot (almost too hot to touch) and just stayed there. I've set them to the side and may try again later after they've rested. I'll also check they resistance of those cells and othersthat are "odd" (which, there was another one that kept making the 4056 flash; bouncing up/down voltage just enough to trigger on/off of the charger, also set aside).

I was going to have pics, but my phone died as I was taking them Will try again tomorrow. Maybe even a short video update as well, we'll see.

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Elmo said:

...What do you have planned for your measuring equipment?

Click to expand...

Are you referring to charging/dischargingcapacity checking/recharging?

What I plan on doing is setting up a rig to capacity check and also do resistance checking periodically. I'd like to incorporate the charging modules in with it so that resistance can be checked during charge/discharge/recharge.
I have it in my head how I'd like to set it up, but putting it down on paper/pcb-draw/words is kind of hard to do for me.

But, essentially I'd like to have 1 arduino, multiple tp4506's for charging and since resistance checking only takes a couple seconds, I'd only need 1 set of loads/resister to do the checking. That is, for a certain bank of testers. I know that after a point, I'd have to add a second set of load/resisters. I haven't figured out the number ratio for it yet.

Pack design is still up in the air right now, too. I want it to be modular to a point. Well, maybe not so much as "modular", but "plug-n-play". I want to be able to pull a pack out to service it without having to bring the whole system down for the disconnect. I'm thinking of using XT60 or XT90's for the connections and have them firmly held down so when I plug or unplug a pack, the ends stay where they are supposed to. I might go with the anderson plug since it's specificallydesigned for that. But, will see when I get to that point.

Korishan said:

Using the computer PS works like a charm. I'm using my multimeter to measure current draw and the max that 4 have drawn so far is about 3 amps. Maybe if I put in 4 <3V cells it might pull the full 4amps. I'm kind of just randomly dropping cells in.

Click to expand...

When you're measuring make sure all of your tp4056 in CC (constant current mode, stage1 on the pix).
Then it should be near to 4A.

Korishan said:

I did have 2 Reds get hot during charging. They got up to 3.9V and then started getting hot (almost too hot to touch) and just stayed there. I've set them to the side and may try again later after they've rested.

Click to expand...

Usually these cells has big internal resistance. IMO not worth the risk.. put aside and it'll be good for some side project. Anyway don't forget to check your tp4056 modules too because i got a few with really high >4.2V charging voltage.. and i got some warm cells too.

FERCSA said:

Usually these cells has big internal resistance. IMO not worth the risk.. put aside and it'll be good for some side project. Anyway don't forget to check your tp4056 modules too because i got a few with really high >4.2V charging voltage.. and i got some warm cells too.

Click to expand...

When the 4056's turn blue, I'll check the voltages of the cells while still plugged in. So far, the highest I've seen is about 4.18V. I'm not there when turn blue to see if they are in fact shutting off at 4.2V. I pulled some off today and a couple cells were 4.1V. So I don't know if they were just short charged, or they self discharged that fast in a few hours.

After they've set for a few days and I do a recheck, then I'll know better if those cells are self-discharging that fast.


I really need to get off my lazy bum and get the rest of the chargers set up to I can get busy on cell charging

Ok, here's the pics of the cells in their bins. I need to get some more so I can do better sorting. But I figured that break down of .5v per bin for anything lower than 3V would be a good start. Pretty much anything over 3V would be good cells (unless it's like the couple reds that got hot charging even though they were over 3V during testing)

I've been monitoring the voltages of the TP4056's while charging. I watched one cell bounce around 4.2 and 4.21 for awhile, about 10 minutes or so. but when I pulled the cell out and tested it, it was below 4.2v, closer to 4.15V or so. Several cells were like this.

Sooo, if we build a monitoring, we may need to tap into the TP4056 differently to get the charge voltage. Unless there's a way to momentarily "pause" the charge and check the state. but if you pull the cell out at that time and try to reinsert, the TP says it's charged enough and won't continue charging.

Hrmm..... :idea: :idea: :idea:

In response to my last post, I think I figured out the voltage thing with the TP4056's. It's kinda like your car battery/alternator. While charging, the alternator will put out higher voltage than the battery actually is going to be at when finished charging.

So, in this case, since when they are getting close to full charge, they are in CV mode. This makes since now that I really think about it that the 4056 reading was at 4.20-4.21V and still charging. When I pulled a cell out "early" and checked the voltage, it was at 4.03V (or close to that). So they aren't mis-reading or anything like that.

Figured I'd add that addendum before I went on to the next portion of this post

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Ok, here's anupdate I'm sure everyone has been waiting for in antsy anticipation

Well, not quite there is a small update....

I'm about through with my first box of cells. There's about 200 good cells out of about 223 total cells for that box. That's a pretty good average imho altho, will have to see what the rest of the boxes churn out; so no outrageous hooplahing just yet.

And here's the video link. Please excuse the shaking, jittering, stumbling, forgetful ninny behind the camera

Yes to have a current flow when there is resistance the voltage need to be different on both ends or else nothing will happen kind of If you want a tiny bit lower diff that you had there then go for thicker wires and better contacts against the batteries. The last pieces is the Ir and that you cannot do much about.


Unless you did measure at the battery poles that is.

Quick update....

I've broken down some more laptop packs and got the results below. Right now, oddly enough, they come do right about 100 cells. I had a few cells that were bad straight from the packs as they had rusted ends, or were blistered with rust. Cells that have that kind of damage get binned w/o question. I don't trust those. Now, if a cell has some rust spots on the ends where the tabbing is, but it's almost like a dust, then I'll consider it.

The two pics do over lap by about a third. A good marker is that piece of plastic on the floor I was originally going to try to do a panoramic view, but didn't turn out right.









I got in my 2nd load of parts. So now I have a bunch of 4x plastic holders, 3 more Arduino Nano's, some headers, and a new oled screen. So I'll be able to start working on my next sub-project for the build.
I also have another project that will go along with this that I'll document and post when finished. It'll help speed upharvesting a LOT I'll keep ya posted.