Panosonic 25ah Prismatic cells for sale $28

[Joachim]

[eric1565]

Update on the 12V car battery.

These cells do not take much to squash them down. All these bolt as hand tight. I have used the original bus bars as gages to make sure they are all good.

Still need to trim the all threads, and to put in a bottom supporting structure.

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[dafex]

Hi Eric,

why you didn't reuse the original brackets? Cut the brackets apart and weld them together to fit the length of the new batterie.

I have done this with 12s batteries to build 14s batteries.

Old and new Batterie

During disassembling

Welded brackets

[eric1565]

I thought about that, but I was in a hurry to make this. Also didn't have easy access to a welder I still have the brackets, and can still do that. But what I am currently doing is planning on making custom aluminum cases to hold the batteries.

The other reason why I didn't do it was because I still was not sure what size I needed it to be. Now that I have built up this 4S2P battery I know what it needs to be. I've now cad'ed it all up and have exact sizes.

Eric

[parabellum]

Hi Eric.

1.13"/cell looks right, where array starts to hold in 1 peace without cells sliding on each other, thanks.

Can you suggest a charge rate and max. charge rate for those cells?

P.S. I think it will not harm to add all new findings in the first post, like compression width, DCR and all relevant to the buyer information.

[eric1565]

Charge rate of .3C to 1C. I have not check to see what the cmax regens at.

The 3.3kwh charger charges at .3C

I know for Tesla cells we recommend .3C charge rate and these can handle much more.

I will update the first post shortly

Eric

[eric1565]

I gave a friend of mine the 12V pack I made. He has a 2500 watt audio system in his car. He had 2 car lead batteries in his car, and when he turned it up the voltage sagged to 11.2V. He added the lithium battery, and the voltage dropped to 13.2 when he turned it up. So significant improvement. He has yes to remove the 2nd lead battery to give me data on that.

I'm in the process of making an enclosure for the battery, and well sell 50, 75, and 100 ah "12v" batteries. They would run a bit better if the voltage on the alternator was increased up to 15V or so. The batteries will also have a 4S BMS installed.

Eric

[eric1565]

I got the 12V car audio battery together. I put in plastic spacers between all the aluminum parts.

I ran out of aluminum bar stock so I used some of the OEM buss bars.

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[parabellum]

That looks really cool. Nice CNC.
Why are you using aluminium for connectors?
My first thought was copper, I used it finally as well with some contact grease on (aluminium will need some oxide breaking compound to).

[eric1565]

I guess I can get copper. Aluminum is easy to get. And has decent current carrying capabilities.

Was thinking of making a nickle solution to coat the aluminum with... If going to do that I guess I should just use copper.

I was a bit worried about the oxide, but they use aluminum for wires, well for a while untill houses started to burn down. But that was a function of creep. Not an issue with bars.

Still perfecting the design. I will look into copper.

If u have any other suggestions or questions let me know

Eric

[999zip999]

Can you put a lighter or a ruler in those pictures so we can get a idea what size these packs are ? Thank you

[eric1565]

Here are some pics of the model.

I'm sorry they are not of the real part, but i'm lazy

You can hand calc it out pretty easy. Each cell is 1.13 thick, so if you add up the cells X 1.13 and then add on .375" for the 2 end pieces * 2 (.75" total) you should get the lenght of the pack. Yeah pretty close... calc says 9.79, actual is 9.7ish.

Weight is about 13 lbs.(about 1.6 lbs per cell) you can hold with one hand no problem... about 800Wh (each cell is like 93wh, I rounded) I can do any size up to 3 or 4' long. 10" is the longest so far, and I am sure there is a learning process for the longer ones... 20" is no problem, but I would guess longer than that gets to be trickly to assemble.

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[999zip999]

Thanks for the answer I will mock something up to check fit.

[eric1565]

Pic of the prototype with the 3D printed terminal caps.

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[999zip999]

That looks much better than the illustration

[eric1565]

Ok, still working on the car audio battery. But it could be anything depending on how the cell layout. This is a 100ah battery I am making for a guy. I am redesigning it to be beefier, because I think it is a bit wimpy.

Eric

[KD5ZXG]

So, how many would I need to buy from you to get them in an original frame?
I'm not even sure how many different sized frames you might have collected.

I'm on the north side of Dallas. How best might they get here from Houston
without the delivery man setting himself on fire? Even Greyhound won't ship
Lithium.

[eric1565]

I don't fully understand the question so here are multiple answers
1. In the stock OEM frame there are 21 - this is the cheapest way to get cells. U buy 21 and I'll sell them for $410 plus shipping
2. I can make any size frame any voltage any capacity range. The frames COST me about $100 to make so I sell them for $125. If I can lower that cost over time prices will reflect that. I would not do more that 16-20 cells... It started to be difficult to compress.
3. I have 2 assys for sale on eBay. Prices on ES are 10% less. I have a 50 ah and a 100ah.

I am scrapping all the current frames due to lack or size. I am beefing them up. Current end plates bend slightly, new style will not bend.

[coleasterling]

You clearly have CNC capability of some sort, but if you wanted to have someone else do it, I own and run a full CNC shop in College Station and would be interested in quoting your parts. I like your solution for these cells, overall. Looked at using them several times myself, but the form factor isn't quite right for my application.

[81forest]

Pm sent, are these still available?

[marty3d]

Are any of these still available?