How many nickel strips I need for my 10s 3p?

Ok, I’m making a 10s 3p. My strips is 0.12mm thick and 8mm wide. I have 30 Molicel 2600mah 35a. Once I connect everything. It should be 7800mah 105a. Now how many strips I need for this layout(this is a flat battery layout)? I want to make sure it doesn’t catch on fire down the road.

I have two motors that draws 52.5a each if you want to know.


I just can’t find the current rating for this strips. Second, I don’t know the math for this.

Alright, a couple things:
Using a nickel strip like shown in either of these photos

is not a good idea. Even with a very stiff deck, the battery can flex enough to cause the nickel strip to fail, either at the bend (in the case of the upper photo) or at the welds (in the case of the lower one).

Using nickel strip for series connections like this if generally fine for brick-style batteries where flexion is nonexistant, but for flat batteries it’s not a good idea at all.

You should use flexible, high-strand-count copper wire for all series connections, including the ones in the middle there where you show nickel in this photo.

As for current ratings and ampacity, here’s a bunch of info.

Check the Battery Builders’ Club thread for more tips and tricks, and pictures of batteries built using these best-practice methods.


mAh is milli·amp·hour

mah is milli·atto·hour

A is amps

That .12x8mm can safely conduct about 8A, as everything is attached right now the pack can safely do about 8A total.

So I suggest you A: solder the packs together using silicone insulated stranded copper cable and understand you can pull a max of 10 battery amps, or B: you could deconstruct, replace thin nickel strips with large cut .2mm nickel sheet that can safely and coolly conduct more current.

@MysticalDork already touched on the flex portion.

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I hate to pile on top of everything else you’re being told but the Molicel P26A will perform terribly at 35A and you will shorten its overall life (its “cycle life”) a lot running them that hard.

An occasional burst to 35A (each) won’t speed up the aging of those cells too much but you need some serious, very serious, connections for each cell and the pack to handle even bursts at current levels that high. You’ll get a lot of voltage sag too.

If you were only referring to theoretical ratings, and were not going to use them anywhere near that hard, then…umm…never mind. :slightly_smiling_face:

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My pack just caught on fire cause I didn’t use enough nickel. Fwiw.


Sorry that happened and hopefully it wasn’t too bad. Any chance you could share some pics of what caused it?

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Ok guys… Im going to start over again. I’m going to use 10awg wire for the series connection and 0.20mm 10mm wide for the parallel connection. This battery stuff is madd annoying to get

I’d actually suggest three times 16AWG over one times 10AWG

Pulling the current out of the nickel in multiple places causes less heating, and also the smaller wires are more flexible and easier to work with and to solder.


Also 10awg is big and bulky.

Realistically, a 10s3p p26 will sag so much if you draw 35 amps per crll, I’d only draw like 25 at most. With 25 at most, dual 12awg, triple 16awg would be good.


I thinking of doing this layout with the 10awg wire. You think this will create heat as well?

Also the problem with single 10awg is there’s no redundancy if something breaks.

That layout is also more dangerous because if the cells were to touch in the middle it would be a short.

If you do the other layout then the middles are connected together anyway.

To be fair, it is not very hard to insulate the middle well. Fiberboard and tape will make it nearly impossible to short

The other layout is a huge pain in the ass IMO

OP, I also recommend multiple wires instead of 10awg. 10AWG is super annoying to solder onto nickel with a cell heatsink too. 2x12 awg or 3x 16 are good options.


Can confirm. U shape is far easier than stupid squiggly shape and insulating the middle isn’t hard. Or you can turn the cells around the other way, like this…

Thats a 10s3p p42a


That pack is trash! Where are the overlapping balance wires? Where the cold solder joints? Complete trash.

On another note, beautiful as always brotha


the way I make packs I’d use 21, with one of them just being a skinny tab and the rest folding over the top