Milwaukee m12 batteries contain samsung 20r 18650s!

Got curious at work and found that my Milwaukee tools have these cells the 240ah battery’s have 3 and the 400ah batteries have 6. You can buy sets of 2 of the 4.0 battery’s for 40 bucks on ebay! That’s around 4 bucks a cell or get used one’s cheaper! Are 20rs good for eboards? I want to build a 10s3p.

3 Likes

good to know, but it doesn’t look like much of a discount

they look like they would be ok with 22a discharge but i think 25r’s are the standard, or lg hg2 for more capacity.

With my math, these would cost $3.33 per cell if I bought the 4.0 packs new. I think they would work fine for a single drive 190k motor for transportation to work and back

true but i would always go for the higher capacity since its the same size/weight

are these cells tabbed? that would make it nice since you can solder on easily
I guess the bigger packs would be 3s2p, so why not do 12s2p or 9s4p.
with 9s4p you’d be around 10-12A/per max, so .5C, and a really nice 2-5A average…

Tabbed meaning spot welded in series already? Do you think a 10s3p would get me 4.5 miles to my work on a single drive? Couple up hills and down hils, I weight 150lbs

Or could a 10s3p do the job?

yes since raw cells need to be spot welded this could make a diy pack “easier”.

lets see. these cells are about 2ah. 3.7v, so 2*3.7 = 7.2whr/cell
7x 30 = 210whr.

I have about 250whr lipo and get 10-14miles on a single, same weight, you’ll be fine!

I say 9s, or 12s because they are already in 3s groups, so it would mean less tearing apart and rearranging.
they are 3 flat, and 3side/side, you could get a bit creative with placement and keep as many factory solder points as possible, exposing the cells to less heat…

3 of them are side by side but the other 3 are in the shape of a pyramid. Those would need to be released welded or soldered

thats what I mean about being creative, you could so something like this

unless you really want a flat enclosure I would work with what you have… 9s, 2p, the fatter side would be near the truck so you wouldn’t lose any clearance, and it would be narrower and more style! :sunglasses: