I need help building a battery

[RickAnstey]

I need help with building a battery

I'm thinking that there are experts on this forum who could help me (a novice) build a battery for my new Flux electric scooter. BTW, I now own my 2nd Model S; but that's another story.

Here's what I know about the battery requirements:
60V
26aH
scooter is: 1.56 Kwh
Physical dimensions of the space for the battery: 9 3/4" x 3" x 14"H

If you would like to help, please tell me what else you need to know. Thank you.

 

[rayan]

ust small tip: discharge cells before making or disassembling back. Trust me, it really helps with making progress safer. With brand new cells I would just go without touching them (nominal voltage).

When I build my first bigger battery back, I almost burned house down. Biggest issue in that back was insulation between series connection because whole body of cell is negative and positive is only small circle on top. It didn't have any other insulation than cell warps that were damaged. And they were all fully charged cells.

Now I do have a quite lot of experience in making batterybacks and also have been using insulation paper between series connections after that one particular pack.

 

[Valore]

Here's what I know about the battery requirements:
60V
26aH
scooter is: 1.56 Kwh
Physical dimensions of the space for the battery: 9 3/4" x 3" x 14"H

If you would like to help, please tell me what else you need to know. Thank you.

Are you sure you know what you are doing?
60V / 26Ah is a huge pack, 1.56kWh of energy.

If you want 60V nominal voltage, that's 17 cells in series. 26Ah will require 10 cells (for example 2600mAh Samsungs: Samsung ICR18650-26H - 2600mAh, 3,6V - 3,7V ungeschützt | akkuteile.de) in parallel.

That's a 17S10P pack, 170 cells in total.
I would recommend buying or building a spot welder for this job, as you need to make 340 solid connections (plus and minus on 170 cells). Plus battery management wiring.

DIY Spot welder:

 

[Valore]

ust small tip: discharge cells before making or disassembling back. Trust me, it really helps with making progress safer. With brand new cells I would just go without touching them (nominal voltage).

When I build my first bigger battery back, I almost burned house down.

You don't need to discharge them.
You need to make sure that all cells have about the same voltage. Can be full, nominal voltage or empty, doesn't matter. But roughly the same voltage (+-0.05V).
Otherwise the higher voltage cell discharges rapidly into the lower voltage cells upon connecting and yeah, this can burn your house down.

I have some experience assembling larger Li-Ion packs for boats.