High-Power 4S 150A LiFePO4 Battery Pack – Advice on Connecting the Cells

[pumba990]

Hi everyone,

I am trying to build a high-output power 4S battery pack using Lithium Werks 26650 cells. These cells are rated for 150A for 10 seconds, and I want to connect them in a way that can comfortably handle this current.

People often use 0.1mm or 0.2mm nickel strips, but I don’t think that would be a good idea for this application. Even when stacking multiple strips, I am concerned that hot spots could form, potentially damaging the pack.

What would be the best way to connect these cells and handle 150A in a DIY project? Keep in mind that the use of exotic equipment is not an option.

Cheers

 

[PaulD]

I would check out the "copper nickel sandwich" thread. There are a number of ways to use the nickel to connect to the cells, and and then rely on copper to carry the current over the the next cell.

 

[bananu7]

For 150A per cell, i'm afraid it will be hard to avoid "exotic equipment". At the minimum, you'd need K-weld and a really good power for it to weld copper-nickel sandwich like Paul mentioned.

The only alternative option is soldering, either copper braid or straight wire. This is much more risky, though, as you need a very high power soldering iron and a lot of care. A TS100 could maybe handle it, but ideally you'd have 100-120W, proper tip and good temp cotrol.

Regardless of the method used, be prepared to scrap at least a couple cells for testing.