Help cell level fuse calculation

[Lady V]

Howdy,

I’m building a 4s40p (12v 100Ah) battery using a123 26650 cells.

I originally wanted to use the round fuses from battery hookup but they are for 18650 cells. I like how it disconnects rogue cells.

::thinking out loud:::

I did look into nickel strips but I’m unsure how they disconnect rogue cells... ? then again I do need them to connect the cells too?

I just can’t wrap my mind around how to size the actual cell level fusing using resister legs. And if I used resistor legs then I need a bus bar...what size copper would I need?

This is really the only step that is blocking me from building my system ?

Is there a formula or chart to find out this out? Do I need to calculate it based on the cell, the wire, or both?

Thanks in advance!

 

[snoobler]

If those are Lithium NMC (3.6-3.7V nominal), 4S is a crappy choice for 12V. The chemistry just stinks for that. If they're LFP, no fusing needed.

Check out this guy's builds:

HBPowerwall

Creating a Tesla-inspired Powerwall using 4480 18650 Cells from used laptop batteries. Check out our community @ www.diypowerwalls.com (forum) or www.faceboo...

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