Sizing Nickel Strip for Balance Leads?

[YoshiMoshi]

How do I size nickel Strip for my balance leads in a power tool battery pack? Should I just take the maximum charging current of my cells, multiply it by the number of cells, and there I go?

I'm a 5S3P configuration each balance leaf is connected to six cells, the parallel joint connecting one parallel pack to another, so multiply by 6 or by 3?

 

[docw009]

Do tool batteries charge thru their balance leads?

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[YoshiMoshi]

Do tool batteries charge thru their balance leads?

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Yes, I believe so.

 

[amberwolf]

Depends on the tool battery. Some don't have balance leads wired out to the charger (just a main + and -, and some form of ID pin, temperature monitoring, or communications pin).

You'd have to check the actual connector wiring for the specific toolpack to find out.

If the toolpack has an internal BMS, it's likely that it works the same way most others do, where it only monitors the cells via the "balance" leads, and *might* have a passive balancing function in the BMS where it drains down cells that overcharge.

I'd be surprised if it has any form of active balancing, or actually charges via the sense/balance connections between cells.


If you are not talking about a toolpack, but instead an EV battery pack built out of cells *from* a toolpack, then nothing about the charging of toolpacks themselves is relevant, and we would need to know the specifics of how *you* are building *your* pack as well as how *you* intend to charge and balance it, to give you relevant advice.