What is "balance capacity" in JDB BMSs?

[jbatx]

The JBD BMSs have value called "balance capacity". This value can be pulled off the device using the Arduino lib. I have three JBD (Overkill) bms's on three batteries and the values I get from them are

"45" from both 100ah batteries using 16S 100amp 48v units
"120" from the 230ah battery using a 16S 100amp 48v unit

The Overkill arduino lib README has only this to say about this parameter "Balance capacity in amp-hours". ...OK, but what does that actually mean and how is it calculated?

I don't really understand what this value represents. Anyone?


For reference, the cell voltage delta is 4mv and 7mv for the two 100ah batteries and 12mv for the 230ah. Current SOC is is 46% for both 100ah batteries and 53% for the 230ah.

 

[jbatx]

....I just realized what it means.

rate capacity * soc% = balance capacity

 

[John Frum]

I'm not sure what JBD or the author of the library mean, but if I said it I would be referring to the current in milli-amps that the bms could draw from a cell in order to balance it.

 

[jbatx]

I'm not sure what JBD or the author of the library mean, but if I said it I would be referring to the current in milli-amps that the bms could draw from a cell in order to balance it.

that was my first thought too. But, since the readme says it's in ah, that clued me into the calculation I commented above. I mean... I know there more to it - like coulomb counting, etc. But, at least now I think I know what it is