How is .5c calculated?

[JonathanW]

On a 16s battery that is 280ah is charging at 140a .5c or is it 140/16? 8.75a .03C? Thanks!

 

[wattmatters]

0.5 C is the discharge rate which would drain the battery in 2 hours. If the battery is 280 Ah, then you would expect 0.5 C to be ~140 A.

BU-402: What Is C-rate?

BU meta description needed...

batteryuniversity.com

 

[JonathanW]

What if it was only a 12v battery with 4 cells. Its still .5c? Intuitively it would seem to be measured per cell no?

 

[Mattb4]

C = battery amp-hour rating.
So if you put a number like .5 in front of C it is algebra. Multiply.

Whether 2 cells in parallel, where total C doubles, or 2 cells in series, where C stays the same. It is still battery amp hours.

 

[DIYrich]

On a 16s battery that is 280ah is charging at 140a .5c or is it 140/16? 8.75a .03C? Thanks!

280ah is per cell. If they are wired in parallel, then amps stay the same, but voltage is increased.
Wired in parallel, when charging, each cell is getting the same amps, just different voltage.

 

[Lt.Dan]

280ah is per cell. If they are wired in parallel, then amps stay the same, but voltage is increased.

Wired in Series, not parallel.

 

[JonathanW]

C = battery amp-hour rating.
So if you put a number like .5 in front of C it is algebra. Multiply.

Whether 2 cells in parallel, where total C doubles, or 2 cells in series, where C stays the same. It is still battery amp hours.

This clicked for me thank you.