C rate for an ah/capacity check

[OTRwSolar]

How high of a C discharge rate should a healthy, well-balanced lifepo4 cell pack be able to support and still produce its rated ah capacity?

We have a 4s 200ah pack that produced 198ah with a constant .55c load (110a for 108 min). Is 198ah at .55c good, bad or indifferent? The pack was top-balanced prior to the test. Delta was approx. 200mv at low-voltage cut-off (2.700v). We frequently do high c discharges---should we bottom balance instead?

 

[Rednecktek]

Actually that looks pretty good. Industry standard testing is done at .2c and I bet if you re-ran the test you'd see the full 200ah.

 

[upnorthandpersonal]

Test conditions are usually at 0.2C, 25C ambient temperature. You're good!

 

[OTRwSolar]

Thanks for the replies. Good to know these cells appear to be in good shape.

Since we do a lot of high c discharges (.55c), gave some thought to doing a bottom balance. I assume a bottom-balance would probably move the large 200mv delta we're experiencing at low-voltage cut-off (discharging at .55c) to the high-voltage cut-off while charging? The end result no gain in ah output?