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IR and capacity variance in parallel groups


1 µW
Mar 8, 2024
Am planning to build a second 6s6p 25.2ah battery pack out of molicell p42a, I need help with the following questions
1. Ik that we have to match the cells based on their capacity and ir for grouping, but what's the allowed ir and capacity variance range ( in terms of percentage) for cells in a same parallel group and between different parallel groups.
2. In the earlier pack I built, at the end of 4c continuous discharge rate from 24.9v to 19.1v, the pack temperature showed about 50-55°c and it takes like 30-40mins to cooldown to 45°c. Are these temperatures acceptable? Ambient temperature around 30-35°c
3. I don't have any onboard BMS, so at what ∆v should I consider to balance charge my pack ( 15-30-40mv )? Usually the variation in my pack is about 30-40mv.
4. To increase the cycle life, is there any stop charge and discharge voltage range to follow while not giving up on the capacity. Can't reduce the continuous discharge rate.

P.s : thanks for the reply mate.