Hi , I'm Sara Hejazy a software engineer, I can try help out with your equation, no promises do you have any supporting documents I could try to estimate the equations from? all I know it that WH = V * AH and that calculates the capacity of the battery , theoretically the battery should have a stable voltage of 12.6V to be given to the load for the est imitated hours, it's the current that changes/ drain according to the load until the battery is fully drained
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