My customer has a BMV712 with 2x 12V 200Ah Gel Batteries in parallel and there is a discrepancy between the SoC reading and the Ah Consumed. His load is a DC fridge that draws 7A when the compressor is running.
For example, SoC = 91.6% with 19.9Ah Consumed.
This means that there is 380.1Ah remaining. Total capacity divided by Ah remaining should equal SoC. 400/380.1 = 95.0%.
The batteries can get cool overnight, say 10deg C. But the temperature coefficient is is set to 0.
Peukerts exponent should make the SoC read higher as the current draw when the fridge is running is low compared to the battery capacity.
Any help on this would be very much appreciated.
Thank you.