Hello. I built an off-grid mobile system with LiFePo batteries, a solar charger, and a generator.
I am using the BMV702 to monitor the battery voltage. This system is sometimes not in use for a long period of time, so I modified it. The BMV702 and BMS were unpowered to save the battery and prevent discharging during this time.
However, after the power cycle, the SOC reading resettled to 100%, which caused the system to behave improperly afterward. Is there any way to get the SOC to keep after the power cycle, similar to the functionality that BMV712 has?
Is a newer firmware version allowing a similar keep-SOC setting as in 712?
The BMV-702 doesn’t retain the SOC value because it lacks non-volatile memory for this specific purpose. When it is powered off, it essentially “forgets” the battery’s previous charge state and resets to 100% on the next power-up. This can cause issues in scenarios like yours, where the system might not be fully charged when it’s powered back on, leading to inaccurate SOC readings.
