Has anyone experienced big-name LiFePO4 batteries rapidly loosing their ability to hold power after just two years of easy use? I have, in my class C RV, a bank of three 100 ah batteries with 400 W solar, 40 amp controller and 2kW inverter which was used only a few times. The RV was mostly stored, 50% discharged, for 2020. Most usage ran between 50-80% SOC with occasional full charges and one discharge to 10% SOC when we were stuck in southern TX during the deep freeze and power outage. Up until a week ago I saw no sigh of battery degradation. Using the inverter on a fully charged battery bank to cook on a 1500 W convection plate, in a matter of minutes I received "low voltage" warnings. Now, my 7 amp draw refrigerator takes the bank down to low voltage warnings (12.5 volts) in less than 1/2 hour.
The start of this tour began in mid June. A few weeks into it, I did notice that the battery voltage was slightly lower than it should have been for the stated SOC (ah drawdown) from the Victron BMV-712 battery monitor. Other than that, everything seemed normal until there was a larger discrepancy noticed a week or so later. The solar was mostly keeping the battery bank up to near full.
The start of this tour began in mid June. A few weeks into it, I did notice that the battery voltage was slightly lower than it should have been for the stated SOC (ah drawdown) from the Victron BMV-712 battery monitor. Other than that, everything seemed normal until there was a larger discrepancy noticed a week or so later. The solar was mostly keeping the battery bank up to near full.