Is a battery that tests good but has a low max voltage still useable, or is it time to replace?
This car is mostly used in winter, so other times I use a battery maintainer once per week. If I disconnect the battery, charge it, wait 12 hours, and check the voltage, it is 12.45V on my Fluke meter, T = 76F.
So I brought the battery to AutoZone, and their battery tester showed the battery was Good, but needed a charge. I had AutoZone charge the battery, and the voltage results were the same 12 hours later.
It’s a maintenance free battery, so there are no ports to access the cells.
Good, Needs Charge
State of Charge (Soc): 65%
Cranking Health: PASS
Reserve Capacity : OK