I have a pair of 165AH AGM batteries (Victron BA412151080), wired in parallel for a total of 330AH at 12v.
Recently the state of charge was showing 57% remaining, despite 209Ah consumed - i.e. it was showing that only 43% had been consumed, when in fact 63% had been used.
How can this be, please? Do I have a faulty SmartShunt?
A couple of days later, and without charging the battery, the SmartShunt started showing 100%. This was without intervention from myself and despite the fact that the battery was even further discharged - you can see this from the voltage level, which I did not notice at the time.
I now realise that I allowed the voltage to get low enough that the batteries may have been damage, which is extremely annoying considering I was relying on the SmartShunt to monitor them. I never allowed them this low when I was using my boat's simple voltmeter!
Have I done something wrong please, or is this a common fault of SmartShunts?