5 y/o AGM batteries
I have a simple setup of 2x 12V AGM [email protected] batteries in parallel for emergency power. I have only discharged them 2 to 3 times in 5 years (lowest drain was 12.2V). They sit always fully charge at 13V, I recently tried to use them for a power outage and they went from 13V to 12.4V in 20 minutes just running a radio and a few light bulbs 100watts.
By not using them and keeping them always charged on float kill them? How can I prevent this from happening when I buy my next set? These were $179 a piece, costly mistake.