Battery Life?

[jojobafanzi]

My 2 AGM batteries were completely flat a few days ago; Also below 20 degrees F that night. No phantom loads. Charged them both all day and let sit overnight. Full charge got to 12.4 volts and dropped below 12 volts by morning. I guess one of the batteries failed and brought the other down with it. Got them from West Marine and installed in January of 2022. They failed 3 years exactly to the day. I'm guessing that is normal life span of this setup? I never flattened my batteries in the 3 years but did abuse them a bit when the generator had some trouble starting a few times. My previous Class B had three AGM's and lasted 13 years. Any thoughts on replacement battery brands? Joe 2016 RT Versatile 170.

[GeorgeRa]

Originally Posted by jojobafanzi

My 2 AGM batteries were completely flat a few days ago; Also below 20 degrees F that night. No phantom loads. Charged them both all day and let sit overnight. Full charge got to 12.4 volts and dropped below 12 volts by morning. I guess one of the batteries failed and brought the other down with it. Got them from West Marine and installed in January of 2022. They failed 3 years exactly to the day. I'm guessing that is normal life span of this setup? I never flattened my batteries in the 3 years but did abuse them a bit when the generator had some trouble starting a few times. My previous Class B had three AGM's and lasted 13 years. Any thoughts on replacement battery brands? Joe 2016 RT Versatile 170.

I am on the second set of 2 x 115AH 12V Fullriver batteries set. The first one lasted 11 years, it was still OK but had reduced capacity so I precautionarily replaced it. https://fullriverbattery.com/batteries/part-dc115-12/

[booster]

Assuming they were a good battery brand that is know to have decent life, 3 years would be on the low end of what we normally hear. It does happen, though, depending on the use patterns, discharge depths, and quality of the recharging process. And of course how many days a year they are used. Most normal OEM setups and discharges to 20% or lower regularly would probably be in the 3-5 year life average. Lower discharges and better equipment can go longer, like George's or ours that I changed out at 8 years but they still tested at nearly new capacity, so they would have lasted quite a bit longer.