Well it happened! Drug the old girl out of the shop for a ride, wife and I put on our gear and I pushed the button and click click .......... 2 year old (almost to the day) AGM battery dead. Put a meter on it and had 3 volts. Jumped it with my truck and it fired right up and it read 13.4 volts. Shut it off and had 12.6 hit the button and boom 3 volts. My question is is this common with AGM batteries?
I love AGM batteries but seems like they act just like a Lithium battery when they get old, they just die a quick death, at least that's been my experience, I make sure I have the correct tender on when it's been setup for a while :nix:
Yes, that is how it happens sometimes. It seems to me that once they drop below 12 volts, they just don't recover as well, and once that low, they lose the rest of the voltage very quickly and will not hold a charge after that.
A battery tender is your friend.
An AGM battery (actually any battery) needs to be maintained on a "Float charger" anytime it is stored.
A Battery Tender used to be the only one that did this well but many chargers now have this feature.
I have 2 of them now and don't even use my big old chargers any more.
An AGM battery is the best choice for your HD, they take the vibration better and don't vomit acid and will last 4+ years.
This battery almost always had a tender on it. Was a little dissapointed with the the life of it but was surprized at the suddeness of death.
The AGM in my FLH has usually been on a tender. It's pushing 5 years now so I figure it's days are numbered.
Best I get is about 4 yrs with tender of course on HD batteries.