Due to a freak storm this week, we had to rely on our generator for several days. We have a Scorpion YTX14 AGM battery in it that is six years old. It started the gen several times during refueling/oil checks and then, poof, complete failure and it's only measuring 0.41 vdc. I'm thinking the vibration maybe broke a plate? Luckily, the replacement is only around $60 so the replacement won't be too awful. I don't think six years life is too bad....was expecting more but I also don't think this battery really owes me anything.