I bought a new battery 4 years ago when my '03 Oddy battery failed to hold a charge. Before replacing the battery, I discovered the positive terminal was slightly loose, so it turned out that the previous battery was fine! The new battery couldn't be returned so I kept it in the garage for the eventual day...

Well, that day has come. Is there any reason I shouldn't get good service from an unused 4-year-old battery?

I'm sure it needs charging. I have an old but trusty Sears charger, but it's been so long since I've used it, I can't recall the protocol and I've lost the instructions. It has three settings: 2-amp (trickle), 10-amp (normal) and 50-amp (start). Seems like it said to charge the battery until the meter reads 50% of the selected charge rate... So at the 10-amp charge rate, a meter reading of 5 amps would indicate a full charge. Can someone confirm this is correct?

BTW, the OEM battery (circa 2003) and the current battery each lasted 8 years, although that's probably because I rarely drive this vehicle. It only has 55k miles!

 

What is the state of charge on the battery and how was it stored? Lead acid batteries will discharge slowly over time and if they discharge too far they become susceptible to freezing. If that happens consider it dead. If you're certain its not ever frozen you might be able to bring it back.

 

After 4 years, I didn't bother checking the voltage before hooking it up to the charger. The battery has been stored in my garage. In my climate, there's no way the temperature ever came close to freezing. I charged it for a couple of hours last night. I'll give it a few more hours today but I'll keep an eye on the charging meter. As I said, I think it's supposed to charge until the meter reads 50% of the charging amps.

 

A lead acid battery that sits unused will sulfate(google it) making it fairly useless.

There are battery chargers that claim to be able to reverse this process,but Ive never bothered trying.

Save your self a potential headache and just buy a new battery,