Batteries

[Toads]

I have 3 exide 31 series batteries I purchased a couple years ago. I think 2 of them has been sitting dead for about a month or so. I always plug charger up every weekend but I noticed after a couple fishing trips that the trolling motor doesn’t even last a couple hours. I found there was a little corrosion on the terminal so I assume it hasn’t been charging at all. The charger would light up green as to show a full charge. I cleaned up the connections... So are these batteries no good after sitting for a month dead or will they come back to life? How could I test them at home?

[CatFan]

Just measure the voltage on the battery.

[ifishinxs]

Yeap, check with a volt meter.

[Toads]

The 3 batteries have only been off charger for only 1-1 1/2 hours. They read 13.21, 13.24, & 13.28. Would this be a accurate reading or should I allow them to rest longer?

[Rip Bass]

They need to sit for about 24 hrs for an accurate reading. Full charge should be 12.65 v or a bit more. But even if they show a full charge it could be a surface charge and not last long. After they sit,run the troller for 30-60 seconds and check them again. If they show a drop,they are bad.

[Toads]

I also inspected the levels inside the battery...on 2 batteries the cells were exposed. I added distilled water and one of them took about 3/4 gallon. That seems like a lot to me but I’m not a battery guy. Would these still have any life left or are they toast?

[hekistner]

I also inspected the levels inside the battery...on 2 batteries the cells were exposed. I added distilled water and one of them took about 3/4 gallon. That seems like a lot to me but I’m not a battery guy. Would these still have any life left or are they toast?

With using that much water I'd say it is toast, time to do a load test and I'll bet they don't hold up during the test voltage drops below 11 VDC as the load is applied. A good battery should hold above 11 VDC for a count of 10 otherwise it's bad.