Batteries Damaged? Or can they recover?

[Bailey'sMom]

Hi All

So last summer I had an issue with my fridge staying cold on propane. (I don't have electric where I camp) My last 2 week trip of the season, I brought a portable refrigerator/cooler that can run on 12V.

I have solar so was hoping to be able to keep batteries charged up sufficiently to be able to use this mini fridge.

Well, we didn't have a lot of sun, and my batteries got scary low. I stopped using it and switched to a plain ice chest. When I got home, I recharged my batteries.

Then a couple weeks later, I took my camper to the dealer for a bunch of things including checking out the fridge and why it had the propane problem. They claimed it was that I ran the fan too much and something with the vent. I doubt that was the issue, but I won't know til I use it again. I plan to test it later this week. ANYWAY.....

When I went to pick it up from the dealer, I saw the batteries were down to 11.6 or maybe it was even a bit lower. I could not believe it!! I asked if they had the camper plugged in at all. They said no, not really. I was surprised that solar didn't keep the batteries charged. Then I found out it was inside most of the time so no sun.

So.... long story ... but my question becomes this:

I have camper stored in my garage thru the winter while plugged into a Battery Tender (as recommended by Bill). When I took it out Sunday and set it up, it appears that the batteries are fully charged and doing fine.

Will the batteries actually recover from being so terribly low? This is kind of what the battery tender is supposed to do. Just wondering if you think they really will recover from being that low, or if I will need to plan to replace the batteries soon.

Thanks for reading thru the entire story, and for your words of wisdom..

[rickst29]

But the only way to know for sure is to install a 'coulomb counter' meter, charge them up, and then run them down into a substantial load (such as the fridge). A coulomb counter will tell you the actual Amp-Hours which the batter pair was able to deliver.

I have found this one to be reliable, although it does add another phantom load right at the batteries: https://www.amazon.com/AiLi-Battery-.../dp/B07FGFFHC6

[Bailey'sMom]

Originally Posted by rickst29

But the only way to know for sure is to install a 'coulomb counter' meter, charge them up, and then run them down into a substantial load (such as the fridge). A coulomb counter will tell you the actual Amp-Hours which the batter pair was able to deliver.

I have found this one to be reliable, although it does add another phantom load right at the batteries: https://www.amazon.com/AiLi-Battery-.../dp/B07FGFFHC6

Thanks Rick

I sure hope they are recovered. I will probably hold off on purchasing that, and just see how my real world experience goes this trip. And hopefully I have plenty of sun this summer.

[Larryjb]

What voltage you you have once fully charged, and drawing a light load (such as running interior lights)? This might give an indication of the overall health of the battery.