Battery voltage for winter

Liberty44140

my boat was hauled Monday and they left the blower on so when I checked it this afternoon the house batteries were dead, no power at all. Engine starters were fine. I charged them on the house charger and got them to almost 12.2v on the digital meter before I had to leave. I don’t plan to return until early feb, disconnected the black sides. These are grp 31 marine deep cycle, one has 3 seasons on it and one has 1 season on it. Should they be ok to rest for winter at about 12.2? I could go back in a few weeks and bring them home but it’s an hour away so I’m hoping to not have to make the trip. 

Handymans342

They should be fine but I would not use the boat charger to bring up the batteries in the spring. 

Liberty44140

Thanks, use a trickle or a larger charger?

Handymans342

Larger unless they are in your garage and full volts then trickle.

Dream_Inn

I'm not sure I agree.  I wouldn't leave my battery at less than 50% charged for that duration. 

Here's a bit more info on batteries to help you decide:

https://deepcyclebatterystore.com/how-to-maintain-batteries/

Liberty44140

Thanks for the info. I’m kicking myself for not just bringing them home, didn’t have much time. One is still under 24 month warranty so it would be covered but now I’m thinking that sometime in the next 3 weeks I’ll just get out there and bring them home. I’m assuming a few weeks at about 50% can’t hurt much? 

Dream_Inn

A few weeks should be fine.  I just wouldn't leave it that way all winter.  Even leaving in the boat is fine, but you want them stored fully charged.  Only thing that you have me curious on, are they tied together?  I ask because you state one is 3 years old, other is a year old.  I'm sure you know that they should be the same age (& same battery) if tied together.

Liberty44140

Thanks, I am going to get there and bring them home. They are tied together. I am aware (thanks to this glorious site) that you should not tie a good and bad or new and old battery together, but I did not think that two batteries that are two seasons apart would be bad. One was bought April 2016 and the other April 2018. I think I may just get them to Autozone soon and see how they test out. Thanks!