Battery charging question

I know it's going to be a few more months before I even consider bringing my boat out of storage, but I was wondering about charging my cranking battery. This is the first time I've been in a location where my boat was stored over the winter months. It's stored in the boat with the cables removed.
I've been told to bring the battery inside and trickle charge it in the basement (in a tray of some type to prevent leakage) over several days before the season starts. Someone else told me that I could leave it in the boat with the cables disconnected and trickle charge it for just 12 hours prior to using it the first time. I'm just not sure which is the best method (although I have the feeling the boat location is the safest) so I thought I'd get some opinions from you guys. Any help would be greatly appreciated.

A fully charged battery is not bothered by the cold. In fact cold temperatures reduce the natural self discharging that takes place when a battery sits idle.
If it's easier to leave it in the boat then by all means do so but I would give it a couple of trickle charges over the course of the winter just to be safe.

I store the boat in the garage, I leave the cranking and two trolling in the boat but I will charge all every two months until Spring.

I agree with leaving it in the boat. I have done that with my boats and bikes for years. Make sure it's charged before putting it away and it should start without trickle charging in the spring. I have know 2 people to lose batteries to trickle charging not sure why, possibly over charging? Crappy trickle charger? If you have problems in the spring The battery has more then likely run its life and you don't want to have to depend on it on the water. When in doubt a quick load test will confirm if it's good or bad.

Tom

After thought. Keep the battery top clean to prevent a current draw and if you don't have one invest in a cheap volt meter and check the volts over the winter. As said before a good battery will hold its charge

Tom

You bring up a good point about crappy trickle chargers. The cheap transformer type that plug into the wall outlet is one. They are the constant voltage type, and when a battery is fully topped up the charging voltage will creep up to about 15.5 volts. This creates a lot of off gassing, and with the newer style batteries that have very little electrolyte (eg. sealed lead acid, AGM) these batteries could be ruined by that type of charger.

Thanks Buddy great explanation. Also to note undercharging. I purchased my current boat 5 seasons ago and it was my first boat to have a deep cell for the trolling motor. I was charging it with a cheap trickle charger and found the battery was dying fast on the water. i wasn't checking the voltage after charging but it was an automatic on/off charger that was left on for weeks and o figures it was good. With out testing the battery I bought another and found the same issue after a few weeks. It turned out the charger wasn't fully charging and by only half charging it didn't kill the first battery but it took half a season of charging and draining and recharging to bring it back to almost what a new battery would be expected to perform at. Glad I didn't throw it out before figuring it out now have 2 for longer days on the water

To

I trickle charge my cranking and trolling motor batteries every month, I use a battery tender I bought from CT, I store my batteries in the basement sitting on a piece of Styrofoam, I'm assuming this is an ok method but not 100 % sure.

Thanks for the info guys. With my boat shrink-wrapped, the batteries are in there for a couple more months. I'll get them out at least a couple of weeks prior to when I may use the boat for the first time and work on the charger. Hopefully they'll be ok. I'll remember this next fall to take them out and put them in the basement before shrink-wrapping.

With todays battery technology, just charge them up, leave them in and forget about it. Disconnecting the cables or turning the battery switch off is a must incase your boat has a parasitic draw.

storing in basement is same way I do it, take out of boat make sure batteries are topped up with distilled water charge up and check every month with trickle charge store in cool place. i've seen batteries freeze in the boat if it should fall below 12 volts and the water freezing can cause damage to plates
"A 100 percent fully charged battery will not freeze until approximately minus 76 degrees Fahrenheit. A fully discharged battery can freeze at or around 32 degrees," The difference between a fully charged and discharged 12-volt battery is not that big.When I'm talking about a fully discharged battery, I'm not talking about zero volts. A fully discharged battery is just below 12 volts. There's only about eight-tenths of a volt difference between a fully charged battery and a discharged battery,

Salmonslayer is correct about discharged and partially discharged batteries freezing. Not only can it damage the plates but it can break the case. In the spring you'll have a bilge full of battery acid.

If they're not fully charged, I'd be calling my shrink wrap guy and getting a price on getting a door added. My shrink guy charged me 80 bux for a nice zipper door and I save it in the spring and he sticks it on each year.