Off-Season Battery Tender/Charger for Starting Battery

I keep my boat in secured storage about two hours away from my house. I don’t get up there at all, really, in the off-season. I do have an on-board charger but am hesitant to leave it plugged in for 5 months with no one around. I went up to get the boat yesterday and discovered the brand new (last year) starting battery is toast. Brought it into Batteries Plus where I got it and confirmed it (they honored the warranty and exchanged it for free). From now on, I am going to bring the battery home during the off-season and leave it in the basement. What chargers/maintainers have you found work well for you? It’s a dual-purpose Group 27 Duracell AGM.

I have 3 different maintainers. a battery minder brand and a diehard brand and a cheap northern tool model and they all work good. I don’t think there is much of a difference between most of them

Minn kota 3 bank has kept mine going over 10 year. Always plugged in, only turns on when needed. Even though it’s self protected. I run a surge protector since it’s in a rented spot. For extra level of protection.

Any of the name brand chargers are fine. I would not over think this.

Noco.

I leave mine plugged in all winter to Noco onboard charger and loose batteries plugged into other Nocos whenever they aren’t being used.

I was in this exact same situation this spring. I had 1 year old Interstate lead-acid starting battery that went down to true zero charge over the winter and it was a bugger to nurse back to life. Chargers were not recognizing it. I had to use a “dumb” charger to pump some voltage into it, did a Noco repair cycle, top off the water, then discharged it some, and trickle charged it with the $30 Noco 1A. It seems happy now.

Next year they’re coming inside.

I pull mine when I store it and leave them in the garage not heated, off the concrete. I put mine on 2x4s and move a tender around once in a while to keep them charged.

I leave it plugged into on board charger all winter. No issues.

John Rasmussen wrote:

I pull mine when I store it and leave them in the garage not heated, off the concrete. I put mine on 2x4s and move a tender around once in a while to keep them charged.

Thanks everybody. This is was I plan to do moving forward. Which NOCO charger have you guys had luck with? Specifically for deep cycle batteries?

John Rasmussen wrote:

I pull mine when I store it and leave them in the garage not heated, off the concrete. I put mine on 2x4s and move a tender around once in a while to keep them charged.

This is exactly what I do with my trolling motor batteries. I have gone back and forth pulling the starter battery. The marina I store my boat at charges like a $30 in the spring if you don’t have a battery in there….

tmyboy2001 wrote:

Which NOCO charger have you guys had luck with?

I don’t think you can go wrong. Kind of depends what you want it to do.

If you just need a single, trickle charger, a Genius 1 or 2 should do nicely.

NOCO Genius

The only thing I would do differently is not store them in the basement as you said in the 1st post but store them in the garage like John said. As long as the battery is close to fully charged it will not freeze until -75degrees and it will discharge much slower at cold temps than warmer temps.
I worked with a retired electrician at a big box store. He firmly believed that anyone the stored a lead acid battery in their basement was a prime candidate for a Darwin Award.
He showed me 2 articles about house fires started by the hydrogen gas given off by a battery that was being charged being ignited by the furnace or water heater. He had another article about an aluminum pan falling off a shelf onto a battery and the resulting short caused a fire.

I don’t see any problem storing your batteries in the basement as long as it is not in your utility room or in a room where there is a flame source. I just leave my on-board charger hooked up all winter long. I don’t see any difference in that over a battery tender. I pull the batteries if I am not storing it in a heated area.