Battery Charger

[Zeus1972]

Since we purchased the camper nearly 4 months ago or so and at that time found out that the battery was original (2007 model year camper) we purchased a new battery but now that we are closing it up for the winter we pulled the battery off. What does anyone recommend for a battery charger to maintain the battery for the winter?

[NMWildcat]

If it was me, I would leave the battery in the RV. I would ensure it was 100% charged using the RV converter and then employ a battery cutoff that cuts off ALL power demand (or take one of the leads off the battery itself). It will then be good for several months. If you liked, you could always turn the battery back on every few months and top off the battery with the converter if you have access to shore power.
Otherwise, any modern battery charger will do when the battery is out of the RV. Some folks charge the battery every 6 weeks or so, some employ a full time trickle charger. You can spend as much or as little as you like on a charger/tender.

[5picker]

Yep... a fully charged and then properly disconnected battery will NOT freeze unless it gets somewhere south of -70º and will only loose about 40% of its charge in 4-5 months.

Charge it up and leave it right where it is.

[Chuck_S]

There have gotta be several threads running asking the same question. Answer is the same for all: fully charge, disconnect completely, leave on trailer. Details in the other running threads.

-- Chuck

[NMWildcat]

Originally Posted by Chuck_S

There have gotta be several threads running asking the same question. Answer is the same for all: fully charge, disconnect completely, leave on trailer. Details in the other running threads.

-- Chuck

Good luck in your quest to relieve duplication! I believe most of the thread subjects and replies in any forum are duplicated many times

[TitanMike]

Originally Posted by 5picker

Yep... a fully charged and then properly disconnected battery will NOT freeze unless it gets somewhere south of -70º and will only loose about 40% of its charge in 4-5 months.

Charge it up and leave it right where it is.

I kind of went a different route which I highly recommend if there is 120 Vac available.

All that's been mentioned does "freeze proof" a lead acid battery but it doesn't halt sulfation. If a battery is discharged ANY amount (and all lead acid batteries self discharge) lead sulfate is formed. That's just how lead acid batteries work. The longer the sulfate remains the harder it is to convert it back to lead and the sulfuric acid/water electolyte.

Yes, the battery may only have lost 40% of it's charge (some more, some less) but fact is that not all of the sulfate will be removed as it may have sat there for 6 months.

To prevent this I preferred (past tense as I now have Lithiums) to use the converter to maintain the batteries. If not the converter than at least a battery maintainer sized to the size of the battery bank. Large enough to replace all that is lost by self discharge. Average self discharge can be ~5% per month at average temps. More when hot, less when cold but never none. If you want maximum life, and full capacity, you can't really let a lead acid battery sit in any partially charged state.

I suspect that those who are getting the long life out of their lead acid batteries are maintaining them at full charge at all possible times and just checking water regularly.