Tuesday, September 27, 2022


Be kind to your RV batteries this winter

By Chris Dougherty
I have helped out a number of folks who had destroyed their RVs batteries. What happened? In each case, they discharged during storage, froze and cracked apart.

Most RVs have parasitic drains in their electrical systems. These drains come from various electrical components, like carbon monoxide and propane detectors, car stereos, circuit boards, LED lights, relays, and so on.

Some drains will remain on even if an RV equipped with an OEM battery switch is turned off, to maintain memory in the stereo, and to keep CO and LP detectors operating.

Where this can become an even bigger problem is in freezing weather. Lead Acid batteries will freeze if they lose their charge, which can result in their splitting apart. In any case, when they freeze, they are damaged beyond repair.

If you store your RV with the batteries in it, you should make sure that you have the batteries charging. This can be accomplished using shore power, or a solar charging system. The solar charging system should have a high enough charging rate to overcome the parasitic drains on the system.

Regular battery maintenance should continue, including keeping the batteries clean and filled with distilled water.

If, however, you don’t intend to use your unit for a season, it may be better to remove the batteries from the unit, and store them in a climate controlled area on a shelf up off the floor.

Photo by Steven Weppler on Flickr

Chris Dougherty is an RV Certified Technician. He wrote this while serving as the technical editor of RVtravel.com, a position he hold today with Motorhome and Trailer Life magazines.


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Bob Robinson
2 years ago

Proper storage temp for batteries in full charge State is 50 degrees or less and with the new modern plastic battery cases storing on wood or other is really not necessary. I suggest a quality Battery Tender rated for DEEP CYCLE should be 1500 ma/1.75 amp but only 1000 mah/1amp for starting batteries (engine type). All batteries should be fully charged before connecting any maintainer device as they are not engineered to charge batteries but maintain charge. Storing in heated area is your enemy as discharge occurs more rapidly. A fully charged battery will not freeze until -72 degrees but will form ice crystals so always check the cell first and make sure liquid is at proper level. A dead battery is more dangerous than a full charged battery So always disconnect NEGATIVE FIRST. I have 37 years in the battery business. Hope this helps those who are not battery experts.

Steve Winterowd
2 years ago

You mention that solar needs to have a high enough charging rate, but you don’t say what that rate is- not necessarily helpful.

2 years ago

First thing I have done when I installed the battery was to install a master kill switch. I turn the RV off every time it’s parked and through winter and I’m going into winter 5 with the same battery. This spring we will see what time does to it.

2 years ago
Reply to  Joe

It would live longer if you plugged it into a good ctek tender or similar when you’re not using it. If it’s parked outside a solar trickle charger would help too.

chris p hemstead
2 years ago

Why off the floor?

Mike Sokol(@mike)
2 years ago

That used to be true with Edison batteries 100 years ago, which had a steel case and glass cells. If you put them on the floor the rust would warp the fittings around the glass cells, causing them to rupture. Later batteries (perhaps through the 1950’s), used a rubber and tar case which could absorb moisture from the concrete. But modern batteries have a case that’s impermeable to any sort of moisture, so they should be safe to set on the floor. Just don’t set anything on top of them that could short out the terminals as that would be very bad.

chris p hemstead
2 years ago
Reply to  Mike Sokol

Exactly.. that’s why I was asking why he said it.

2 years ago

Hi, Is there a way to disconnect the stereo, and the CO and LP detectors from operating? Also, I am a single senior. I would like to take the battery out and put it in the house, but it’s very heavy. Do you have any suggestions for doing this?

2 years ago
Reply to  Arlene

They make a battery carry handle that greatly assists in moving batteries. Also, depending on finances, you could replace your battery with one of the new lithium LiFePo4. They are less than half the weight of flooded lead acid (FLA) and last more than twice as long (only discharge FLA batteries to 50% max and down to 80-90% max with lithiums).

2 years ago
Reply to  Arlene

Grandchildren, young people at church.

Bob Weinfurt
2 years ago
Reply to  Arlene

Its more practical just to leave the batteries in it. Actually, the battery won’t degrade as fast being stored in a cooler environment. Removing the negative terminal will prevent any draw from it. (If you have two batteries, do the same to both) Invest in a one amp trickle charger and once a month hook it to the battery overnight. Repeat on every battery in your coach.

Brad Teubner
2 years ago

Self discharge doubles every 10C. Best storage is fully charged and as cold as possible.

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