Do RV Batteries Freeze in the Winter?

[Big_C]

We purchased four 6volt AGM Lifeline GPL-4CT batteries last fall. For twenty years we have driven down to Mexico for the winter. As Canadians we will have to stay home because of the Canada/US border likely remaining closed for a few more months. We have no idea what to do with our batteries. No one is saying that they won't freeze, they might not or they might not.

Here in our area of B.C. it can get down to -30C/-22F for one - two weeks maximum and some years not so cold. We are forecast to have a colder winter this year. What have any of you done here in Canada or the northern US done with your sealed batteries? Should we take them out or leave them in?

[MEXICOWANDERER]

Chemistry in batteries go near dormant at 0c 32F. Electrolyte eats plates far more slowly. I think BFL13 lives in battery chemistry paradise.

Now imagine this:
Daytime high 115F
Temp at dawn 82F

Hour long commute Air conditioner full blast 5 mph bumper to bumper. Radiator fan on. Battery temp maybe 130F. Cannot touch battery post without screaming.

What is going on inside the battery?

Egads! You don't want to know.

If I could stuff dormant batteries into a chest freezer down here I would. But changing to a tropical blend 1.260 specific gravity is all I can do.

The Lifelines have been dormant since January 16, last. They were stuffed before disconnecting. 14.4 volts @ 60F for 2 days. The standard 31 is 10 years old, the 2-story 31 is 5 years old.

We'll see...

[time2roll]

Self discharge is VERY slow when the battery is super cold.
As long as the battery is fully charged, clean and disconnected you should be fine for 4 to 6 months.

[full_mosey]

There is nothing special about 'RV' batteries with respect to freezing. Assuming you mean lead-acid batteries then, yes, they can freeze.

Flooded will assuredly be damaged by freezing.

AGMs will not be damaged. However, AGMs cannot be charged if frozen and must be brought above freezing to be charged.

I have no idea how to determine if an AGM is, or ever has been, frozen. 🙂

HTH
John

[Sjm9911]

While your board, might be a good time to add a battery disconect switch. Just a thought.

[Tom_M1]

I had a cheap Harbor Freight maintainer fail. It shorted and drained my two Trojan 6 volt batteries which froze and busted. For several years I make sure my batteries are fully charged and then disconnect the negative battery cable. Have had no issues here in Minneapolis where temps quite often will hit -20F or colder.

[mchero]

6+ New Hampshire winters my 93 Pace Arrow Diesel had 4 6 volt Sam's Club batteries.
Late fall I would FULLY CHARGE the HOUSE batteries as well as my two chassis batteries.
Disconnected the negative post on the house batteries and hit the disconnect switch on the chassis batteries.
NEVER froze any batteries.
Never removed any batteries.

For those who suggest pulling the house batteries never mention the chassis batteries on a DP.

DW just told me Justin Trudeau announced the border will STAY CLOSED until the great USA gets the Covid under control.
Looks like that will NEVER happen does it.

[FLY_4_FUN]

Big C wrote:
Specific question to FLY 4 FUN, so you just let the batteries sit in your RV for the winter after charging and disconnecting? FYI ours are AGM, sealed batteries.

I put my twin golf cart batts in my basement for the winter. I do it more out of concern for theft than care of the batteries. If I was in a milder climate and stored at my property I would leave them on and let my solar keep them safely charged.

[MEXICOWANDERER]

A fully charged AGM survives minus one hundred degrees celcius. That's cold enough to affect the tensile strength of many metals. This is why stealth bombers and F22 fighters use (Concorde) batteries. The SR71 cut it's teeth on AGM and to survive ridiculous temperature swings. By the time the aircraft achieved full song the temps on the skin went from -100c to 200c. The batteries compartments of course were heavily insulated. Keep in mind electrolyte density is 1.300

And Mexico is not very fun under cuarentena. The day the musica muerto. Restaurants that feature Covid seating in tourist areas are packed to the gills. Common sense demands a decent sea breeze anywhere there is people. Enclosed areas demanding A/C are not worth the risk, even with less than "normal" amounts of customers. Wandering vendors who either work or starve are an unacceptable risk.

[Big_C]

Many thanks to all for you answers and suggestions. A special thank you to RobWYN who gave me the answer. I found somewhere online that AMG batteries are good in the cold and only start to freeze at -75F or -60C so it looks like we will move the RV from the storage lot, fully charge them here at the house and then disconnect the batteries for the winter.

Not looking forward to our first winter in Canada in over 20 years.

[wa8yxm]

Ok a FULLY CHARGED Lead Acid battery, and this include AGM. Is good down to about -40,, Don't bother asking if that is C or F because -40C = -40F it's the crossover point.

A fully discharged Lead acid battery will freeze at between zero and -1C if I'm not mistaken.

So KEEP Them Full and Keep them happy.

Many if not most modern converters and most Inverter/Chargers have good soild 3-stage or 3-stage plus charger programming.. Some are still single or poor quality 2 stage but even they will keep it in float. .Or slap a battery minder (A big one) on it.. Make sure they are full and keep 'em full and they will not freeze at anything above -40 on either side of the thermometer.

[RobWNY]

Big_C, I have the same four 6V Lifeline batteries wired in series and parallel. I contacted lifeline who said, just make sure they are full charged, disconnect the cables and they will be fine. hey may go from 13.4 to 13.2 over the winter but not to worry about them. I have taken their advice for the past three years. No issue at all. I hope this helps.

[ReneeG]

dougrainer wrote:
Charged batteries will not freeze. Low or dead batteries will freeze. Unless you can gurantee that the batteries will stay fully charged, I would pull them and install a trickle charger if not inside a heated area. Doug

Agree!

Hubby maintains ours religiously throughout the winter AND keeps the FW plugged in. Never have had a problem.

[Sjm9911]

Mine had a hairline crack in it this year after the winter. I assumed it was from the cold. But who knows. It was older so may not have been able to have a full charge. I still keep my batteries on the TT, i do charge them monthly.

[Lynnmor]

TenOC wrote:

Big C wrote:
Sadly we will be parked outside in a storage lot with no source for electricity..

Then store them in a warm place, but not directly on concrete. Why not on concrete, I do not know but have always been told to not store batteries directly on concrete.

If you battery was made more than 75 years ago it might have a hard rubber case, those had a problem with concrete. Otherwise, drop the old wives tale.