Cold Climates and FLAs

[123easy]

Hello;
I have a question regarding FLA battery life in cold climates. I understand batteries can last much longer in the cold. Since the batteries capacity goes down in the cold and battery life is a function of depth of discharge is this a double edged sword? If capacity is halfed from cold is a 10% depth of discharge when at normal temperature now 20% or is it the same amount of sulfation regardless?
Thank You

[SunEagle]

I would say the battery manufacturer should be able to provide discharge % rate information based on ambient temperature. Along with that data they should also provide cycle rates based on % discharge

[Mike90250]

the link here

http://support.rollsbattery.com/support/solutions/articles/5860-temperature-vs-capacity-flooded-lead-acid-batteries

covers the loss of capacity when cold. This would be pretty much the same for AGM or flooded batteries
FLA capacity cold battery.jpg

[123easy]

Thank you for the replies. It would seem that cold could only effect battery life adversely. Less capacity equals deeper discharge. Yet there are repeated references to much longer battery life in cold climates??? Is this only for stored with float charge batteries?

"And we had folks in Canada that could get 12+ years from their battery banks that cold soak unused in winter (stored fully charged, perhaps with a small "floating solar array") where we would expect 5-7 year life in the lower 48 states."

[chrisski]

This is a guess of why batteries last longer based off what I’ve seen with other chemical reactions.

I think batteries in the cold “last longer” because thE output less volts. My understanding is the cold slows down the chemical reaction.

If you have a load that will run on whatever the battery puts out, it’ll last longer. An old fashioned light bulb will do this, but it won’t glow as bright during that time. A lot of loads will draw a constant watt so you’ll get more amps to make up for the less volts, so there will not be as much of a difference there.

I am unwilling to use my $250 battery to test this, but I’ve seen this in other-than-battery chemical reactions, mainly glow sticks. Put them in the freezer to last longer, but the glow dims to next to nothing while they’re cold. Take them out, they warm up and glow brighter and die quicker. I’ve extended the life of a 2 hour glow stick to 24 hours doing this, but while in the freezer put out almost no light.