LiFEPO4 and cold weather

[Rocketsled]

I'm looking at the cold weather heated battery options and they're double the alternative.

I then see those tank heater rubber pads...and they have a thermostat that protects water from freezing (nearly identical use case, on at 45F off at 67F), and they run off 12v.

So how bad an idea is it to insulate the batteries and wrap them in a tank heater? Our trailer is a 3 season unit, I can't fathom actually boondocking in temps where it'd be a factor, and those tank heaters are really inexpensive.

(e.g. I'm not going to be charging them when it's that cold, but I can warm them up if I need to...)

[notanlines]

A charged battery will not freeze (at North American temps). I’m not sure what advantage you’ll gain.

[Rocketsled]

The ability to charge them in colder temps...but I'm figuring they'd go 3 days without us rationing, so it'd be pretty easy to wait til the sun puts a little heat on the battery box to get them above freezing.

Mostly I'm afraid of something stupid...The trailer's at home, on the street, hooked to shore power, and the charger decides to add power to them (maybe they're down a little from when they were used last.) Low temp protection is the only major feature I see between a $400 battery and a $1000 one.

We used the trailer over Xmas one year where temps were in the 20's...based on the volume of Propane we went through, it's not a good deep winter trailer.

[Zoopster]

If you purchased the cold weather option for the lifepo4 batteries you won’t have a problem. They are “smart” or “stupid” sometimes and will keep battery warm automatically if cold so they can charge properly. Li batteries don’t like cold.

[Zoopster]

Actually the cold weather option on the lifepo4 Blue batteries is only $100 more

[Rocketsled]

$965 vs $400 for Ampere Time…times two.

(I’m assuming you’re referring to these? https://www.lifebluebattery.com/rv-b...m-battery.html )

[Zoopster]

You are correct sir

[Javi]

Please remember that both the upper and lower limits for charging are not the outside or ambient air temperature it is the temp inside the actual battery.

If your batteries are equipped with BMS to shut off charging at 24-32 degrees it is unlikely that you will ever actually see it stop charging unless your batteries are outside and the temp has been below freezing for several hours..

I regularly camp during the winter and I didn't buy nor was it recommended by Battle Born that I buy the heated batteries for my trailer. I keep them in the un-heated front compartment.

[Rocketsled]

This is very helpful! I'm planning on having them in a metal box on the tongue of the trailer...I don't want to chop up the existing wiring (like mounting them inside) as I will return the trailer to stock when we upgrade in a few years.

[Stircrazy]

Originally Posted by Rocketsled

This is very helpful! I'm planning on having them in a metal box on the tongue of the trailer...I don't want to chop up the existing wiring (like mounting them inside) as I will return the trailer to stock when we upgrade in a few years.

the other thing is like you were originaly planning is to make the mettal box two inches bigger all the way aroeund, line it with two inches of foam and put a little 12V silicone heating pad in there that has a temprature controled on/off switch and a total disconect. here is a set up for about 30 bucks CDN so 1.99US simple cheep insurance just incase you came when its cold. even if you don't use it 99% of the time, being in a thin exposed metal box there is a chance the batteries could cool off enough when usage is low.

https://www.amazon.ca/Waterproof-Sil...dp/B010B2A3KI#

https://www.amazon.ca/dp/B078S2J7CY/...xpY2s9dHJ1ZQ==