Extreme Cold Weather Towing - Lithium

[Guest]

I wrote this up on another post for additional info. We recently camped in PA where the nights were 32F for several hours. The lithium battery in the unheated passthrough was at 47F due to residual heat from the furnace set to 70F at night. So inside or passthrough locations on some models will aid in keeping the battery at a reasonable temp. Travel is a different story where a dedicated battery heating pad and a DCDC converter would solve the temp issue under those conditions. Otherwise, I winterized our unit yesterday and pulled the battery to be stored in a semi-heated space in our garage. Ok re-installed it and pulled it again once I realized the tongue jack was inoperative after we arrived at the storage facility. Darn!

https://www.truckcamperadventure.com...ng-system-mod/

Jim

[Country Campers]

Does anyone use a 12 volt Battery heating pad to keep the battery warm?

I am thinking of adding some to my set up as soon as I can find some that will work with what I have.

Brian

[T Alan B]

Please keep me posted. I have one that can connect directly to the battery terminals. It can also be used as a tank warmer. I'm concerned that it may draw too much power while traveling and drain the battery. Any thoughts?

[Mitchell & Kitty]

Excellent thread. I too will be heading south after the New Year and have Lithium. It will take 2 days of driving before we will be out of freezing conditions. My first thought was to just replace the lithium for the trip down with my factory lead acid that I kept. My other thought is to install a 20 watt heating pad to the lithium and insulate it from the cold. I can run the heating pad off of my inverter. The battery is in the bay under the front bedroom. 20 watts shouldn't be too hard on the battery during travel. We would plug in at night to maintain power. Amazon.com : VIVOSUN Durable Waterproof Seedling Heat Mat Warm Hydroponic Heating Pad 10" x 20.75" MET Standard : Patio, Lawn & Garden I'll play with this before heading out to see if it keeps it warm enough. Lead acid will be backup.

[Country Campers]

Excellent thread. I too will be heading south after the New Year and have Lithium. It will take 2 days of driving before we will be out of freezing conditions. My first thought was to just replace the lithium for the trip down with my factory lead acid that I kept. My other thought is to install a 20 watt heating pad to the lithium and insulate it from the cold. I can run the heating pad off of my inverter. The battery is in the bay under the front bedroom. 20 watts shouldn't be too hard on the battery during travel. We would plug in at night to maintain power. Amazon.com : VIVOSUN Durable Waterproof Seedling Heat Mat Warm Hydroponic Heating Pad 10" x 20.75" MET Standard : Patio, Lawn & Garden I'll play with this before heading out to see if it keeps it warm enough. Lead acid will be backup.

They do make 12 v dc heating pads that will not incur the power of 10 rule when using the inverter to power the heating pad.

Brian

[TedS]

Country Campers watts are watts. 120v, 1amp or 12v, 10amps.

[Country Campers]

Country Campers watts are watts. 120v, 1amp or 12v, 10amps.

Yes but I was meaning it takes 10 times the voltage from dc to make the heating pad work, is that not correct, therefore using more battery power than a 12 v dc heating pad.

Brian

[howson]

Yes but I was meaning it takes 10 times the voltage from dc to make the heating pad work, is that not correct, therefore using more battery power than a 12 v dc heating pad.

Brian

As TedS stated, "watts are watts". Whether an appliance is drawing 10 amps of 12vDC (120 watts) or 1 amp of 120vAC (also 120 watts) from an inverter, it's the same amount of power being consumed.

The only difference when using an inverter is that there's some loss due to the inversion happening. How much depends on the quality of the inverter. Some will argue there's also some loss due to the resistance in the wiring due to the high current in a low voltage (DC) circuit (and they are right) but it doesn't change that "watts are watts".

[TedS]

Yes but I was meaning it takes 10 times the voltage from dc to make the heating pad work, is that not correct, therefore using more battery power than a 12 v dc heating pad.

Brian

It take 10 times the current at 1/10 the voltage.

[Mitchell & Kitty]

As TedS stated, "watts are watts". Whether an appliance is drawing 10 amps of 12vDC (120 watts) or 1 amp of 120vAC (also 120 watts) from an inverter, it's the same amount of power being consumed.

The only difference when using an inverter is that there's some loss due to the inversion happening. How much depends on the quality of the inverter. Some will argue there's also some loss due to the resistance in the wiring due to the high current in a low voltage (DC) circuit (and they are right) but it doesn't change that "watts are watts".

True enough... but,,, in my case I already have the 120V heating pad (I brew wine and beer); the inverter plug in is right there; AND I have a 200 AH battery and solar for plenty of power while towing. I can always use a small 500 watt heater at night in the space while plugged in for my travels south until I get far enough to beat the cold.

[Guest]

There is more to protecting the rig than just the battery in sub temps where the plumbing system also needs attention. Buy the way we have several professional taste testers here.

Jim

[TedS]

25 watt brewers pad. 0.2 amps at 120v needs 2 amps from the battery into the inverter. FWIW A 200ah battery could theoretically deliver 2 amps for 100 hours. That should be enough drive time!

[Jlawles2]

Or you could just wire the 2 amp heating pad to the 12V in the pig tail and not worry about the battery draw.

[TedS]

12v won't drive 2 amps through the pad resistance to get 24 to 25 watts of heating. But the 0.02 amps it will drive through the pad will be a smaller draw.

[AlexPeterson]

Regarding a heating pad - the question is how many watts are needed for a given outside temperature. Not easy calculations, with lots of assumptions needed. In the end, it would come down to trying a best guess wattage and waiting around for cold weather...

I'm less worried about the actual time on the road than I am with the storage of the trailer in MN in December prior to leaving for warmer weather. Those heating pads are not known for their high quality, nor do they have overtemperature switches in more than one location. I'm not fond of leaving a heating pad on 24/7 either.

The only way I'd heat a lithium battery is with the built-in systems. YMMV.