100W solar panel with Victron Shunt

[creativepart]

Raj, buying a cheap LFP battery without low temp charging cutoff will be a big mistake.

While you can take power from those batteries in the cold, any charging below mid-30’s can ruin the battery permanently. In short a bad choice for use on the A-Frame of a travel trailer exposed to cold temps.

[Marine359]

Cheap Insurance: put a thermostatically controlled tank heating mat on the battery with a switch. When not using the rv, switch it off. When using the battery in ambients approaching freezing, switch it on. It will heat thermostatically at 40F, and stay on as long as ambient is 40F or lower. $37. Mine worked great.

Bob is correct. Low temperature protection means the BMS shuts down battery output at spec temperature, which is usually 20F or below. It’s not the same as low temp charging protection. Only high quality batteries have this feature where the BMS will not allow the battery to accept any charging below 32F.

It’s helpful to have an IR pistol thermometer when it gets cold.

Lived in California for over 30 years. Freezing temperature are a threat 10 months a year in the Sierras, and wintertime in desert areas. We had a MH back then and experienced unexpected freezing temperatures when camping in shoulder season.

[raj]

Looking at the manual which came with the battery, it says:
The BMS will not allow a charging current under 32°F (0°C) but will continue to discharge down to -4°F (-20°C)

[Marine359]

Looks like you’re good to go Raj.
My battery has low charging protection, but I still installed a heating mat. All it takes is to get trapped one time in a place where you can’t charge your battery.

[BobC]

Originally Posted by raj

Looking at the manual which came with the battery, it says:
The BMS will not allow a charging current under 32°F (0°C) but will continue to discharge down to -4°F (-20°C)

Great! Too bad they didn't get their info straight on Amazon and their website. I'd still take Marine359's heating advice. In some of Will Prowse's teardowns, some batteries that technically have low temperature charging protection have temperature sensors that aren't correctly installed or otherwise don't function properly.

[Marine359]

Back up plan if you don’t get heating mat: carry a small ceramic heater and a 12v usb fan. If battery shuts down, start generator, plug in ceramic heater, and use fan to blow warm air onto the battery. That’s how we rescued ourselves before we got a mat.

[raj]

As a followup:
I'm back from my first trip with this setup. I found that we really don't tend to use much electricity. Most days, the batteries (I have 2) were around 85% or higher in the morning and usually they charged back to 100% before 10am! Thus, it looks as if our power issues are taken care of. Since we seem to have such more "extra" power, I purchased a small inverter (300W) which is sufficient to charge laptops as well. In short, I like it and I think it will work out well!