LiFePO4 with cold temperature protection (lithium)

[MarCorpsMustang]

Originally Posted by markopolo

Battle Born
https://battlebornbatteries.com/
No internal heater, instead it relies on a low temperature charging disconnect at <25F, low temperature charging resumption 32F. Balancing is triggered at 14V.

Thus the reason I have four BattleBorn batteries.

[Winston]

We were stumbling about the Internet in pursuit of certain 'lithium' issues/options when we happened-across SolarPanelTalk - - another forum rich with lithium knowledge and opinions. And these people possibly have more history/experience than we RV'ers do - - we found many reports of systems in-service for more than 5 years. They call themselves "Fractional C" users, a term we only partially understand, but a term we've heard applied to RV'ers. In short, if one is patient enough to cull through some lengthy threads, there are a lot of nuggets to be found.

Here's one: "Simplified lifepo3 charging and care" dating from August of 2014, but still active: https://www.solarpaneltalk.com/forum...and-care/page2

And while searching for sources of lithium batteries (in particular, our namesake, Winston), we discovered: "Winston LPF life?? Real world usage": https://www.solarpaneltalk.com/forum...al-world-usage

We suspect there's lots more good reading here - - just haven't had the time.

[nebulight]

Fractional C refers to the amount they charge or discharge. A "C" is a unit of measurement for how much you are charging or discharging from the battery. So if you have a 100amp hour battery and you are discharging 100 amps, then you are discharging at 1C. If you are discharging at 50 amps, then it's .5C.

Most RV users are fractional C users since most of the time, it's usually small DC loads and solar charging. On a B van you probably can't fit more than 600W of solar so at most you'd be charging at 40 amps. If you have a 400ah bank and charging at 40amps then you are charging at .1C. Most users and most battery types other than lithium don't really allow for over 1C charging or discharging. Lithium with it's very low internal resistance can have max charge or discharge rates approaching 3C. However with drop in replacements with mosfet based BMS units, there is no way you'd be able to do that. DIY banks with a good BMS would allow for such discharge rates, but I can't see how or why you'd want to discharge that much in a B van.