SOK LiFePO4 Batteries
SOK Battery makes LiFePO4 (lithium iron phosphate) deep-cycle batteries for RV, van and boat house banks. Most models have a Bluetooth BMS you can check from your phone, the heated models take a charge in freezing weather, and several have a removable cover so the BMS or cells can be replaced instead of the whole battery.
SOK batteries ship to the lower 48 states.