Victron SmartSolar MPPT Charge Controller

This is the best solar charger controller for LiFePo (lithium) batteries, especially when using Victron equipment. Available in 30 or 50 amps. Use the 30 amp if you have less than 400 watts of solar panels and the 50 amp unit for 400+ watts. 

A solar charger gathers energy from your solar panels, and stores it in your batteries. Using the latest, fastest technology, SmartSolar maximizes this energy-harvest, driving it intelligently to achieve full charge in the shortest possible time. SmartSolar maintains battery health, extending its life.

The SmartSolar charge controller will even recharge a severely depleted battery. It can operate with a battery voltage as low as 0 Volts, provided the cells are not permanently sulphated or otherwise damaged.