Most modern charge controllers incorporate maximum power point tracking (MPPT), which optimizes the Photovoltaic Panel array’s output,

increasing the energy it produces. Some battery based charge controllers also include a low-voltage disconnect that prevents over discharging,

which can permanently damage the battery bank. A charge controller’s primary function is to protect your battery bank from overcharging. It does

this by monitoring the battery bank. When the bank is fully charged, the controller interrupts the flow of electricity from the PV panels. Batteries

are expensive and pretty particular about how they like to be treated. To maximize their life span, you’ll definitely want to avoid overcharging or

undercharging them.