Battery over-discharge protection with dead-bus recovery

A battery and photovoltaic based power system comprises a power bus, a battery, a battery circuit, a photovoltaic circuit, a photovoltaic diode, and a switch control. The power bus comprises a supply side and a return side. The battery is coupled to the return side. The battery circuit couples the battery to the supply side and comprises a switch and a diode in parallel with the switch. The photovoltaic circuit is coupled to the return side and comprises a photovoltaic array and a second switch in parallel with the photovoltaic array. The second switch opens if the supply side is substantially depleted of power. The photovoltaic diode is connected in series with the photovoltaic circuit, with a cathode of the photovoltaic diode coupled to the supply side. The switch control monitors one or more battery parameters and controls the switch based on the one or more battery parameters.