Solar cells, which are usually made of silicon to absorb sunlight, capture the sun energy and convert it directly into DC currents by photovoltaic effect, and the produced direct currents lead to BOS of PV system through wires.

Solar Cell Module : Individual cells are combined into a Module
Solar Cell Array : Individual modules are combined into an Array

A charge controller is to prevent over-charging, which results in out -gassing of the battery, as well as keeping electrical storage in the battery from discharging to the solar modules at night

A rechargeable battery stores direct currents generated from the solar modules and discharge the DC currents as needed usually at night

An inverter converts the DC currents stored in the battery into usable AC current which is the most usual type used by most home and business appliances, and an inverter has a circuit breaker for over-discharge.