A 12V solar battery is considered fully charged at 12. 8 volts, and it should not be allowed to drop below 11. The voltage of energy storage battery cabinets typically ranges from 12V to 800V, influenced by application requirements, technology used, and the configuration of battery cells. Basically, you have three main choices— 12 volts, 24 volts, or 48 volts. So, which one is right for your power requirements and the needs of your solar power system? If. Common Voltage Options: Solar batteries typically come in three common voltages: 12V (for small systems), 24V (for mid-sized systems), and 48V (for larger installations). It directly affects inverter compatibility, wiring efficiency, and system scalability. Voltage, also known as electromotive force, is a quantitative expression of the potential of a battery.