Lithium batteries are an assembly composed of many cells, like lead-acid batteries and many other battery types. Lead acid batteries have a nominal voltage of 2V/cell, whereas lithium battery cells have a nominal voltage of 3.2V. Therefore, to achieve a 12V battery you'll typically have four cells connected in a series. This will make the nominal voltage of a LiFePO4 12.8V. Eight cells connected in a series make a 24V battery with a nominal voltage of 25.6V and sixteen cells connected in a series make a 48V battery with a nominal voltage of 51.2V. These voltages work very well with your typical 12V, 24V, and 48V inverters.