What does a lithium-ion battery do? Cells in a battery store, transform, and conduct energy.

A lithium-ion battery and circuit transform electrochemical energy into electrical energy and transmit that energy as a current to a device, which is known in a circuit as a “load.”

The opposite reaction also occurs: When a battery is being charged, the movement of electrons and ions transforms electrical energy into electrochemical energy. The battery stores this electrochemical energy.