Open-circuit voltage (abbreviated as OCV or VOC ) is the difference of electrical potential between two terminals of a device when disconnected from any circuit. There is no external load connected. No external electric current flows between the terminals. It is sometimes given the symbol Voc. In network analysis this voltage is also known as the Thévenin voltage.
The open-circuit voltages of batteries and solar cells are often quoted under particular conditions (state-of-charge, illumination, temperature, etc.).