In a lead-acid cell each electron sent to the anode is given 2 eV of energy. What emf does one such cell provide?

1. Voltage is defined as electrical potential energy divided by charge. 2. One electron volt is the energy a single electron receives from a potential difference of 1 V. 3. Each electron here receives 2 eV, so it has been carried through a potential difference of 2 V. 4. The cell emf is therefore 2.0 V, fixed by the energy of the chemical reaction rather than by the size of the cell. 5. 12.0 V is the emf of a complete car battery, which stacks six such cells in series. 6. 6.0 V would call for three cells in series, and 0.50 V is closer to the output of a single solar cell. _Source: OpenStax College Physics (CC BY 4.0), Ch 21 "Circuits and DC Instruments", section 21.2 Electromotive Force: Terminal Voltage_