Note 1 to entry: The “nominal energy capacity” should not be confused with the “capacity” (used for cells, batteries, capacitors, etc.), which is an electric charge, usually expressed in coulomb (C) or ampere hours (Ah) (see IEV 482-03-14).

Note 2 to entry: Joule (J) is the SI coherent derived unit of the nominal energy capacity; other units can be chosen for convenience as well (e.g. kWh, MWh).

Note 3 to entry: The definition has been drafted along the same lines as that in IEC 60050-826:2004, 826­-11­-01.