Watt-hour
Also: Wh, energy capacity
An energy unit equal to one watt sustained for one hour.
For an approximately constant nominal battery voltage, energy is estimated as voltage times ampere-hours, with discharge and conversion limits stated separately.
- Units
- Wh; 1 Wh = 3600 J
- Formula
E ≈ V_nominal × capacity_Ah
Example A 3.7 V, 2 Ah cell is approximately 7.4 Wh nominal.
Common misconception Watt-hours are energy, not instantaneous power or guaranteed usable output.