An energy unit where 1 watt-hour = 3,600 joules = 1 watt × 1 hour. Widely used for small battery capacities (e.g., smartphone battery: 10 Wh), portable power stations, and UPS systems. A common unit in consumer electronics and energy management in China and globally, and equal to one-thousandth of a kilowatt-hour (kWh).

An energy unit where 1 watt-hour = 3,600 joules = 1 watt × 1 hour. Widely used for small battery capacities (e.g., smartphone battery: 10 Wh), portable power stations, and UPS systems. A common unit in consumer electronics and energy management in China and globally, and equal to one-thousandth of a kilowatt-hour (kWh).