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Watt Hour.

A Watt hour (Wh) is a unit of energy.

One watt hour is equivalent to 3600 joules.

Wh is an abbreviation often used on laptop batteries to indicate their capacity. The higher the Wh figure the higher the storage capacity and the longer it should be able to power a laptop.

An alternative unit which is often used is mAh (milliamp-hours). To convert from mAh to Wh use the formula:

Wh = mAh x volts / 1000

For more information see: