A milliampere hour (mAh) is 1000th of an ampere hour ( Ah ). Both measures are commonly used to describe the energy charge that a battery will hold and how long a device will run before the battery needs recharging.

For example, an IBM Thinkpad 365 with an Nickel-Metal Hydride 9.6 voltage battery that is stated to provide a charge of 2800 mAh offers from 2.5 to 5 hours of battery use without recharge.

24 Mar 2011