The battery time indicates the approximate time how long your portable computer will be able to operate after it has been disconnected from the electricity supply when the battery is fully charged.
The battery time depends on the configuration, performed operations and other factors. This indicator usually is based upon the testing results. The lithium batteries built-in modern portable computers usually provide the operation time of 3 to 5 hours and this time depends on the use and configuration of the computer. The maximum battery capacity reduces the time of use of the portable computer. Currently lithium batteries are used in computers and they replaced nickel batteries. It has to be taken into account that the lifetime of portable computer batteries is limited. The capacity decreases with time and it is necessary to replace the battery.
*The battery time may decrease depending on the loading of the portable computer during the time when the battery is used as the power supply to the computer.