Toshiba Tecra A40-J User Manual page 60

Maximizing battery operating time
The usefulness of a battery depends on how long it can supply power on a
single charge, while how long the charge lasts in a battery depends on:
Battery pack exhausted time
When you turn off the power of your computer with the battery pack fully
charged, the battery pack will exhaust within the following approximate
period.
Battery type
Battery pack
(53 Wh, 4 cell)
Be aware that the battery pack exhausted time is affected if there are any
external devices connected.
User's Manual
With repeated discharges and recharges, the battery capacity will
gradually decrease. In view of this, it is noted that an often used, older
battery will not operate for as long as a new battery even when both
are fully charged.
Processor speed
Screen brightness
Internal storage drive power off period
How often and for how long you use the internal storage drive and
external disk drives, for example, optical disc
How much charge the battery contained to begin with
How you use optional devices, such as a USB device, to which the
battery supplies power
Where you store your programs and data
Whether you close the display panel when you are not using the
keyboard - closing the display saves power.
The environmental temperature - operating time decreases at low
temperatures.
System Sleep Mode
System Hibernation Mode
Display power off period
Whether you enable Sleep Mode, which can conserve battery power if
you are frequently turning the computer off and on.
Sleep Mode
about 6 days
Shut Down Mode
about 20 days
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