Toshiba Satellite C875D - Manual (Page 83)

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.
Whether you enable Sleep Mode, which can conserve battery power if
you are frequently turning the computer off and on.
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.
Whether you enable Sleep and Charge function.
The condition of the battery terminals - you should always ensure the
terminals stay clean by wiping them with a clean dry cloth before
installing the battery pack.
Batteries exhausted time
When you turn off the power of your computer with batteries fully charged,
the batteries will be exhausted within the following approximate period.
Battery type Sleep Mode Shut Down Mode
Battery pack
(24Wh, 3 cell) about 1.9 days about 2.9 months
Battery pack
(48Wh, 6 cell) about 3.7 days about 5.8 months
Battery pack
(66Wh, 6 cell high
capacity) about 5.1 days about 8 months
Extending battery life
To maximize the life of your battery packs:
At least once a month, disconnect the computer from a power source
and operate it on battery power until the battery pack fully discharges.
Before doing so, follow the steps as detailed below.
1. Turn off the computer's power.
2. Disconnect the AC adaptor and turn on the computer's power - if it
does not turn on then go to Step 4.
3. Operate the computer on battery power for five minutes. If you find
that the battery pack has at least five minutes of operating time,
continue operating until the battery pack is fully discharged, however, if
the DC IN/Battery indicator flashes or there is some other warning to
indicate a low battery condition, go to Step 4.
User's Manual 4-27