Using the powercfg command, Windows can create detailed reports on
the built-in battery in your Windows 8 notebook or tablet. In addition
to the maximum operation time in battery mode, you'll also learn how
healthy the battery is. Even better, checking the status of your battery
is really easy!
1. Start Command Prompt and choose to Run as Administrator
2. Type in the command 'powercfg /batteryreport' and hit Enter
3. Load up the report in a browser
The default option for saving the Powercfg report is to save it as an HTML file in the
C:\ folder. Double-click on the file called
battery-report.html, and open the report in your browser.
Useful information in the battery report.
First, you'll see a brief summary of the important information about your computer and the integrated battery. The
Design Capacity value is the value provided by the manufacturer relating to the maximum capacity of an unused battery. Full
Charge Capacity displays the current maximum capacity of a fully charged battery.
On the basis of these values, you'll quickly be able to see how
much power is left in your battery. If you're buying a new one, you can
easily discover damaged batteries and, if necessary, exchange the unit.
Further down in the report, you can find information regarding all
the previous charging cycles, in chronological order. If you re-install
Windows, you will lose all of the data previously collected.
Using this and other data, 'powercfg' estimates the expected
remaining battery life. This value, however, is never exact because it
depends on how the device is being used; tasks that involve heavy use of
the processor, Wi-Fi use and turning up the screen brightness, all mean
that the battery won't last as long.
The more data that Windows has at its disposal, the more accurately
it can estimate battery capacity. This value can then be queried at any
time via the system tray icon.
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