Would you like to know how well your Microsoft Surface's battery performs?  Or like the ability to show exactly how long your specific Surface's battery is rated to last? Did you know that no two batteries have the exact same power capacity and that full charge degrades over time?

If these questions interest you, here's a neat trick.

  1. At an elevated Command Prompt…

  1. …run the following two commands on separate lines…
  1. powercfg /batteryreport /output %tmp%\battery-report.html
  2.  
  3. explorer %tmp%\battery-report.html

This set of commands runs the Windows 8 powercfg utility to retrieve battery information, outputs the retrieved data to a battery-report.html file in the %tmp% directory, and then opens the battery-report.html file in the system's default browser.

The resulting report details the following:

  • Basic computer inventory
  • Installed battery information
  • Power states over the previous 3 days
  • Battery drains over the previous 3 days
  • History of system usage on AC and on battery
  • Charge capacity history of the system's batteries
  • Battery life estimates based on observed drains
  • Current estimate of battery life based on all observed drains since OS install

It’s a slick report, but also extremely valuable to show battery life degradation over time.

P.S. This method works for any device with a battery running Windows 8 of Windows 7.