If you are running windows 7 and want to extract more juice out of your battery or if you are having low battery back then there is a hidden report in windows 7 which will help you out to sort out the issues and problem so that you can get more out of your laptop battery.
Before generating this report you computer should be in an idle sate exit all running applications.
To run and generate this report first you will have to run the command prompt as administrator.
At command prompt type the following
Now it will run the tool which will examine your computer and when it gets over you can see a message indicating number of errors, warning and information messages found.powercfg -ENERGY
Now you will have to type following at command prompt to view the HTML report which was generated in earlier step.
Please note if you don't have Internet explorer as your default explorer then it may not display the report, just copy the link of the report which came in your default browser and paste it to the address bar of Internet explorer and click enter.energy-report.html
In that report all the Errors will be in pink box, warnings will be in yellow box and information's will be white.
Rectifying the errors and warnings will give you a better battery backup and lifetime.