Antutu tester is a free app for Android that lets you check the battery performance this tool has various other features like Battery test,LCD test,System information etc
Download the app from the above link and click battery test
Click on battery test and hit start ,make sure your battery is above 20% to begin the test
After click start test Let the phone run for several hours, through the
consumption of battery power to
calculate your score.
Get the results and compare them with your friend’s or other phones.
System information gives info for CPU, GPU, Memory, SD Card,
Screen, WiFi, GPS.