Pranay Bhowmick ,a regular 551 blog follower and friend ,presented me with his study of battery life of Galaxy 551 .This is a highly accurate and comprehensive report
Definition and explanation of Standard test conditions: No Wifi, 3G , GPS 2G internet (EDGE) ON and Background Data sync ON Background apps: YahooMail , Gmail , SMSBackup , Facebook , Go SMS Pro , Advanced Task Manager ,CPU Tuner , 3G WatchDog , MessageEase , ADW Launcher . Advanced Task Manager feature > auto-kill at every screen on/off< is ON with all apps mentioned above in the Ignore list (Not to kill apps) Screen Brightness 10% and Screen timeout 15 seconds , NO live wallpaper Usage under standard test conditions: (Read : Moderate use) 1:45 hours of earphone music using PowerAMP and screen being off for 60% of this time 1:30 hours of internet using mostly Opera Mini and Facebook (others being WikiMobile, Stock browser, YMail , Market) 1hour of gaming (30mins of Angry Birds, 25minutes of Bubble Buster , 5 min of iRunner) 22 minutes of video playback using stock video player (with earphones) Around 120 incoming + 120 outgoing text msgs Notification for incoming msgs : Only vibration , Vibration pattern : 200,100,200,100 (Read : two mild vibrations) 90% text msgs typed using MessageEase i.e only 10% using physical keyboard Around 30minutes of miscellaneous (playing around with the phone doing nothing) No calls. I have my SE k750i to make and receive calls. Key Findings of the Study: What drained battery most? Gaming(as expected): 30minutes of Angry Birds and around 18% of battery gone!! 25minutes of Bubble Buster and 5% of battery gone! Video Playback: 22minutes = 7% battery drop What else is important? Physical Keyboard uses more battery because of the backlight. ( There is not option to turn off backlight) . Standby battery usage varies between 2-5% of battery consumption per hour. Conclusions: I Must confess that the outcome exceeded my expectations. I got exactly 21hours (100% to 0% battery) 4hours more than my expectation of 16 hours. ! But practically, u don’t wait for battery to become zero to connect your AC power. So we can easily say that 20 hours is the standard battery life with moderate usage.
This is the study by him
I would like to add something from my previous study
3G knocks 5 hours off the battery
WiFi knocks 4 p.c per hour
Increasing screen brightness to 50 p.c knocks one hour off
Disabling Data connection adds 18 hours
Using Google Maps – Latitude at once knocks 3-4 p.c + 1 p.c per 10 minutes
Solo-GPS knocks 1.pc per five minutes
One call of 150-170 seconds knocks off 2-3 p.c battery
At total minimum proc stress (122Mhz-90p.c) The phone lasts 35 hours
Keeping one mail app like K-9 increases battery slightly
Disabling sync of twitter and facebook account is recommended .(I dont use both ,no comments)
Tower defense games consume less battery then normal games.
Talking tom cat consumes 10 p.c battery in half hour.
Hope this study helps guys