Real-world battery runs are generally about half of those quoted by the manufacturer, so unless you've adjusted the settings for extreme power conservation (screen on dimmest, CPU set as slow as you can, etc.) - what you're seeing is just about normal.  
Kindly advise I just bought Dell 5620 yesterday and in specs it was written 5,6 hours battery life but in real life maximum it provides in between 2 to 3 hours. compelled to reduce resolution so battery can perform better but still poor performance. i bought this laptop it does have 55watth battery and 65-watt charger but I am still very disappointed by the performance. Is this the manufacturing issue or by default company made this? i am just doing normal browsing and MS Office work not even PowerPoint. #Dell Professionals
Poor battery life Dell 5620