I have a early 2011 13" macbook pro. A week or 2 ago the battery gave me about 7 hours, now it only gives me about 3 and a half hours? Is there something wrong with my battery?
Likely not. Battery life will depend on your usage. Running CPU/GPU intensive tasks will decrease battery life. As
simsaladimbamba suggested, try to pinpoint what's using your CPU (and how much). Also, you may want to check your battery status by opening
System Profiler (System Information in Lion) and selecting the
Power tab under
Hardware then see what your battery's Full Charge capacity is vs Design Capacity; you can also use
CoconutBattery to do that.
It looks like anything, could it be that i have upgraded to lion
It could be. After upgrading and/or reinstalling Mac OS, finder will take some time to re-index your Hard Drive, which will require quite a bit of system resources, thus decreasing battery life for the time being. As always in a case of OS reinstall/upgrade, the system will need time to "settle down". Under processes, look for
mdworker - if it's using quite a bit of CPU, that's Finder indexing.
what does calibrating battery do? i have 2011 13" base line MBP and the battery last like 4 hours which sucks when compared to the 2010 15" MBP which last 7 hours!! actually, the 2010 MBP fluctuates between 6 ad 8 hours... is this normal?
Calibrating a battery corrects the system's reading of the actual remaining battery capacity.
The 2010 and 2011 models have the exact same battery of the exact same capacity. The 2011 models did ditch a separate GPU chip for an integrated one but the overall TDP remains the same, so is battery consumption, meaning that the 2010 and the 2011 models should have [roughly] the same battery lives. That being said, battery life will depend on what you're doing on the computer. If you are concerned about your battery life, download and install
CoconutBattery.
As a point of reference, here's my battery info (2011 Macbook Pro, Core i5; around 4 months old)