Fixing Snow Leopard Unibody MacBook Pro Battery Life Problems

Ever since I upgraded the OS of my Early 2009 13″ MBP to Snow Leopard, I have a problem with the notebook’s battery life. When I was using Leopard, the battery could last very long, so long that I was used to working without connecting the notebook with a power source. I also remember that the Time indicator for the battery used to estimate about 7 hours or so of battery life at 100%, although it occasionally fell to 3 or 4 hours on heavy usage. But now, at 100% it would only show about 5 hours max.

For some time I used to think that this was probably due to 64-bit architecture change that caused the notebook to use more power. But the longer I used the notebook in this condition, the more I worry about the battery. According to Apple, the new battery technology in unibody Macs are supposed to last for 1000 charge cycles, about 3 years of normal usage. The battery problem means that I am using more cycles than it is supposed to be for a given time, which increases the possibility of the battery having degraded performance before the 3-years mark.

So I googled around a bit, and found out that other people are also experiencing the same problem. The solution to this problem is to do the following :

1. Reset the PRAM.
2. Reset the SMC.
3. Recalibrate the battery.

I did all three and the problem is now fixed, I can now see the 6+ hours battery life indicator on 99% again .

Horray!

EDIT : I am conducting a battery test to see the actual performance of the MBP’s battery here.