These days if I’m going to a longer meeting I take my power cord as a safeguard. My MacBook Pro’s more than a year old now, and while the battery will commonly last a couple of hours I don’t always trust it. I do know that if I play tracks from iTunes or use Parallels while on battery the Mac runs out of juice pretty quickly.
I’d totally forgotten about periodically freshening up the battery by recalibrating, but Debbie at Splash of Style has provided a good reminder: MacBook Pro Battery Calibration:
I purchased my MacBook Pro on June 11; I calibrated the battery on June 13, and it really seemed to make a difference. I used Coconut Battery software to track my battery capacity on several occasions, …
MacBook Pro battery calibration is different from PowerBook calibration, so please read over the instructions at Apple.com very carefully. Basically, you allow the battery to run down until the laptop is forced into sleep mode. Allow it to sleep for at least 5 hours, or you can opt to shut off the laptop.
After five hours, the MacBook Pro can be plugged in and the battery can will start to charge. Keep it plugged in until it is fully charged.
… In Apple’s documents, it does suggest to calibrate every two months or so. …
I just checked with coconutBattery, and find that my battery’s at 96% charge (after being plugged in and asleep all night). The current capacity is 3142 mAh: 57% of the original capacity of 5500 mAh. I’m intrigued by the age of my MacBook Pro as shown in coconutBattery: 24,440 months. Hmmmm.
Apologies for the size of this screenshot — I’m experimenting with Skitch.