Scott Watermasysk

Still Learning to Code

Calibrating a MBP Battery

I recently noticed the battery on my 12+ month old MBP was only lasting about 2 hours.

A single charge on this model is supposed to last about 7 hours. I expected some decline after a year, but a drop off to 2 hours seemed off. In addition, unlike previous battery declines/issues the time seemed accurate. In other words, it was not reporting more time and then quickly draining.

A quick look around Google led me to the following Apple support document Calibrating your computer’s battery for best performance

Quick Steps:

  1. Completely charge your battery (and keep it charged for 2 hours).
  2. Unplug the power adapter and allow the battery to completely drain. You can use your computer during this time.
  3. Allow it to sit powerless for at least 5 hours.
  4. Recharge the battery.

I was skeptical, but after completing these steps, my full charge estimate went from about 2 hours to almost 5 hours.

Tip: Here is a great tool for MacBook users to monitor their battery’s health – Battery Health Monitor.

Update: It is now appears to be estimating the battery time at about 4 hours instead of 5. Not horrible, but not as good as I originally was seeing. I will report back of the decline continues.