Chosen Solution
I’m running Mohave 10.14 OS on a mid 2012 15” MacBook Pro unibody. I’ve upgraded my RAM and HD to an SSD and added a new battery in March 2021. I’m within a year of the installation of this latest battery and I’m only getting 6 hours from it. Is this normal? I’m reading email messages and news articles and have already lost 55% of my charge within 3 hours. Apple has taken away my ability to run command D for diagnostics. I have several tabs opened in Safari and have several apps up but not using. The Activity Monitor jumps around so much I’m not sure if one app is hogging the resources, Mail and Safari Networking seem to have the biggest numbers, 400+ MBs.
Well this batteries health is not very good! As an example my battery in my 2012 15” system looks like this:
You do need to charge your battery and look at how you are using your system. Are you running the system down fully than charging? If you are that will wear the battery out quicker. Instead when the battery is around one third plug it in. Calibration is really only needed with a fresh battery and only if you are what I call a road warrior who needs to travel. If not its not really needed as over time the system will learn the minimum and maximum levels.
Did you ever properly calibrate the battery after installing it? Where did you purchase the battery from? Apple MacBook Battery Calibration Charge it to 100%, and then keep charging it for at least 2 more hours. Then, unplug and use it normally to drain the battery. When you see the low battery warning, save your work, and keep your laptop on until it goes to sleep due to low battery. Wait at least 5 hours, then charge your laptop uninterrupted to 100%.