Chosen Solution
A few months ago, I replaced by battery (from a third-party seller, not ifixit). It was working great, until recently, when it ran out, then was plugged in overnight and got stuck at 55%. Unplugging it and plugging it back in resulted in it very slowly charging up to 60%. It is stuck at 52% right now. I’ve tried a SMC reset, I’ve tried calibrating by fully discharging, and I’ve tried reseating the connector. Other information:
The computer doesn’t shut down gracefully when the battery runs out; it always hard powers off around 5-10%. This has been an issue since before I replaced the battery.
Well the Battery is showing its age ;-{ You have two things coming at you age and cycles! The age of your battery is now over seven years old (2015 - 2022) for a battery which lifespan is about five years. The batteries chemistry breaks down. The cycle count is 138 currently, this battery has an expected cycle of 1,000 cycles (+/- 10 %) Determine battery cycle count for Mac notebooks So I would say its already on borrowed time! Time for a fresh battery. You should be able to get at least 5 more years if you give it the needed TLC.. You might try resetting the SMC How to reset the SMC of your Mac but that will only buy you so much. Sorry ;-{ Here’s the needed part MacBook Pro 15" Retina (Mid 2015) Battery and here’s the guide MacBook Pro 15" Retina Display Mid 2015 Battery Replacement
