Computer shuts off when battery at 79%
I just got a used Macbook Pro 13" 2011 and the battery checks out as okay, but I'm having a problem with the computer shutting down, on battery, when battery hits 79%. I have retested it after the first time, and it again shut down at exactly 79%.
It runs down normally from 100%, then suddenly shuts down.
I can't reboot without using power cable. When I boot up with power cable, the battery shows 79% full.
Coconut Battery shows:
Full Charge Capacity = 5062 mAh
Design Capacity = 5770 mAh
87.7%
Manufacture date in 2013
Cycle Count = 4
Battery status = Good
Battery temperature = 27.3 degrees C
Strange stuff:
1) The CYCLE COUNT is a bit strange. Only 4. Though it did go from 3, when the computer arrived, to 4 after my first charge.
2) The computer arrived with Sierra installed, but I had some problems with the battery. When I ran the battery down and the computer shut off, when I rebooted the battery icon was SERVICE BATTERY, and the Full Charge Capacity was down to 2300.
3) The battery is really SLOW to charge. I'm recharging now and it's taken 1 hour to go from 79% to 85%. It shows 3:30 until fully charged, from 85%.
I have since installed El Capitan, and the battery reports are back to normal.
But I still have the shutdown problem.