The best performance period of a Macbook battery is up to its first 300 charge discharge cycles. after that, the battery capacity will gradually decrease and also the backup time also will decrease. You can check your Battery cycle count by- Go to “Spotlight” and search for “System Information” and under the “Hardware”, select “Power” and on the right panel you can find your macbook battery cycle count.
Mine is : Cycle Count: 359
Fixing the Battery is not charging Issue
If your Magsafe power adapter working properly, and your wall socket and power supply is good, Then you can try reseting the SMC (System Management Controller) to resolve some of these unusual system behaviours. You can safely try reseting the MSC, it will not wipe and data from your MAC.
- Turn off your macbook
- Plug the Magsafe power adapter
- In the keyboard press (left) Shift+Control+Option and then press the Power button
- Release all the 4 together
Now the SMC console will reset and you can check the macbook battery charging status. If you still having the Battery is not charging problem, then bring your macbook to a authorised Apple service centre.
Tip: Always operate your Macbook in recommended temperature , and Calibrate battery periodically.