Macbook Battery Calibration - how empty does the battery need to be before charging

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Level 1

19 points

Macbook Battery Calibration - how empty does the battery need to be before charging

Hi all - i have a 2015 macbook pro 13 inch - at 300 cycles it is only showing 68% of its original battery which i think is poor.

I have been trying to recalibrate - instructions say to drain and leave for 5 hours before starting to charge it again - however even after 20 hours my laptop has enough charge to show the 'charge' symbol when i press the on key.

My question is can i start charging now or do i have to make sure there is zero power left in the battery before i start (i.e. not enough to even show the charge symbol on screen)

thanks

(ps i have tried SMC already but no change)

Posted on Dec 7, 2019 1:41 PM

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Answer 1

leroydouglas

Level 10

203,500 points

Dec 7, 2019 1:59 PM in response to Damien Kelly

Those are very old instructions not for the newer batteries.

What is the condition of your battery? Anything but Normal needs serviced.

Hold the option key and click the Battery icon in the upper right menu bar.

About Mac notebook batteries - Apple Support

https://support.apple.com/en-us/HT204054

Determine battery cycle count for Mac notebooks - Apple Support

https://support.apple.com/en-us/HT201585

Batteries - Maximizing Performance - Apple

https://www.apple.com/batteries/maximizing-performance/ 

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Answer 2

y_p_w

Level 6

17,804 points

Dec 7, 2019 2:40 PM in response to Damien Kelly

What it needs is a new battery. As long as the condition of the keyboard and top case is reasonable, Apple will do the service for $199 plus tax in the US. Apple does it as a complete swap of the top case. The exchanged part will receive a new battery and be refurbished where it can be used for a battery swap or a top case replacement. If the current top case has issues, they'll replace it at price for repair of a top case, but that will include a new battery.

Apple hasn't recommended any kind of "battery calibration" since before the Unibody MacBook Pro came out. That's about the time when the nominal rating for their lithium rechargeable batteries went from 300 to 1000 cycles. However, there's no guarantee about that performance, and lithium rechargeable batteries inherently decline with age anyways.

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Answer 3

Damien Kelly Author

Level 1

19 points

Dec 7, 2019 2:18 PM in response to leroydouglas

thanks very much for your reply - it says needs a service - i bought it this way fro0m a friend who had not used it in a few months - so on rebooting it has been saying service battery (it did not say this previously

I was hoping recalibration might removed this 'service' warning.

Attached is a picture taken before it was fully drained.

Could you recommend any other solutions if calibration is not warranted? Or is calibration still worth trying....

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