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I have a MacBook Pro, and I want to keep its battery healthy for as long as possible.

I've heard many "myths" about all these, one of them being that the battery will get "hurt" if I plug in the MacBook when its battery is high enough (higher than 75%), let it until it reach 100%, then unplug it.

Is that true? Also, is it good to let the MacBook battery go to 0 then plug it?

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  • I can recommend the FruitJuice app for this. It keeps track of how your battery has been charging and discharging and it prompts you to plug in or unplug your laptop as appropriate.
    – bdesham
    Commented May 15, 2014 at 22:08
  • Does your Macbook Pro have a builtin battery, or 'user removable'?
    – user78503
    Commented May 30, 2014 at 15:03

2 Answers 2

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You are right lots of myths.

and more info this "kb/ht1446"

Apple Portables: Calibrating your computer's battery for best performance

The battery has an internal microprocessor that provides an estimate of the amount of energy in the battery as it charges and discharges. The battery needs to be recalibrated from time to time to keep the onscreen battery time and percent display accurate and to keep the battery operating at maximum efficiency. You should perform this procedure when you first use your computer and then every few months after that. If you normally leave your Apple portable computer connected to AC power and very rarely use it on battery power you may want to perform this process once a month.

  • Portables with built-in batteries (aka MacBook Air)

Current Apple portable computer batteries are pre-calibrated and do not require the calibration procedure outlined in this article.

In summary:

The battery has no memory effect & can be charged whenever you like. You can't overcharge it, & charging automatically stops when your battery is full. The two biggest killers of Lithium batteries are heat & frequent full discharge/recharge cycles. For calibration reasons (to make your battery status indicator accurate) you can discard but not less than 20% once in a few months.

Best way to prolong the life is to keep it as cool as possible. That might mean do not take your lap top in your bed, do not keep it in the sun, ect.

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  • 3
    Can you please edit your answer to quote some of the recommendations in case the page gets moved and the link doesn't work? Thanks! Commented May 15, 2014 at 22:04
  • @AnnonomusPenguin Apple usually does not do that, but see the KB # so you can find it at any time.
    – Ruskes
    Commented May 15, 2014 at 22:44
  • @Buscar웃 - Apple do move pages
    – mmmmmm
    Commented May 15, 2014 at 22:56
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    Lith-ion batteries in newer models do not need to be calibrated and it can actually damage the battery to do so.
    – njboot
    Commented May 30, 2014 at 11:56
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    "Portables With Built-in Batteries:Current Apple portable computer batteries are pre-calibrated and do not require the calibration procedure outlined in this support article" support.apple.com/kb/ht1490
    – njboot
    Commented May 30, 2014 at 13:46
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I can only offer my personal experience on this, but I strongly believe that constantly leaving the battery at full charge (i.e., always using the laptop plugged in), in conjunction with heat, is detrimental to the battery's life. A lithium-ion or -polymer battery needs to be used--neither left at full charge or completely discharged for too long. So, in addition to the recommendations in the KB article, I would recommend that you not keep the laptop running off the AC adapter if the battery is fully charged.

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  • Mac batteries stop charging at 100%, and run off of AC power. How would that affect the battery's life in any way? Additionally, unplugging your Mac would cause more cycles to be used, shortening the battery life.
    – Oion Akif
    Commented Nov 6, 2017 at 0:40

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