I want my battery to remain healthy. I used to charge it full then remove the charger after it's done, then put it back on when it goes down to 10% .. However this is becoming hectic and I was wondering if I can keep it plugged in the whole day and probably remove just an hour or so before going to sleep.

What is the best way to charge and discharge my Retina Macbook Pro while keeping the battery healthy ?


Quick Answer

Modern batteries, including the ones Apple has used for over a decade, don't need the type of "conditioning" you're talking about.

As a rule of thumb, when you're near an power adapter, plug in. If you're not near one, work off battery power.

There's just one exception to this rule: don't leave your Mac plugged in for long periods at a time, say, over a week. The battery needs to exercise, and if it's plugged in for a really long time, it might "atrophy."

More Details

If you tend to leave your computer plugged in all the time (for example, if you leave it on a desk all the time), get in the habit of unplugging it every weekend. It doesn't need to drain to 0% each weekend, or even close to it. Along this same line, if you're leaving your computer along for over a week, just leave it unplugged.

The one-week timeframe is actually a bit over-cautious, and no harm is likely to occur even if you left it plugged in for two weeks. (Apple's batteries are the best on the market as far as taking care themselves.)


  • Agree: Usually the conditioning is required for Ni-MH batteries (not often used these days). Not required for Lithium-ion. – sjbx Oct 6 '12 at 18:35
  • So even if the power cord is lit green, its okay to leave it plugged, up to 1 week straight? – user1539064 Feb 16 '13 at 0:28

Its absolutely ok to leave it plugged on. The MBP will run, using the power from the charger directly and at the same time keep the batteries on trickle charge ( the trickle charging processes starts right from 80% upwards) However a deep discharge/charge cycle is advised only every 6 months.

  • 1
    Can you source your information ? – Render Mar 19 '13 at 17:20
  • How does one perform a deep discharge on the new unibody Mac batteries? Apple's information recommends normal charge / discharge once a month. apple.com/batteries/notebooks.html – bmike Mar 19 '13 at 18:20

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