Any way to keep Macbook Pro from charging when plugged into power?

Discussion in 'MacBook Pro' started by zorinlynx, Jan 3, 2014.

  1. zorinlynx macrumors 603


    May 31, 2007
    Florida, USA
    Here's the story...

    I use my rMBP 13" (Late 2013) at my desk at work all day every day, plugged into power. During the week I don't use the MBP on battery very much, so it ends up charging every morning from 99% back to 100%.

    I know for a fact that topping off the battery every day like this isn't good for it. I'd rather not charge it back up to 100% every single day! Is there any "secret" command that can prevent charging the battery if it's not below a certain threshold? I'd love to set that threshold to 90% or so.
  2. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    There is no such command, but don't worry about it. If you are using it occasionally on battery power, that is enough exercise for the battery.

    There actually is circuitry built in that stops it from hitting 100% if you have only used it on battery a short time.

    Give this link a look.
  3. MacDawg macrumors Core


    Mar 20, 2004
    "Between the Hedges"
    Never hurt the battery on my MBA, nor does it hurt the battery on my MBP as far as I can tell
    Both are doing well, and I use them plugged in all the time except when driving from home to work and back, or I am on the road traveling
  4. zipa macrumors 65816

    Feb 19, 2010
    Your "facts" are utterly wrong, so keep calm and enjoy your macbook.
  5. drambuie macrumors 6502a

    Feb 16, 2010
    My 2010 MBP is 39 months old. I use it plugged in most of the time and rarely let the battery drop below 85%. Most times I recharge it at about 93% charge, and coconutBattery reports the battery at 99% health. I don't know about the rMBP charging characteristics, but the cMBP batteries won't start charging until the level drops below 95%.
  6. tymaster50 macrumors 68030


    Oct 3, 2012
    New Jersey
    i believe they changed it so now the battery won't go past 100% charge lol. Meaning you can leave it on the charger all day.
  7. zorinlynx thread starter macrumors 603


    May 31, 2007
    Florida, USA
    Actually, they're not.

    Being fully charged all the time reduces the lifetime of Lithium batteries. Batteries have the best longevity when kept around the 75% mark. It's not a huge difference, but when you're using a laptop with a non-replaceable battery, every bit counts!

    One good example: Electric cars based on lithium battery tech, like the Tesla, can be configured to not charge past a certain level to increase the life of the battery. You do partial charges when commuting, and only do the full charges when you're going on a longer trip where you need the range.

    I'd like to be able to do the same with my Macbook, though it seems to not be possible. Ah well.
  8. priitv8 macrumors 68040

    Jan 13, 2011
    You can take a look at Apple smart battery hacking (there's an article about it on the web).
    In a nutshell you'd be looking at programming the TI Gas Gauge that controls the battery. Said article was accompanied with a source code to try this out.
    But IMHO it's not worth the time and effort. Not to mention the risk to brick your battery for good.

Share This Page