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Christine

I'm a geek with a love for all things tech. I'm also an online business consultant with expertise in SEO, SMM, and digital marketing strategies.

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15 Comments

  1. 1

    Jonathan Simon

    I usually just charge my laptop over night, and carry it around in sleep mode all day in my backpack. Run it down during class, charge it back up at night.

  2. 2

    Kasper Nielsen

    As far as I know (From Wikipedia/li-ion batteries), temperature is much more important to battery life. So just unplug the battery (if possible) when you know you are not going to use it for some time.
    Or throw it in the refrigerator plugged in for extended periods.

  3. 3

    Mike Soliman

    I found this website to be a pretty thorough resource on all things battery.

    http://www.batteryuniversity.com/parttwo-34.htm

  4. 4

    Mike Cerm

    The correct answer is: Yes, leaving your laptop plugged-in all the time will kill the battery. There is no definitive study that I can point to, but every article I’ve ever read concluded it to be true, and the overwhelming majority of anecdotal evidence from users of all brands report this to be the case.

    The best solution, however, is not to unplug. If you unplug, discharge, and plug back in, you’re adding unnecessary cycles. The best thing to do is to remove the battery when you’re not actively charging it, and stay plugged-in. (This is possible with all laptops, except for the newer MacBooks.)

  5. 5

    Mike Cerm

    Also, just to echo what Kasper said, batteries are sensitive to heat. That’s another reason not to leave your battery attached while it’s not in use, as the internals of laptops get pretty hot (100-150 degrees is typical), and batteries do best at room-temp (70 degrees) or cooler.

  6. 6

    AJ Robins

    Wikipedia (the references, actually) has decent info. To summarize (hopefully, I’ve remembered everything correctly):

    * For modern lithium-ion batteries, heat is likely to be the #1 cause of shortened laptop battery life (being next to high-temperature laptop parts is not really good). Heat is a killer; generally, the cooler the battery is kept (but not freezing or below), the longer the useful battery life.

    * Lithium-ion batteries like short discharge/charge cycles. Deep discharges aren’t good for the battery.

    * However, the battery meter circuitry does generally need a periodic deep discharge for calibration purposes (so that your battery meter reads correctly). Yes, this is at odds at “deep discharges” aren’t good for the battery, but this is an engineering tradeoff: do you want an accurate battery meter or not? In theory, doing it once a month shouldn’t affect the useful lifetime appreciably, which is why the vendors recommend that a deep discharge be done once a month or so.

    * Lithium-ion batteries don’t have memory.

    * Generally, lithium-ion batteries start degrading from the moment they’re made (due to oxidation, IIRC). Because of this, it may not make sense to buy a spare (to use when the current battery degrades).

    * Long-term storage should be with a partial, and not a full charge.

  7. 7

    AJ Robins

    Also, in case it’s not obvious: keeping the laptop plugged in and turned on all the time, keeps the battery warm/hot, which shortens the battery life. If you must keep the laptop plugged in all the time, turn off/suspend/hibernate the laptop.

  8. 8

    Claudio

    Look no further than my mac for proof (though more than one data point is usually recommended). Info from the CoconutBattery app:

    Battery-Load Cycles: 91
    Age of your Mac: 36 months
    Original Battery Capacity: 5500 mAh
    Current Battery Capacity: 1764 mAh (32%)

  9. 9

    mgseeley

    As a point of comparison with Claudio, I regularly unplug my MBP and use my battery down to the reserve power warning before plugging back in. her are my CoconutBattery stats:

    Battery-Load Cycles: 695
    Age of your Mac: 19 months
    Original Battery Capacity: 5600 mAh
    Current Battery Capacity: 2433 mAh (43%)

    So what does tell us? My battery is half as old as Claudio’s but I cycle it far more frequently. I have more life left in it but should it have more being newer, or less due to heavy cycling?

  10. 10

    Guillermo Esteves

    I keep my 14-month-old MacBook Pro plugged-in practically 24/7. Now it shuts down without warning at 60% charge (it doesn’t even go to sleep, it just dies) and the battery icon says “Service Battery.”

    There’s a chance it’s not related to keeping the laptop plugged-in all the time, but once I replace the battery I won’t be doing it any more.

  11. 11

    Himanshu Saluja

    I have this Lenovo 3000-Y500 for about 4 years now and it hasn’t shown much decline in battery prowess.

    I just make sure its plugged in only when it is on or has less charge.
    I unplug it when not in use and full battery.

  12. 12

    emailtoid.net/i/8b2d5e1c/…

    a mod on thinkpads.com forums suggested i let my 9cell drop to ~40%, then recharge. when on the dock i wait til it drops to 99 or 98%, then unplug, drain to 40% or so, then recharge. after 4 years of ownership and one battery, i’ve still got near full capacity. seems like a good tip for this type of battery.

  13. 13

    Nehal Patel

    My work laptops have always been continually charged since they are in a docking station all day – I work in a cube and connect 2 monitors, mouse, keyboard. as a result, my battery life eventually dwindles to about 15 minutes which turns my laptop into a workstation.

  14. 14

    Jeff Harbert

    Any rechargeable battery, in my experience, must be used pretty regularly or they won’t hold a decent charge. This is true of all the double-A’s I own, my 14.4v Makita, and my laptops. I try to get my laptop battery down to 10% or so at least once a month.

  15. 15

    svtcobra

    I have 3 HP laptops at home that are always plugged in except for the occasional trip out of the house. 2 are used for 6-10 hours a day. The third is turned on and used about once every 10 days and used for about an hour. They all have 6 cell batteries, all 18 to 24 months old. Using advice I received from an HP level 2 tech, I leave the batteries out all the time (when plugged in) and only insert the batteries once a month, at which time I switch to battery power and run them all down to 2%, and then fully recharge them. All 3 of the batteries are still running at 80 to 85 percent of their ‘new’ capacity, based on how long the machine actually runs before neeeding recharging. This compares with my previous HP laptops’ batteries that were left in the laptops all the time and were essentially useless by the time they were 24 months old. Just my 2 cents worth on my personal experience.

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