Ale47099

Q: Battery Questions

So I just got my new Macbook Air 11" (LOVE IT TO DEATH), and like most people, I'm very paranoid about having the computer and it's battery last as long as possible.

 

Two questions:

 

1) Say I get home from school, my batteries at around 60%. I then use the rest of the battery at home. Just before the battery runs out to 0%, I plug it in. The battery then reaches 100% again while I'm still using it.

 

Since I want to start with 100% the next morning, is it better to leave the charger plugged in for an hour or two more before I go to sleep and then turn it off and unplug it at 100%, or should I disconect the charger as soon as it hits 100%, use it a little more untill it gets to maybe around 85%, stop using it , and then an hour or so before going to sleep have it charge to 100% again and then turn it off and disconnect it before going to bed?

 

 

This also leads me to my second question:

 

2) Say I go to bed with it at 85%, I turn off the computer, but leaved it plugged in all night. Does leaving it plugged all night (7 hours or so) around 3 times a week harm the battery in contrast to making an effort to have the computer reach 100% before I go to sleep, turn it off, and not have it plugged in?

 

I know both are REALLY stupidly over paranoid questions and what not, but that's just me.

 

Any answers or general tips for making a long lasting battery would be greatly appreciated! Thanks!

MacBook Air, OS X Mavericks (10.9.3), April, 2014 model

Posted on Jun 5, 2014 7:58 PM

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Q: Battery Questions

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  • Helpful answers

  • by John Galt,Helpful

    John Galt John Galt Jun 5, 2014 8:06 PM in response to Ale47099
    Level 8 (48,515 points)
    Mac OS X
    Jun 5, 2014 8:06 PM in response to Ale47099

    Your MBA is designed to sleep before the battery reaches a depletion level that will affect its life. Don't leave it in that state for very long, and don't make it a habit to discharge it completely either.

     

    Charge it when it is convenient to do so, and don't obsess over this degree of detail. Apple designed your Mac to be used without such needless concern. Its battery will last for years, but it will eventually need to be replaced. Budget about 50 cents a week for battery depreciation and you will have more than enough saved to replace it when necessary.

  • by PlotinusVeritas,Solvedanswer

    PlotinusVeritas PlotinusVeritas Jun 5, 2014 9:46 PM in response to Ale47099
    Level 6 (14,806 points)
    Jun 5, 2014 9:46 PM in response to Ale47099

     

    Ale47099 wrote:

     

    Just before the battery runs out to 0%, I plug it in. The battery then reaches 100% again while I'm still using it.

     

     

    NEVER LET IT get even close to that, thats the fastest way to battery ruination.

     

    Lithium batteries despise deep discharges, period

     

    See RED below

    Ale47099 wrote:

     

    Does leaving it plugged all night (7 hours or so) around 3 times a week harm the battery in contrast to making an effort to have the computer reach 100% before I go to sleep, turn it off, and not have it plugged in?

     

    Dont do that often either,........

    See RED below

     

     

     

    Considerations for the long life of your Macbook Air. Handling and environmental care tips

     

     

    General consideration of your MacBook battery

    batts.jpg

    Contrary to popular myths about notebook batteries, there is protection circuitry in your Macbook and therefore you cannot ‘overcharge’ your notebook when plugged in and already fully charged.


    However if you do not plan on using your notebook for several hours, turn it off (plugged in or otherwise), since you do not want your Macbook ‘both always plugged in and in sleep mode’.

     

    Do not perform “battery calibration” on your current Macbook. There is no calibration of current Apple portable Macbooks with built-in batteries.


    A lot of battery experts call the use of Lithium-Ion cells the "80% Rule", meaning use 80% of the full charge or so, then recharge them for longer overall life. The main quantified damage done in the use of Lithium Ion batteries are instances where the internal notebook battery is “often drained very low”, this is bad general use of your notebook battery.


    All batteries in any device are a consumable meant to be replaced eventually after much time, even under perfect use conditions.

     

    If the massive amount of data that exists on lithium batteries were to be condensed into a simplex, helpful, and memorable bit of information it would be:

     

    1. While realistically a bit impractical during normal everyday use, a lithium battery's longevity and its chemistry's health is most happy swinging back and forth between 20% and 85% charge roughly.

     

    2. Do not purposefully drain your battery very low (10% and less), and do not keep them charged often or always high (100%).

     

    3. Lithium batteries do not like the following:

    A: Deep discharges, as meaning roughly 10% or less. Avoid this in all instances if you can. This is hard on your battery.

    B: Rapid discharges as referring to energy intensive gaming on battery on a frequent basis (in which case while gaming, if possible, do same on power rather than battery).

    C: Constant inflation, as meaning always or most often on charge, and certainly not both in sleep mode and on charge always or often.

     

    From Apple on batteries:

    http://www.apple.com/batteries/notebooks.html

    http://support.apple.com/kb/HT1446

    "Apple does not recommend leaving your portable plugged in all the time."

     

     

     

     

     

     

    Proper understanding of a battery charge cycle

    battery.jpg

    A charge cycle means using all of the battery’s power, whether that is at once, or over several shorter battery discharges and recharges.

     

    Two examples for clarification:

    As a first example, where one fully charged battery is discharged down to 10%, then fully recharged, then using 10% of that full charge, this counts as 1 cycle since the total of both discharges is 100% of a full charge of use.

     

    In the second example, where one fully charged battery is discharged down to 40%, then fully recharged, then using 40% of that full charge, this also counts as 1 cycle since the total of both discharges is 100% of a full charge of use.

     

    While both examples are that of a single charge cycle, the first example is more aggressive against the lithium battery chemistry than is the second example. In short, collective overall gentle shallow or mid-range draining of your lithium battery is a better use condition than is the first example of deep-draining of the battery.  While both are quantitatively identical as a single charging cycle, they are wholly different qualitatively on the battery chemistry, which is directly related to its ultimate longevity and health.

     

    In short, it is the near and mid-term life of the battery as relates to its proper care (or lack thereof) that is to be looked after.

     

    Priorities in order of decreasing importance for battery care are:

    1. Avoiding deep discharges of the battery.

    2. Avoiding having your battery constantly on charge or on charge and in sleep mode.

    3. When playing graphics intense games, use your notebook plugged in when possible.

    4. Reduction of battery cycles by plugging into power when on the go, or when accessible.

     

    A person who has, for example, 300 charge cycles on their battery and is recharging at say 40% remaining of a 100% charge has a better battery condition state than, say, another person who has 300 charge cycles on their battery and is recharging at say 10-15% remaining on a 100% charge. DoD (depth of discharge) is vitally important on the wear and tear on your Macbook’s battery, much more so than is the counting of charge cycles. There is no set “mile” or wear from a charge cycle in specific. Frequent high depth of discharge rates (draining the battery very low) on a Lithium battery will greatly hasten the lowering of maximum battery capacity.

     

    Understand that a charge cycle is a general parameter of use, but is not directly related to the short-term or mid-term abuse of the battery, which can rapidly hasten a shorter lifespan, regardless of what the actual cycle count on the battery indicates.


    Proper considerations for near-term care of the battery is of utmost importance. Abuse of the battery is entirely avoidable, long-term eventual old age deterioration of the battery is entirely unavoidable.


    Apple’s adaptive charging system mitigates much potential for accidental battery misuse or abuse; however it is still readily possible to abuse the battery and thereby affect battery health.

  • by Ale47099,

    Ale47099 Ale47099 Jun 7, 2014 11:59 PM in response to PlotinusVeritas
    Level 1 (0 points)
    Jun 7, 2014 11:59 PM in response to PlotinusVeritas

    Sweet, thanks for all the tips, really appreciate it!

  • by PlotinusVeritas,

    PlotinusVeritas PlotinusVeritas Jun 8, 2014 12:09 AM in response to Ale47099
    Level 6 (14,806 points)
    Jun 8, 2014 12:09 AM in response to Ale47099

     

    Ale47099 wrote:

     

    Sweet, thanks for all the tips, really appreciate it!

     

     

    Sweet

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