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Laptop battery life

  1. Nov 9, 2011 #1
    I have been trying to maximize the life time of my laptop battery. My approach to that is to almost use up the charge in the battery then immediately charge it. It is always annoying when the battery have 5% left, because that's when it hibernates automatically. Can I change the settings so it won't do so? Also, what are the differences between "Total Charge" and "Primary Charge" of a laptop battery; there are usually more "Total Charge" than "Primary Charge".

    Do you think this method is effective? What else can I do?
  2. jcsd
  3. Nov 9, 2011 #2


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    Staff: Mentor

    Unless your laptop is at least 15 years old, that is almost certainly not the way to go about prolonging battery life. :mad:

    You do need to indicate the chemistry of your battery. If it's a typical Li-Ion cell, then (from memory) its life is maximized by keeping it cool and its state of charge at around 50%, never charging to fully charged, and certainly never discharging to a really low state. (Though I think they all have protection circuits to prevent total discharge, because it is so damaging. As is over-charging.)

    You should endeavour to use the laptop off mains power as much as possible. Otherwise, there is generally not a lot you can do, without severely hampering the convenience or your use of the computer. If you get 3 years out of a battery, consider yourself to have done well; that seems to be "typical".
  4. Nov 9, 2011 #3


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    Staff: Mentor

    Last edited by a moderator: May 5, 2017
  5. Nov 10, 2011 #4
    My computer came with an option to have the battery only charge to 80% when plugged in.

    Also, don't let it get below 30%, and try not to cycle it a lot.
  6. Nov 10, 2011 #5
    Full Charge, use it till it discharges to the low battery warning and pulgin to power .

    This helps the battery life long , ensure you do a full charge after the low battery warning , it is not advisable to plug-in for few minutes and see that some charge is there in laptop and start using it - It is a wrong method.
  7. Nov 10, 2011 #6
    that's true for Ni-Cd batteries. He's asking about laptop batteries which are Li-Ion since 1999.
  8. Nov 11, 2011 #7


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    Staff: Mentor

    Always striving for clarity in English expression, I failed to notice the ambiguity I introduced in my own sentence, above.

    I meant you should endeavour to power the laptop using mains power whenever possible, to avoid unnecessary use of the internal battery.

    In contemporary usage, "off mains" has also come to mean "not using the mains"
  9. Nov 15, 2011 #8
    You are doing the most to harm your battery. This laptop is used every day now for over eight years. It still has the original battery. This battery is still good for at least two hours.

    Laptop batteries were never intended for operation without AC mains. Battery function is similar to that of a UPS. To provide temporary power when AC mains is are not available. A lithium battery is only rated for 300 complete discharges. Latest batteries may now be good for 500 or 600 power cycles (HP was testing these new version in selected laptops - unknown to the customers). Life expectancy increases 'exponentially' when a battery discharges less.

    Learn from engineering sources. For example, hybrids in America must not have battery failure for 100,000 miles. Due to this higher reliability requirement, American hybrids let their lithium batteries discharge less than in same models for other countries. Same batteries last significantly longer due to less discharging. Same principle applies to your laptop.

    The worst you can do to a laptop battery is to use that battery as if a primary power source. Worst is what you are doing. Most have been told by hearsay something completely different. Some are even confusing your lithium battery with an old problem found in one type of NiCd battery. As if all rechargeable batteries operate same.

    But again, I have never replaced any battery in any laptop in over five years. This battery is now over eight years old.
  10. Nov 15, 2011 #9
    Okay! Should I summarize? So, I should minimize the use of the laptop battery which according to the PC has a battery chemistry of "LION" (stands for Lithium ion?).

    But what if I have to use it? Do I charge it at 30% or almost 0%? How much do I charge it to? 70% or 100%?
  11. Nov 15, 2011 #10
    A relationship between discharge and life expectancy was described previously - exponential. I rarely use a battery down to less than 80%. Therefore its 300 discharge cycles are hardly used.

    If you must use the battery, then do not worry about battery life expectancy. You are using the battery with expectation of hitting that 300 or 500 discharge cycles quickly. Maybe within a year or two. Shorter discharge cycles exponentially increases battery life expectancy. Previously described was a worst thing one can do to increase battery life expectancy.
  12. Nov 20, 2011 #11
    So do I charge it at 30% or almost 0% and do I charge it to 70% or 100%?
  13. Nov 26, 2011 #12
    Charge it whenever possible, going below 30% is much worse than keeping it above 70%. If you are not planning on using it in the very-near future (the next few days) charge it to 40-60% and store it in a cool (not cold) place. If you are planning on using it soon best to charge it fully to 100% in order to avoid running it low.

    Try to avoid going below 30% charge if you can. Obviously there will be times where you will need to use part or all of that last 30%; don't feel bad about it, but avoid it if possible by planning ahead.

    As others have noted, the above applies to lithium-ion batteries used in most modern rechargeable electronics.
  14. Dec 26, 2011 #13
    I use Sony vaio laptop and its battery life is 2 and half hours almost..But I wish that it could have more battery life,I hate when they show low battery...This is the only thing I hate,normally all laptop has that much life only..
  15. Jan 9, 2012 #14
    Here are some tips to increase the battery life of your laptop: Always try and run all those software’s or application that you need to run and close down all the background applications running on your laptop, don’t run games and heavy software’s on your laptop until its designed to do so, keep your screen brightness at optimum level, use earphones or headphones instead of external speakers of laptop and use power saver mode.
    IT Support West Midlands
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