1. This forum section is a read-only archive which contains old newsgroup posts. If you wish to post a query, please do so in one of our main forum sections (here). This way you will get a faster, better response from the members on Motherboard Point.

Laptop battery loses charge when off??

Discussion in 'Laptops' started by micky, Feb 24, 2013.

  1. micky

    micky Guest

    Why are my laptops discharging when hibernated?

    My friend has an ACER Aspire One ZG5 netbook and I liked ti so much I
    bought something similar, an ACER Aspire One D250 netbook.

    I used t he first one a year ago for almost 2 weeks, and had no
    trouble with the battery, but this month, the battery went from fully
    charged to 1/3 charged in about 15 days when it wasn't used. I had
    hibernated it, closed it, and unplugged the charger.

    Now I see that my new one, which went unused for about a week, was
    done to 40% remaining. That one too I had hibernated, closed, and

    The first is about 4 years old, was refurbished, and came with a
    3-cell battery. It took over an hour or more to recharge.

    The second was new I think, about 465 days old and came with a 6 cell
    battery. When I got it, from ebay, it was 2/3 charged and took about
    an hour to charge the last 1/3.

    P.S. Is there a problem leaving an Acer netbook plugged in to the
    house charger all the time, until this is resolved?

    micky, Feb 24, 2013
    1. Advertisements

  2. Well if they are hibernating rather than being turned off,
    surely battery depletion should be expected. As I understand
    things (and I'll admit my knowledge is often outdated), when
    you put a PC into hibernation mode, it still keeps certain
    systems running so that the machine can be awoken by pressing
    keyboard keys and other inputs which require active
    electronics to scan them.

    Furthermore, it has to keep something alive that would tell
    the rest of the machine where to load the data it stored
    before going into one of your week long sleeps. OK, perhaps
    nowadays the BIOS and interface is set up to do all this while
    the electronics are actually powered down. But I doubt it, and
    in any case what's wrong with just turning the thing off?

    Anyway, if that four year old laptop has had a lot of use,
    then it is quite normal for the battery to suffer a bit.
    Lithium-Ion batteries have built in circuitry to manage them
    (mainly to stop them catching fire), this inevitably drains
    the battery slowly over time and if the battery is on it's
    last legs, that and whatever drain the PC may add to it even
    when the machine should be off (or worse, in hibernation) may
    well give you the loss of charge you experience.

    As for keeping them on their chargers, unless the charging
    system is poorly designed, I'd figure that should be fine. The
    transformer will always chew a little bit of power though,
    converting it mostly into heat. Depending on the design, this
    heat might be a problem (either in the transformer or the
    laptop), but I'll leave you to figure how much damage it can
    Computer Nerd Kev, Feb 24, 2013
    1. Advertisements

  3. micky

    Bob_Villa Guest

    As I understand "hibernation"...ram is loaded into the hard drive and uses the least amount of power. If you unplug a desktop that is hibernating, and plug it back-in days later...it won't "know" its been unplugged!
    I've had my Acer netbook (3yrs old with a 9-cell) for weeks without a problem, so it may be the battery as said.
    Bob_Villa, Feb 24, 2013
  4. I have a very nice Samsung Series 7 and it's behavior is exactly the
    same as you've noticed. I soon learned NOT to leave it in sleep mode
    for very long.
    Charlie Hoffpauir, Feb 24, 2013
  5. micky

    Bert Guest

    In Computer Nerd Kev
    No, that's what happens when you suspend. In hibernation, the contents
    of memory is written to disk and the machine is completely powered down.

    Batteries of all types are subject to self-discharge to some extent. The
    LiIon batteries usually used in laptops are supposed to do it at about
    10% per month. Older batteries might go faster.
    Bert, Feb 24, 2013
  6. micky

    micky Guest

    I'll admit that I brought up hibernation, but it doesn't work like you
    said. Normally, hibernation just copies the RAM to a file on t he
    harddrive -- in XP it is hiberfile.sys, which in my desktop is
    3,220,230,144 bytels long. ( I have 4 gigs of Ram but the file isn't
    that big either because XP can only use 3 Gig, or because when I
    hibernated I was using only the number of bytes of RAM listed)

    Now with the desktiop a few times, I've come back in the morning and
    found that it never finished shutting down, so it was using power all
    night, but that was obvious because the screen had some of the
    programs I'd been running still showing. If I had stuck around the
    night before, I could have made sure it closed down. With the
    laptops, I have made sure.
    In addition it sets one byte or bit to "hibernated" so that on normal
    start-up, if that byte is set, one of the first things it does is to
    copy pagefile.sys back to RAM.
    I think it's somewhere in the harddrive, probably a very early byte of
    pagefile.sys (or possibly the very presence of pagefile.sys)

    But it's like a note on the refrigerator door. It doesn't take any
    power to stay there. Compared to the schedule of tv shows to
    record that my non-calbe-company-supplied DVR forgets if there is a
    power failure,(while it does remember the tv shows it has recorded,
    because they are stored on a harddrive or DVD.)
    Hibernation brings you back to where you were when you turned the
    computer off. All the same programs are open and they're right where
    you left them. It's great. One has to actually shut down
    completely to make some updates take effect, like most security
    updates from MS, the ones with the yellow shield in the systray, and
    I believe some poorly written programs can require one to shut down
    completely (no hibernation) even earlier than that. When things stop
    working right, (after 3 or 4 or 7 days maybe), restarting the
    computer, not just hibernating and waking up, can usually make it work
    right again.

    Sleep, or Suspend, also brings you back to where you were, but with
    those two, the RAM has not been copied to t he HDD, so if there is a
    power failure not protected for by a Uninteruptable Power Supply, the
    computer forgets everything that was in RAM.

    I always save my data before Sleep and even before Hibernate. One
    time I intended to hibernate, but I pressed the wrong key and shut
    down instead. Had I not saved my date, it would have been gone.
    I'm not sure it does this all the time. I hibernated my own
    computer last night, and about 12 hours later, it was down to 95%. In
    6 days that would be 70%. I'll have to keep better track.
    So far, I only use the netbook when traveling, which I average about 2
    weeks a year. . If I were home, I' guess I'd let it run down,
    unless that is really a bad thing to do.
    Okay. ;-)

    micky, Feb 24, 2013
  7. micky

    micky Guest

    That's probably it. What about those batteries that sell for 12 or
    20 dollars, even for 6 cell. Do you only "get what you pay for", or
    do some places charge extra for the same thing.

    I once saw a Kodak refurbished digital camera in a "surplus" store for
    $50 , adn then found the same thing on line from $50 to $200! Even
    more than a new, not refurbished, Kodak camera of the same model and
    everything that cost 100! For cordless phones, I've seen the same
    vendor charging little more for 3 batteries than for one with the same
    mdel number.

    I'm not sure it's true anymore that you get what you pay for.
    micky, Feb 24, 2013
  8. micky

    micky Guest

    I bought this used and it came with a 6-cell. Supposed to be 6? oz.
    heavier, than 3 cell, I think. I didn't know there were 9-cell.
    Another 6? ounces?

    He said in the ebay ad that it was 2 years old, but I've found some
    dates in the computer from 2008. Yet this model, D250-1610, is only
    2 years old, and Belarc says the four system passwords were all only
    465 days old when I checked a couple days after I got the computer, so
    it seems like the computer must be only 465 days old. Maybe there's
    something he did to make the battery start to fail early??
    micky, Feb 24, 2013
  9. micky

    micky Guest

    When you say Start / Shut Down, the only options showing are Standby,
    Turn off, and Restart, but if you press Shift, Standby turns into
    Hibernate. However there is no need to press Shift. Just press H
    (for Hibernate) and it works even though that option is not showing.
    micky, Feb 24, 2013
  10. micky

    micky Guest

    I came across some info on this, straight from Acer, which is the
    brand of laptop I have.

    "Storing the battery:

    Do not charge up a battery, and then store it away. A stored battery
    should be used every three to four weeks. Let the battery fully
    discharge, then recharge to 40% if you plan to store it again. If you
    store a battery for longer than three to four weeks, the battery could
    fully discharge because the battery circuitry itself consumes power.

    "because the battery circuitry itself consumes power"!!!!!!!

    If you have a spare lithium-ion battery, use one exclusively and keep
    the other cool by placing it in the refrigerator. Make sure that it is
    wrapped protectively and that nothing will be dropped on it. Do not
    freeze the battery. Do not use old batteries. Avoid purchasing spare
    lithium-ion batteries and storing them for later use. Do not buy old
    stock, even if it is sold at clearance prices. While it makes sense to
    have 2 or 3 extra batteries, so that you always have a fresh one
    charged up and ready to go, if you buy batteries and store them for
    years, they may not work when you decide to use them.

    Consider removing the battery from your notebook when running on fixed
    power. However, remember that when you have removed the battery from
    your notebook while using it with an electrical outlet, the automatic
    battery charger no longer keeps the battery charged."

    My friend's, a 3-cell from the company that reconditioned his netbook
    4 years ago, perhaps Acer itself, keeps its charge quite well.

    Mine, a 6-cell on an Acer that is only about 2 years old, loses its
    charge much more quickly, 50% in a week or so. Maybe the previous
    owner kept the computer in a hot car

    Apparently that's better than leaving it unplugged.
    micky, Mar 13, 2013
  11. micky

    ~misfit~ Guest

    Yes, this has been the case for well over a decade now. The 'battery' is a
    collection of Li-Ion cells and some 'smart' circuitry which, amongst other
    things, monitors the state of each cell and attempts to level the load so
    that one cell aging prematurely doesn't take out the whole battery pack.

    Also the PU in the battery keep track of things like the serial number of
    the battery, the number of cycles it's undergone and the general health of
    the cells / battery. If there isn't enough power left to keep the PU powered
    up then your battery is bricked - even if the cells are in 90% good

    It's for this reason that, if you're going to re-pack a battery you need to
    apply a source of current to the PU and associated circuitry before you
    disconect the old cells. I've seen it done, a bench-top variable PSU and a
    couple leads with crocodile clips.... Clip them in just the right place with
    just the right voltage dialed in and then, and only then - you can remove
    the old cells and solder in new ones. Of course if the old battery's already
    bricked due to zero current then you're SOOL.

    It's not rocket science.

    "Humans will have advanced a long, long, way when religious belief has a
    cozy little classification in the DSM."
    David Melville (in r.a.s.f1)
    ~misfit~, Mar 14, 2013
  12. micky

    micky Guest

    I just checked my emails from 10 years ago, and no one wrote me about
    That sounds great, but it should do it for free. "I paid for this
    Sounds like too much regulation, government regulation..
    That selttles it. I'm not rebuilding any battery packs.
    I never said my limit was rocket science. It's far below that.

    micky, Mar 14, 2013
  13. micky

    ~misfit~ Guest

    Are you in the field of battery back design and management then?

    All electronic circuits need to use power from somewhere. There's no such
    thing as a free electron.
    Ok, are you.... Confused? It has nothing to do with governments. Without
    this smart battery management you'd be lucky to get 3 months from a battery
    pack. As it is I have 10 year old IBM X3x batteries that are only showing as
    haing a 20% wear level. That's phenomenal and completely impossible without
    the circuitry that monitors the cells, their temps when charging (and
    adjusts the charge current accordingly) and a bunch of other things.
    I might try it - if only because most of my machines don't have battery
    packs available off-the-shelf so anything I buy is going to be not only
    expensive but of iffy quality (and re-quire a non-bricked trade. If you do
    it yourself you can buy high-quality Japanese cells rather than commodity
    Chinese cells and end up with a battery pack that's can hold quite a bit
    more charge than the new one and wil last a good long time. can't be said
    for 80% of available re-builds.
    LOL, me too.
    You're welcome.

    "Humans will have advanced a long, long, way when religious belief has a
    cozy little classification in the DSM."
    David Melville (in r.a.s.f1)
    ~misfit~, Mar 15, 2013
  14. micky

    Top Guest

    micky formulated the question :
    Thank you for this little tip. I have a 4 yp laptop that has sat
    collecting dust because it would not charge. In fact it "seemed" as it
    would not "see" the charger. Could not get a power light to come on,
    even replaced the charger twice. I saw this today and thought what do I
    have to lose, it is seemingly dead as it sits. I took the battery off
    and stuck it in the freezer. For the heck of it I connected the charger
    to the laptop and guess what!?? I got a power light and the beast
    powered up. First time I've had it powered up in over 2 years. About 45
    minutes later I put the battery back in and it has accepted a full
    charge. I have to think the battery was low enough that the charge
    circuitry wouldn't let it charge. As long as the almost "dead" battery
    was in the laptop it wouldn't power up. Once the battery was not there
    it solved that part of the problem.

    Thanks for a hint that restored at dead laptop!

    Top the lurker
    Top, Mar 16, 2013
  15. micky

    micky Guest

    I'll have to remember this myself. Come to think of it, I have a
    laptop someone gave me becaue it was broken. Their daughter literally
    spilled Pepsi on the keyboard, and while that's not good, I would
    think it would have dried up by now (3 years later) **. And iirc, she
    was sort of chuby. If it was diet Pepsi, seems like there would be
    even less residue to cause problems. I'll take the battery out and
    try it witout it. I should have done that. And I'll put the battery
    in the freezer for an hour (my freezer is warmer than average) y i

    **Really, does even sugar-based Pepsi conduct electricity well enough
    to hurt a keyboard or whatever is under it? Especially at 12 or 19
    volts or whatever laptsps use?
    A pleasure to be of help. A day or two after I posted the previous
    post, I came acorss another article by Acer that said one should take
    one or two spare batteries with him so he'll always have a charged
    one. This and a couple other things were almost directly
    contradictory to what I posted (by Acer.) .
    micky, Mar 16, 2013
  16. I wonder whether the cooling is helping the Lithium-Ion cells or simply
    giving the control circuitry hell. I would suspect the second. In this
    case it's worth keeping in mind that charging up under voltage
    Lithium-Ion cells has the potential for causing a hot and perhaps
    firery death for the battery. With this in mind, I'd think twice
    before leaving the laptop to charge next to your curtains as normal
    or in some other situation where it tempts a firery fate.
    Last year I pulled apart a laptop I was given in order to 1) replace the
    fan that sounded like a lawn mower (literally) and 2) try to kill the
    terrible rotting coffee smell that was emitted every time the laptop
    warmed up. Inside, there was coffee residue everywhere but in the screen.
    In areas on the motherboard where it was especially caked on, it seemed to
    have corroded parts of the solder and formed lumps that I couldn't get
    off in some areas for fear of breaking off components before the coffee
    gave way. I was amazed the whole time that the thing was still working.

    I completely disassembled everything but the screen then cleaned the
    motherboard and other complex electronics by hand before washing
    all the plastic and simple electronic parts in the sink. After a few
    minutes on, the thing still stinks of coffee, but at least not quite
    as bad.

    The lesson I've learned is that this stuff might not short out after
    a spill, but something like Pepsi can likely still corrode component
    leads and solder. I also know how this can cause problems due to the
    added resistance to connections. My advice: get in there and look at
    the damage for yourself.

    As for the conductivity of Pepsi, if you have a multi-meter, simply
    pour a pool of Pepsi and use the resistance measurement function
    to tell you its conductivity. If the multimeter shows infinate
    resistance (a "1") on its highest scale while the probes are close,
    then the Pepsi won't conduct anything meaningful at laptop voltages.
    Computer Nerd Kev, Mar 16, 2013
  17. micky

    ~misfit~ Guest

    It's things like mp3 players and some older cellphones that usually have
    fiery Li-Ion "batteries" (actually not a battery at all, rather a single
    cell used in 'dumb' mode). Part of the function of most laptop battery's
    electronics is to monitor temps, usually in at least two places in the
    pack - and to shut off or reduce charging current if / when temps go outside
    of a pre-defined range.
    As long as it's stripped down of all 'add-on' components a laptop's
    motherboard can be [a]safely soaked for a few minutes, then washed in warm
    water with a little mild detergent. As long as it's then rinsed thouroughly
    a couple times in similarly warm water afterwards and completely dried
    afterwards it should be fine.

    [a] At your own risk of course. While I've safely done this myself I can't
    warrant that it will be fine for your machine - especially bearing in mind
    that there's likely to be an issue with it already or this wouldn't be

    I live in New Zealand and know quite a few IT people, some of whom have
    worked for periods in the south Pacific Islands for periods of time. The
    environment there can be *extremely* hostile to electronics with fine salt
    spray blowing right across a lot of the low-lying islands.

    I know of one guy in particular who worked in an island community in Samoa
    who would sell computers; both laptops and desktops, and offer a three-year
    warranty on them - but only if they were bought back for a week at the end
    of the first and second years. He would strip them down completely and he
    had slightly modified a dishwasher which he used to wash and dry the circuit
    boards of salty deposits each year. If customers were particularly close to
    the ocean he'd do it bi-annually.

    IIRC afterwards he would 'mist' the boards (as well as a bunch of the stuff
    that he deemed too delicate to go through the washer) to the point wher
    ethey were dripping with pure isopropanol. He would then let that evaporate
    in a drying cabinet he had made up that was connected by ducts to a
    dehumidifier. He told me that the environment was so hostile that, if such a
    regime wasn't undertaken computers wouldn't usually last more than 18 months
    tops (and that most companies wouldn't give / honour warranties on hardware
    used in the islands).

    "Humans will have advanced a long, long, way when religious belief has a
    cozy little classification in the DSM."
    David Melville (in r.a.s.f1)
    ~misfit~, Mar 17, 2013
  18. Yes, only another part of that circuitry is usually to forbid
    the charging of the cells if they are under the voltage where
    they begin to deteriorate. If this part of the circuitry is
    tricked into allowing the battery to be charged again, what's to
    say the other safety features aren't disabled as well?

    Yes I've heard of this being done, I've never been brave enough
    to do it myself though. My main fear is leaving moisture trapped
    in areas of the board, plus in that case some of the residue
    needed scraping with a screwdriver to remove, even after soaking
    with methylated spirits.
    Facinating, I wouldn't have thought it would be a problem that
    Computer Nerd Kev, Mar 17, 2013
  19. micky

    ~misfit~ Guest

    What I think happens is that, in one way or another, the circuitry is
    temporarilly changed briefly (until room temperature is reached) to allow a
    trickle charge through when it normally wouldn't. If the cell is actually
    OK, just has been let drain too far, then charging will continue and, in
    effect the battery will be bought back to life.

    If in fact the cell had been refused charge for some other reason - such as
    it had deteriorated due to having reached the end of it's useful life then
    it would get hot under charge, and wouldn't hold charge properly, and the
    now room-temperature monitoring circuits would pick that up and 'brick' it

    My point is that (I think) all you are doing is tricking the control circuit
    for as long as it takes the battery to warm up - not permanently. If any
    'marked-defective' cells that were really only drained too far have managed
    to take enough charge in that time for the PU to re-assess them as no longer
    being defective then I would think there is no danger. It's almost the same
    thing that would occur when replacing cells; The ciruitry reassesses them
    and then treats them accordingly.

    I'm told that a re-packed battery that uses the original protection and
    charging circuitry has to be cycled several times until the PU updates the
    state of the cells, stores and then starts to act on the new information. I
    think that this same proccess can be made to happen sometimes by chilling
    the battery pack and applying a charge to it while it's still cold. If cells
    were erronously marked as being dead due to sitting too long then there's a
    chance they can be given enough charge while the PU is basically asleep for
    it to then re-assess them - and sometimes that's all they needed.

    There is almost no chance of thermal runaway as, soon after leaving the
    freezer the protection circuits become operational again - in fact I think
    that it's likely always operational to some degree (heh!) - just that maybe
    the sub-zero temps delete or temporarilly obfuscate stored cell info from

    Anyway, in most laptops there is a second redundant protection circuit on
    the planar (I know that there is / was on IBM laptops - I think that most
    others would be the same.)

    That's why I rinse in quite warm water a couple times - so that when all
    trace of detergent has gone the PCB is still warm. Hopefully warm enough so
    that there's not enough moisture trappen anywhere to be trouble. After the
    few times I've done it I've either left it for a few days in the hot water
    cupboard or sat it in a very low oven with the door open. (Aim for about
    25ºC above room temp and dry air for ~30 mins if done in the oven.)
    Apparently, yes. It was a reliable source. Those humid and salty South
    Pacific Islands can be murder on (unprotected - or well ventillated as in
    cooling airflow) PCBs - especially ones that have very fine traces and tiny
    SM components.

    "Humans will have advanced a long, long, way when religious belief has a
    cozy little classification in the DSM."
    David Melville (in r.a.s.f1)
    ~misfit~, Mar 17, 2013
  20. Though it's still an unknown. Without analysing the circuit,
    you can't tell whether the battery has re-checked itself or
    the circuitry has a miss-designed failure mode where it allows
    the battery to be charged "dumb". Back to my original point,
    it seems enough of a risk to keep the machine away from the
    flammables while left on the charge the first few times.
    I don't know in general, but some IBM ThinkPads used Lithium-
    Ion batteries without control circuitry inside, hence they
    must have put this inside the Laptop.
    OK, I might give it a go next time I have a machine I don't
    care about too much.
    Computer Nerd Kev, Mar 18, 2013
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.