Recalibrating battery chip - Portable

This is a discussion on Recalibrating battery chip - Portable ; Hello, I'm wondering if there are any tools for Linux which will allow me to "recalibrate" the chip in my laptop battery (an IBM Thinkpad 770). Most of the discussions I've seen here were about measuring the state of the ...

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  1. Recalibrating battery chip

    Hello,

    I'm wondering if there are any tools for Linux which will allow me
    to "recalibrate" the chip in my laptop battery (an IBM Thinkpad 770).
    Most of the discussions I've seen here were about measuring the state
    of the battery and taking appropriate activity, but not about doing
    anything with the chip in the battery itself. My battery shows
    symptoms which lead me to suspect that the cells might still be ok,
    but that the chip will not allow them to be charged, anyway (see below
    for the full story, if you really want to know :-)

    Some time ago someone here described how he had hooked up his battery
    externally to a PC to talk to the chip, but he thought that it could
    not be accessed while the battery is inserted in the laptop itself. On
    the other hand I've heard people claim that there are DOS utilities
    which can talk to the chip and reset it (but I've never actually seen
    or tested such a utility). If this is true, then it should be possible
    to access the chip under Linux as well. Any suggestions?

    Thanks and a nice weekend to all,

    Hans-Peter

    ************************************************** ********************

    Here is the full story:

    The battery has been doing fine (at 100% capacity, as far as I can
    tell) up until a few weeks ago. In fact, to prolong its good health,
    I took it out of the laptop, using another, nearly dead one when the
    laptop is hooked to AC power, which is most of the time.

    Recently I wanted to charge the battery to use it on a trip. The
    display showed that the laptop stopped charging it at 36%, which had
    never happened before. I tried the usual, i.e. running it down as low
    as it would go, and recharge it. This time the charging process
    stopped around 12%. I then took the battery and hooked it to an
    external charger. Adjusting the current to about 500mA, the battery
    seemed to accept the charge. After a day or so, the display showed
    100% when I inserted the battery into the laptop. It ran for about an
    hour (about a third of what I got before), then the display suddenly
    dropped to about 5%. This time, when I reconnected the AC power, the
    battery did not get charged at all. After connecting the battery to
    the external charger again, I found that the current going into the
    battery was only about 0.5mA. I then tried to run the battery down to
    0%, but the that didn't change anything. Evidently, the chip in the
    battery has somehow decided that it does not want any charge going
    into the cells. Why, I have no idea.

    So, the battery is not dead (it can still power the laptop, even
    though it is showing 0%, with the machine immediately tring to shut
    down), but it does not want to be charged. Any idea how I could
    persuade it to cooperate?



  2. Re: Recalibrating battery chip

    On Sun, 13 Jul 2003, Hans-Peter Nollert
    wrote:
    > Hello,
    >
    > I'm wondering if there are any tools for Linux which will allow me
    > to "recalibrate" the chip in my laptop battery (an IBM Thinkpad 770).
    > Most of the discussions I've seen here were about measuring the state
    > of the battery and taking appropriate activity, but not about doing
    > anything with the chip in the battery itself. My battery shows
    > symptoms which lead me to suspect that the cells might still be ok,
    > but that the chip will not allow them to be charged, anyway (see below
    > for the full story, if you really want to know :-)


    What kind of battery is it? Lithium Ion batteries do not need to be fully
    discharged between charging cycles, and should never be discharged below
    10% (so I heard). A chip that keeps track of charge cycles and should
    prevent overcharging. I do not know if it can be reset internally, or
    if that would do any good. I have a very old TI P133 laptop from work and
    its original Li-I batteries are still fully functional after many years.
    I purchased my Sony laptop January 2000 and its battery is still good
    (admittedly mostly used on AC power as wireless terminal for my headless
    PCs).

    NiCads and nickel metal hydride batteries DO need to be dischaged between
    charging cycles or they will remember that and no longer hold a full
    charge. But that is not the case with Li-Ion batteries.

    So it is possible that you are your own worst enemy and ruined your
    battery by not following instructions in your owner's manual, charging it
    outside of the computer (if BIOS is involved in preventing overcharge), or
    treating it like a different type of battery than it actually is.

    --
    David Efflandt - All spam ignored http://www.de-srv.com/
    http://www.autox.chicago.il.us/ http://www.berniesfloral.net/
    http://cgi-help.virtualave.net/ http://hammer.prohosting.com/~cgi-wiz/

  3. Re: Recalibrating battery chip

    in article 3F10A0CC.D22F915C@tat.physik.uni-tuebingen.de, Hans-Peter Nollert
    at nollert@tat.physik.uni-tuebingen.de wrote on 7/12/03 6:59 PM:

    > Hello,
    >
    > I'm wondering if there are any tools for Linux which will allow me
    > to "recalibrate" the chip in my laptop battery (an IBM Thinkpad 770).
    > Most of the discussions I've seen here were about measuring the state
    > of the battery and taking appropriate activity, but not about doing
    > anything with the chip in the battery itself. My battery shows
    > symptoms which lead me to suspect that the cells might still be ok,
    > but that the chip will not allow them to be charged, anyway (see below
    > for the full story, if you really want to know :-)
    >
    > Some time ago someone here described how he had hooked up his battery
    > externally to a PC to talk to the chip, but he thought that it could
    > not be accessed while the battery is inserted in the laptop itself. On
    > the other hand I've heard people claim that there are DOS utilities
    > which can talk to the chip and reset it (but I've never actually seen
    > or tested such a utility). If this is true, then it should be possible
    > to access the chip under Linux as well. Any suggestions?
    >
    > Thanks and a nice weekend to all,
    >
    > Hans-Peter


    The "chip" in a smart battery provides information on the status of the
    battery. Control over charging/discharging is handled within the laptop
    itself. Any information that needs to be reset will be contained in the
    laptop and not the battery. The laptop "listens" to the battery is a truer
    statement than the laptop "talks" to the battery.

    An external charger has the feedback circuitry contained within the charger.
    There are advantages of having the feedback circuitry in the battery on a
    laptop. Most laptop batteries now report a serial number which enables the
    laptop to know which battery is installed. This allows the laptop to provide
    better estimates of time remaining on battery, time remaining until charged
    etc. based on the history of that battery. Since no feed back circuitry is
    provided within the laptop, failure of the "chip" in the battery will render
    the battery as useless as a failure of the battery cells.

    The apm driver allows one to read and change the information provided by the
    laptop power management system. Personally I would be unable to use that to
    any good advantage. While software will help in maximizing power usage,
    power availability and usage is a hardware function perhaps amenable to user
    tweaking, but never fully under user control.

    I did not see any information on the age of your battery or the type of
    battery. A search will turn up sites that provides tricks and tips for
    working with specific battery types. While there are tips and tricks that
    will help prolong battery life both in daily usage and overall life span,
    there is still a limit to what can be done and what can be expected.
    Batteries are consumable products and depending on how heavily you rely on
    your battery you may need to just replace it.

    bill
    --
    \/\/i||i@m ()\/e



  4. Re: Recalibrating battery chip

    William Ove wrote:

    > The "chip" in a smart battery provides information on the status of the
    > battery. Control over charging/discharging is handled within the laptop
    > itself. Any information that needs to be reset will be contained in the
    > laptop and not the battery.


    I don't think that's the complete story. When I hooked the battery
    to an external AC adapter (not a specialized battery charger, just
    an adapter that puts out X volts at Y amps), I could originally
    still charge the battery, if I kept the current to something like
    500mA. This seems low; given usual charging times for these
    batteries, it should easily take about 1A of charging current. If I
    tried to increase the current, it suddenly dropped to something like
    0.5mA. However, eventually the battery cut off the charging current
    altogether. Right now, it shows a funny behaviour: If I keep the
    battery connected to the AC adapter, the current is somewhere around
    0.5mA. Every few seconds, the current increases to about 5mA, to
    drop back to 0.5mA after about a second. All this is controlled by
    circuitry in the battery itself, since the AC adapter does not do
    anything fancy.

    Therefore the laptop does not really control the charging process.
    It tries to charge the battery, and if it does not accept the
    charge, the laptop just stops trying to charge it.

    BTW, this is a LI-Ion battery, probably about 2-3 years old (I don't
    know exactly, since I got it used). It has been working perfectly at
    full capacity for some time, and then suddenly developped these
    problems when it had not been in use for some time. I would think
    that if the cells were to blame, then it would die somewhat more
    slowly; that's why I suspect the "chip" to act up in some way.

    I have read accounts of people talking about these same symptoms:
    The battery could not be charged any more, even thoug it was not
    dead. They managed to "reset" it by either completely discharging
    it, or by using some piece of software, or some other magic
    procedure. Afterwards, it could be charged normally again. However,
    I have not been able to locate any such utility for my laptop (an
    IBM Thinkpad 770, about 4 years old).

    I tried searching the net, but my search only turned up sites giving
    very general tips for treating a Li-Ion battery. When I tried making
    the search more specific, it would not turn up anything at all.

    Hans-Peter



  5. Re: Recalibrating battery chip

    Hi there,

    Hans-Peter Nollert writes:

    [...]

    >BTW, this is a LI-Ion battery, probably about 2-3 years old (I don't
    >know exactly, since I got it used). It has been working perfectly at
    >full capacity for some time, and then suddenly developped these
    >problems when it had not been in use for some time. I would think
    >that if the cells were to blame, then it would die somewhat more
    >slowly; that's why I suspect the "chip" to act up in some way.


    Well, AFAIK LI-Ion batteries have a battery life time of 3
    years, regardless of being used or not. This is wisdom
    published by computer magazine c't, for instance. They've
    tested 'availability of notebook spare parts' at some time and
    came to the conclusion, that many notebook makers don't supply
    any after 3 years for consumer notebooks. In that article they
    advise against buying a spare LI-Ion battery with the notebook,
    as that would be as dead as the original one, when the three
    year lifetime was over.

    So, if your battery is closer to 3 years than 2 years, that
    might just explain it.

    Does your BIOS have a battery learning setup, perchance? I know
    the BIOS in my notebook does (F6 - battery learning program)

    Best Regards
    Martin
    --
    Martin Boening, mboen@t-online.de

    Absurdity, n.: A statement or belief manifestly inconsistent with one's
    own opinion. (Ambrose Bierce, "The Devil's Dictionary")

  6. Re: Recalibrating battery chip

    'Twas Thu, 17 Jul 2003 14:04:45 +0200 when all comp.os.linux.portable
    stood in awe as mboen@t-online.de (Martin Boening) uttered:

    >Well, AFAIK LI-Ion batteries have a battery life time of 3
    >years, regardless of being used or not. This is wisdom
    >published by computer magazine c't, for instance. They've
    >tested 'availability of notebook spare parts' at some time and
    >came to the conclusion, that many notebook makers don't supply
    >any after 3 years for consumer notebooks. In that article they
    >advise against buying a spare LI-Ion battery with the notebook,
    >as that would be as dead as the original one, when the three
    >year lifetime was over.


    When I read this I was flabbergasted. It is so out of step with my
    experience that I had to do a test.

    My Toshiba Tecra 700CT was manufactured in 1996. I purchased it used in
    1999, by which time Toshiba no longer manufactured any computer which took
    the same battery pack. I subsequently purchased some used batteries in
    July 2000. There are no dates on the batteries, but I paid $5 apiece, so
    I am sure they were not new.

    I usually use this computer plugged in. I thought my batteries would all
    be in good shape because they hadn't been used for many cycles, then I
    read this claim that they would go bad after two or three years. So I
    tested them.

    I have five Li-Ion batteries, and they are 5 to 7 years old. Each one was
    able to run this computer for nearly three hours. These batteries are
    nearly as good as new.

    --
    RB |\ © Randall Bart
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    nr |\ Please reply without spam I LOVE YOU 1-917-715-0831
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    l |/ MS^7=6/28/107 http://yg.cotut.com mailto:s@cotut.com

  7. Re: Recalibrating battery chip

    Hi there,

    my home PC is down, so I'll respond from here:

    On Sat, 09 Aug 2003 04:42:26 +0000, Randall Bart wrote:

    > 'Twas Thu, 17 Jul 2003 14:04:45 +0200 when all comp.os.linux.portable
    > stood in awe as mboen@t-online.de (Martin Boening) uttered:
    >

    [...]
    >
    > When I read this I was flabbergasted. It is so out of step with my
    > experience that I had to do a test.
    >
    >


    Well, in the latest issue c't has retracted their statement: according to
    their newest article there is indeed no 3 year limit, provided the battery
    is "well-kept". According to that piece the worst place to keep a battery
    is in the notebook, if the notebook is usually run on A/C power because it
    will get hot in there and get a lot of minimal charges. Getting hot
    supposedly accelerates oxidation, which is detrimental to battery
    lifetime.

    A well-made LI-Ion battery can, according to that, get much older than 3
    years - though the authors still set the limit at 5 years. A low-quality
    manufacturing process, OTOH, can shorten the lifetime exceedingly, if I
    interpret the article correctly.

    However, they now call the "3 year lifetime" a rumor, as if they never
    made such a statement. I guess I'll have to write them a letter on that,
    because in c't 7/2003 they were still involved in spreading just that
    information. (Maybe different authors though).

    Have fun
    Martin
    --
    Martin Boening, MB3792-ARIN | Martin.Boening@mch.sbs.de

    It is impossible to travel faster than light, and certainly not
    desirable, as one's hat keeps blowing off. (Woody Allen)


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