Think Lithium! - Hewlett Packard

This is a discussion on Think Lithium! - Hewlett Packard ; Are you doing heavy math every day and worry about empty battery? I changed my good old 4Mhz HP48SX with 1.1MB Ram to Lithium-battery. They are chinese second source from old Nokia 9300. http://www.criseis.ruhr.de/batt1.jpg http://www.criseis.ruhr.de/batt2.jpg Fit very well and in ...

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Thread: Think Lithium!

  1. Think Lithium!


    Are you doing heavy math every day and worry about empty battery?

    I changed my good old 4Mhz HP48SX with 1.1MB Ram to
    Lithium-battery.
    They are chinese second source from old Nokia 9300.

    http://www.criseis.ruhr.de/batt1.jpg
    http://www.criseis.ruhr.de/batt2.jpg

    Fit very well and in 1-2 years I can say how long I can use between
    charging.

    Olaf

    p.s: Of course you need a selfmade lithium battery charger, but that
    is to complicate for this newsgroup. .-)

  2. Re: Think Lithium!

    On Mar 17, 12:22 pm, Olaf Kaluza wrote:
    > p.s: Of course you need a selfmade lithium battery charger, but that
    > is to complicate for this newsgroup. .-)


    If you use the MAX 1555, like I did in my lithium powered 49g+
    http://jeisch.googlepages.com/hp-49gplus the charger is pretty
    simple. I used the usb input, but it can also take any DC source
    between 3.7 and 7 volts.

    I like that you fit the whole thing in the battery compartment. Good
    job.

    -Jonathan

  3. Re: Think Lithium!

    bokubob wrote:


    >If you use the MAX 1555, like I did in my lithium powered 49g+
    >http://jeisch.googlepages.com/hp-49gplus the charger is pretty
    >simple. I used the usb input, but it can also take any DC source
    >between 3.7 and 7 volts.


    I charge my battery with a selfmade charger I build with a
    microcontroller that can charge/discharge, measure Ri, Capacity and so
    on.

    If I like to build something inside of calculator I can recomend BQ24108
    from Texas. It did not waste so much space and you can use 6-16V. That
    is good for charging in cars.

    I used it for my PDA powersupply:

    http://www.criseis.ruhr.de/powerbox/powerbox.html

    Perhaps you can steal the idea or a part of the layout, because it is
    complicate.

    Olaf

  4. Re: Think Lithium!

    Olaf Kaluza wrote:

    > Fit very well and in 1-2 years I can say how long I can use between
    > charging.


    Why use rechargeable lithium-batteries?

    When the alkalines, i have actually in my 49g+ are empty, i will replace
    them by non-rechargeable lithium batteries.

    I think that should be enough energy for the next 3 - 4 years

    The problem of lithium-accumulators is, that they have a very short
    lifetime. Only 3 years, sometimes a bit longer but with a significant loss
    of capacity.

    Volker
    --
    Im übrigen bin ich der meinung, dass TCPA/TCG verhindert werden muss

  5. Re: Think Lithium!

    Volker Neurath wrote:


    >Why use rechargeable lithium-batteries?


    Because battery become empty only at weekend!

    >The problem of lithium-accumulators is, that they have a very short
    >lifetime. Only 3 years, sometimes a bit longer but with a significant loss
    >of capacity.


    No, thats wrong. For example the battery of my Zaurus SL-C750 is now
    5-6years old and I can use it for 5-6h without any problem. (2h with
    WLAN on)
    And I have many (5-6) torches with lithium battery. I made them myself
    with old battery from laptop and they are working very well.

    Oh..and I bought 20 of lithiumbattery that I used for my 48SX at ebay
    for only 11.50Euro...

    Olaf


  6. Re: Think Lithium!

    On Mar 20, 12:20 pm, Volker Neurath wrote:
    > Why use rechargeable lithium-batteries?
    >
    > When the alkalines, i have actually in my 49g+ are empty, i will replace
    > them by non-rechargeable lithium batteries.
    >
    > I think that should be enough energy for the next 3 - 4 years


    You mean like Energizer 1.5V lithium AAAs? Like these:
    http://data.energizer.com/PDFs/l92.pdf

    As you can see, the capacity of lithium batteries at low power draw is
    the same as alkaline. Only at high discharge rates (>200mA) does the
    internal resistance matter enough to reduce the effective capacity.

    If you go back to Eric's thread on current draw for the hp 50g:
    http://groups.google.com/group/comp....r+consumption#
    you'll see that the maximum draw in a 50g is 92.0mA.

    So, if you look at the capacity at 100mA on the energizer spec sheet,
    you'll see that your lithium would have an effective capacity of
    1200mAh, where an alkaline has a little over 900mAh.

    So, you might be getting something "better" than the energizers, but
    since lithium and alkalines are basically identical at low current, I
    don't see where your excitement comes from.

    You'll spend about the same amount on your non-rechargeable as I paid
    for mine, but mine is... you know, rechargeable.

    -Jonathan

    > The problem of lithium-accumulators is, that they have a very short
    > lifetime. Only 3 years, sometimes a bit longer but with a significant loss
    > of capacity.


    It's not a time issue, is a charge, recharge issue. Probably figure
    at least 100 recharge cycles before the capacity drops noticably. I
    dare say, in a calculator, that will be a bit more than 3 years.

    Please feel free to inform me of facts that I'm not aware of.

    Cheers,
    -Jonathan

  7. Re: Think Lithium!

    bokubob wrote:


    >Please feel free to inform me of facts that I'm not aware of.


    When a lithium-battery becomes old you will find at first that the
    inner resistance goes up. This is a big problem for high power devices
    like a laptop. But if your device needs very low power than you can
    use the battery very long.

    For example, I wrote I build some torches myself. One of them I made
    7-8 years ago. I used two 18650cells from a _bad_ old laptop battery at
    this time. Four years ago I used this torch in my garage for
    repairing my car. After that I forgot the torch there and found it one
    year ago. So it stays there three hot summer and three cold winter.
    I switched it on and it worked without a problem, it was even well
    charged. I tested it because I was interested about it.

    For this reason I expect a very long live of lithium battery inside my
    HP48SX.

    Olaf

  8. Re: Think Lithium!

    bokubob wrote:

    >> I think that should be enough energy for the next 3 - 4 years

    >
    > You mean like Energizer 1.5V lithium AAAs? Like these:
    > http://data.energizer.com/PDFs/l92.pdf


    Indeed.

    > As you can see, the capacity of lithium batteries at low power draw is
    > the same as alkaline. Only at high discharge rates (>200mA) does the
    > internal resistance matter enough to reduce the effective capacity.
    >
    > If you go back to Eric's thread on current draw for the hp 50g:
    >

    http://groups.google.com/group/comp....r+consumption#
    > you'll see that the maximum draw in a 50g is 92.0mA.
    >
    > So, if you look at the capacity at 100mA on the energizer spec sheet,
    > you'll see that your lithium would have an effective capacity of
    > 1200mAh, where an alkaline has a little over 900mAh.
    >
    > So, you might be getting something "better" than the energizers, but
    > since lithium and alkalines are basically identical at low current,


    Ok, that ist the reason why i felt that in the lithiums in my tv's remote
    control didn't do much longer than the alkalines.

    > I don't see where your excitement comes from.


    Besides the 49g+ i call an HP IR printer my own. And in the printer, the
    lithiums outclass the alkalines - i testet that several times.

    >> The problem of lithium-accumulators is, that they have a very short
    >> lifetime. Only 3 years, sometimes a bit longer but with a significant
    >> loss of capacity.

    >
    > It's not a time issue, is a charge, recharge issue.


    This is true for non-lithium accumulators but not for lithiums.

    Lithium accumulators suffer from a significiant loss of capacity after about
    three to five years, regardles wether used or not and regardles if stored
    fully recharged, partly recharged or empty.
    --
    Im übrigen bin ich der meinung, dass TCPA/TCG verhindert werden muss

  9. Re: Think Lithium!

    On Mar 21, 11:58 am, Olaf Kaluza wrote:
    > For example, I wrote I build some torches myself. One of them I made
    > 7-8 years ago. I used two 18650cells from a _bad_ old laptop battery at
    > this time. Four years ago I used this torch in my garage for
    > repairing my car.


    Every once in a while, the differences in meanings between American
    English and British English can be somewhat humorous (er, uh,
    humourous). In light of regular reports of the behavior (behaviour)
    of laptop batteries, I found this to be such a case.

    "Sony Laptop Battery Torches Desk"
    http://blog.wired.com/gadgets/2007/0...aptop_bat.html

    Let's hope your garage and car faired better with your "torch" than
    the desk did.

    -wes

  10. Re: Think Lithium!

    In article
    <2cc21152-aabc-40ef-9de3-96cdb5b39e0e@c65g2000hsa.googlegroups.com>,
    Wes wrote:

    > On Mar 21, 11:58 am, Olaf Kaluza wrote:
    > > For example, I wrote I build some torches myself. One of them I made
    > > 7-8 years ago. I used two 18650cells from a _bad_ old laptop battery at
    > > this time. Four years ago I used this torch in my garage for
    > > repairing my car.

    >
    > Every once in a while, the differences in meanings between American
    > English and British English can be somewhat humorous (er, uh,
    > humourous). In light of regular reports of the behavior (behaviour)
    > of laptop batteries, I found this to be such a case.
    >
    > "Sony Laptop Battery Torches Desk"
    > http://blog.wired.com/gadgets/2007/0...aptop_bat.html
    >
    > Let's hope your garage and car faired better with your "torch" than
    > the desk did.
    >
    > -wes


    Was it G.B.Shaw who remarked that Great Britain and the United States
    were two countries separated by a common language?

  11. Re: Think Lithium!

    Wes wrote:

    > Every once in a while, the differences in meanings between American
    > English and British English can be somewhat humorous (er, uh,
    > humourous).


    I fear the humour is not so easy to see if your mother language
    is German. .-)


    > "Sony Laptop Battery Torches Desk"
    > http://blog.wired.com/gadgets/2007/0...aptop_bat.html


    > Let's hope your garage and car faired better with your "torch" than
    > the desk did.


    Hhm I will read your link later, because this email is writen in my
    garage with my beautiful Zaurus and his nice LCD that needs no torch.
    :-D


    Olaf

  12. Re: Think Lithium!

    olaf@criseis.ruhr.de wrote:

    > Wes wrote:
    >
    >> Every once in a while, the differences in meanings between American
    >> English and British English can be somewhat humorous (er, uh,
    >> humourous).

    >
    > I fear the humour is not so easy to see if your mother language
    > is German. .-)


    Huh? that't easy, try www.leo.org

    But i'll try to explane it:

    "torch" is one word for the german "Taschenlampe" - but only in british
    english.
    In american english "torch" ist a person who lights something in order to
    destroy it, and "to torch" means just that: to light s.th. to destroy.

    Teh correct word fpr "Taschenlampe" in american english is "flashlight"

    Volker
    who is, like you, NOT an english person
    --
    Im übrigen bin ich der meinung, dass TCPA/TCG verhindert werden muss

  13. Re: Think Lithium!

    > > I fear the humour is not so easy to see if your mother language
    > > is German. .-)


    Sorry, I should have explained.

    > But i'll try to explane it:
    >
    > "torch" is one word for the german "Taschenlampe" - but only in british
    > english.
    > In american english "torch" ist a person who lights something in order to
    > destroy it, and "to torch" means just that: to light s.th. to destroy.
    >
    > Teh correct word fpr "Taschenlampe" in american english is "flashlight"
    >
    > Volker
    > who is, like you, NOT an english person


    This is correct, but for americans, the most common use of "torch" as
    a noun always refers to something that has an open flame, such as the
    Olympic Torch, or what you would see being carried through the jungle,
    or a gas torch used in welding.

    Your usage was perfectly correct, it's just that with all the news
    reports, the thought of _trying_ to create a flaming torch from your
    laptop battery struck me as being funny.

    -Wes Loewer (or Löwer as my Großpapa spelled it, uh, spelt it)

  14. Re: Think Lithium!

    Wes wrote:

    > This is correct, but for americans, the most common use of "torch" as
    > a noun always refers to something that has an open flame, such as the
    > Olympic Torch, or what you would see being carried through the jungle,
    > or a gas torch used in welding.


    I know, but i just forgot to mention this.

    > Your usage was perfectly correct, it's just that with all the news
    > reports, the thought of _trying_ to create a flaming torch from your
    > laptop battery struck me as being funny.




    That's why i referred to "flashlight" instead of "torch".

    >Wes Loewer (or Löwer as my Großpapa spelled it, uh, spelt it)


    German too?

    Volker
    --
    Stop TCPA/TCG now!

  15. Re: Think Lithium!

    On Mar 23, 1:49 pm, Volker Neurath wrote:

    > >Wes Loewer (or Löwer as my Großpapa spelled it, uh, spelt it)

    >
    > German too?


    In heritage, yes, but the only German I heard growing up was when my
    parents used it as the "secret parent language."

    -wes

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