best protocol for carging a Laptop Battery - Hardware

This is a discussion on best protocol for carging a Laptop Battery - Hardware ; Bill in Co. wrote: > M.I.5¾ wrote: > >>"Bill in Co." wrote in message >>news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl... >> >>>M.I.5¾ wrote: >>> >>>>"ray" wrote in message >>>>news:6c1utvF3e9107U4@mid.individual.net... >>>> >>>>>On Fri, 20 Jun 2008 07:55:55 +0100, M.I.5Y wrote: >>>>> >>>>> >>>>>>"ray" wrote in message ...

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Thread: best protocol for carging a Laptop Battery

  1. Re: best protocol for carging a Laptop Battery



    Bill in Co. wrote:

    > M.I.5¾ wrote:
    >
    >>"Bill in Co." wrote in message
    >>news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>
    >>>M.I.5¾ wrote:
    >>>
    >>>>"ray" wrote in message
    >>>>news:6c1utvF3e9107U4@mid.individual.net...
    >>>>
    >>>>>On Fri, 20 Jun 2008 07:55:55 +0100, M.I.5Y wrote:
    >>>>>
    >>>>>
    >>>>>>"ray" wrote in message
    >>>>>>news:6bvaoaF3e31erU3@mid.individual.net...
    >>>>>>
    >>>>>>>On Thu, 19 Jun 2008 07:02:54 -0700, Rahul wrote:
    >>>>>>>
    >>>>>>>
    >>>>>>>>I just bought a new LiIon Laptop battery for my Dell Inspirion E1505
    >>>>>>>>(dual boot WinXP and Fedora).
    >>>>>>>>
    >>>>>>>>I gave it my initial 10 hour charge. Now what? I started using it
    >>>>>>>>but
    >>>>>>>>should I continue using it till the battery is drained and then
    >>>>>>>>recharge? Or should I only drain it partially? If it is not drained
    >>>>>>>>fully how will the Laptop learn (callibrate) itself to what the new
    >>>>>>>>capacity is?
    >>>>>>>>
    >>>>>>>>Or is it recommended that I only partially discharge it? What's best
    >>>>>>>>for the battery life?
    >>>>>>>>
    >>>>>>>>Another point: How many times should I cycle it this way? In the
    >>>>>>>>long
    >>>>>>>>term should I always wait for a full discharge; or can I charge it
    >>>>>>>>up
    >>>>>>>>from a partially-discharged state or does it not matter?
    >>>>>>>>
    >>>>>>>>I've gogled this but recieve conflicting advice.
    >>>>>>>
    >>>>>>>From what I've read Li-ion batteries are immune to the 'memory'
    >>>>>>>problems of NiCd batteries - it does not really matter much when you
    >>>>>>>charge them - do what is convenient for you. You should also be aware
    >>>>>>>that they loose about 10% capacity per year and there is not a damned
    >>>>>>>thing you can do about it.
    >>>>>>
    >>>>>>The evidence for this is largely anecdotal. I have batteries that are
    >>>>>>nearly 15 years old which, if this theory were true, would be useless.
    >>>>>
    >>>>>Really - I was not aware that rechargable Li-ion batteries had been
    >>>>>around
    >>>>>that long! So are they really as good as new or only carrying 15% of
    >>>>>original charge? Did you do any measurements?
    >>>>
    >>>>Li-ion batteries have ben around since the early part of the 1990's (and
    >>>>probably before). The examples cited all exhibit close to their
    >>>>original
    >>>>capacity (as far as I can tell - they run for near enough the orignal
    >>>>time).
    >>>>One of the batteries reports that it is only 70% charged after being
    >>>>fully charged, but otherwise works as well as the others.
    >>>
    >>>Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >>>the latter just cheaper (just guessing), and still used for economy, or
    >>>for some other reason?

    >>
    >>Nickel-Cadmium batteries are no longer recommended for new products. This
    >>is due to environmental concerns of the relatively toxic cadmium. They
    >>are
    >>available for support of older products that used them. Although Nickel
    >>Metal-Hydride appeared as a replacement, they are are not direct
    >>replacements in most applications.

    >
    >
    > Interesting - thanks.
    > But is this because they weren't available in the identical size packages,
    > with the same electrical capacity (i.e., voltage, ma-hrs, etc)? Or because
    > of the external charging circuitry (if any) possibly having different
    > requirements?
    >
    >

    See
    http://www.google.com/search?hl=en&q...=Google+Search
    and
    http://www.servocity.com/html/nicad_...batteries.html


  2. Re: best protocol for carging a Laptop Battery

    "M.I.5¾" writes:
    >
    >"Bill in Co." wrote in message
    >> Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >> the latter just cheaper (just guessing), and still used for economy, or
    >> for some other reason?

    >
    >Nickel-Cadmium batteries are no longer recommended for new products. This
    >is due to environmental concerns of the relatively toxic cadmium.


    More importantly, Nickel Metal-Hydride batteries have a much higher
    capacity than Nickel-Cadmium batteries (e.g., for AA Cells 2000mAh
    instead of 700mAh).

    > They are
    >available for support of older products that used them. Although Nickel
    >Metal-Hydride appeared as a replacement, they are are not direct
    >replacements in most applications.


    In most applications I know, they are direct replacements, because
    they produce the same voltage per cell (1.2V) and are available in the
    same form factors (AA, AAA).

    - anton
    --
    M. Anton Ertl Some things have to be seen to be believed
    anton@mips.complang.tuwien.ac.at Most things have to be believed to be seen
    http://www.complang.tuwien.ac.at/anton/home.html

  3. Re: best protocol for carging a Laptop Battery

    On Tue, 24 Jun 2008, Anton Ertl wrote:

    > "M.I.5¾" writes:
    >>
    >> "Bill in Co." wrote in message
    >>> Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >>> the latter just cheaper (just guessing), and still used for economy, or
    >>> for some other reason?

    >>
    >> Nickel-Cadmium batteries are no longer recommended for new products. This
    >> is due to environmental concerns of the relatively toxic cadmium.

    >
    > More importantly, Nickel Metal-Hydride batteries have a much higher
    > capacity than Nickel-Cadmium batteries (e.g., for AA Cells 2000mAh
    > instead of 700mAh).
    >
    >> They are
    >> available for support of older products that used them. Although Nickel
    >> Metal-Hydride appeared as a replacement, they are are not direct
    >> replacements in most applications.

    >
    > In most applications I know, they are direct replacements, because
    > they produce the same voltage per cell (1.2V) and are available in the
    > same form factors (AA, AAA).
    >
    > - anton


    _Optimal_ use of NiMH cells requires a bit different charger.

    -f

  4. Re: best protocol for carging a Laptop Battery

    OK, thanks for the links. There seems to be a set of advantages and
    disadvantages for each type.

    Bob I wrote:
    > Bill in Co. wrote:
    >
    >> M.I.5¾ wrote:
    >>
    >>> "Bill in Co." wrote in message
    >>> news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>>
    >>>> M.I.5¾ wrote:
    >>>>
    >>>>> "ray" wrote in message
    >>>>> news:6c1utvF3e9107U4@mid.individual.net...
    >>>>>
    >>>>>> On Fri, 20 Jun 2008 07:55:55 +0100, M.I.5Y wrote:
    >>>>>>
    >>>>>>
    >>>>>>> "ray" wrote in message
    >>>>>>> news:6bvaoaF3e31erU3@mid.individual.net...
    >>>>>>>
    >>>>>>>> On Thu, 19 Jun 2008 07:02:54 -0700, Rahul wrote:
    >>>>>>>>
    >>>>>>>>
    >>>>>>>>> I just bought a new LiIon Laptop battery for my Dell Inspirion
    >>>>>>>>> E1505
    >>>>>>>>> (dual boot WinXP and Fedora).
    >>>>>>>>>
    >>>>>>>>> I gave it my initial 10 hour charge. Now what? I started using it
    >>>>>>>>> but
    >>>>>>>>> should I continue using it till the battery is drained and then
    >>>>>>>>> recharge? Or should I only drain it partially? If it is not
    >>>>>>>>> drained
    >>>>>>>>> fully how will the Laptop learn (callibrate) itself to what the
    >>>>>>>>> new
    >>>>>>>>> capacity is?
    >>>>>>>>>
    >>>>>>>>> Or is it recommended that I only partially discharge it? What's
    >>>>>>>>> best
    >>>>>>>>> for the battery life?
    >>>>>>>>>
    >>>>>>>>> Another point: How many times should I cycle it this way? In the
    >>>>>>>>> long
    >>>>>>>>> term should I always wait for a full discharge; or can I charge it
    >>>>>>>>> up
    >>>>>>>>> from a partially-discharged state or does it not matter?
    >>>>>>>>>
    >>>>>>>>> I've gogled this but recieve conflicting advice.
    >>>>>>>>
    >>>>>>>> From what I've read Li-ion batteries are immune to the 'memory'
    >>>>>>>> problems of NiCd batteries - it does not really matter much when
    >>>>>>>> you
    >>>>>>>> charge them - do what is convenient for you. You should also be
    >>>>>>>> aware
    >>>>>>>> that they loose about 10% capacity per year and there is not a
    >>>>>>>> damned
    >>>>>>>> thing you can do about it.
    >>>>>>>
    >>>>>>> The evidence for this is largely anecdotal. I have batteries that
    >>>>>>> are
    >>>>>>> nearly 15 years old which, if this theory were true, would be
    >>>>>>> useless.
    >>>>>>
    >>>>>> Really - I was not aware that rechargable Li-ion batteries had been
    >>>>>> around
    >>>>>> that long! So are they really as good as new or only carrying 15% of
    >>>>>> original charge? Did you do any measurements?
    >>>>>
    >>>>> Li-ion batteries have ben around since the early part of the 1990's
    >>>>> (and
    >>>>> probably before). The examples cited all exhibit close to their
    >>>>> original
    >>>>> capacity (as far as I can tell - they run for near enough the orignal
    >>>>> time).
    >>>>> One of the batteries reports that it is only 70% charged after being
    >>>>> fully charged, but otherwise works as well as the others.
    >>>>
    >>>> Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >>>> the latter just cheaper (just guessing), and still used for economy, or
    >>>> for some other reason?
    >>>
    >>> Nickel-Cadmium batteries are no longer recommended for new products.
    >>> This
    >>> is due to environmental concerns of the relatively toxic cadmium. They
    >>> are
    >>> available for support of older products that used them. Although Nickel
    >>> Metal-Hydride appeared as a replacement, they are are not direct
    >>> replacements in most applications.

    >>
    >>
    >> Interesting - thanks.
    >> But is this because they weren't available in the identical size
    >> packages,
    >> with the same electrical capacity (i.e., voltage, ma-hrs, etc)? Or
    >> because
    >> of the external charging circuitry (if any) possibly having different
    >> requirements?
    >>
    >>

    > See
    > http://www.google.com/search?hl=en&q...=Google+Search
    > and
    > http://www.servocity.com/html/nicad_...batteries.html




  5. Re: best protocol for carging a Laptop Battery

    A-yep, as it is with most things in life! ;-)

    Bill in Co. wrote:

    > OK, thanks for the links. There seems to be a set of advantages and
    > disadvantages for each type.
    >
    > Bob I wrote:
    >
    >>Bill in Co. wrote:
    >>
    >>
    >>>M.I.5¾ wrote:
    >>>
    >>>
    >>>>"Bill in Co." wrote in message
    >>>>news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>>>
    >>>>
    >>>>>M.I.5¾ wrote:
    >>>>>
    >>>>>
    >>>>>>"ray" wrote in message
    >>>>>>news:6c1utvF3e9107U4@mid.individual.net...
    >>>>>>
    >>>>>>
    >>>>>>>On Fri, 20 Jun 2008 07:55:55 +0100, M.I.5Y wrote:
    >>>>>>>
    >>>>>>>
    >>>>>>>
    >>>>>>>>"ray" wrote in message
    >>>>>>>>news:6bvaoaF3e31erU3@mid.individual.net...
    >>>>>>>>
    >>>>>>>>
    >>>>>>>>>On Thu, 19 Jun 2008 07:02:54 -0700, Rahul wrote:
    >>>>>>>>>
    >>>>>>>>>
    >>>>>>>>>
    >>>>>>>>>>I just bought a new LiIon Laptop battery for my Dell Inspirion
    >>>>>>>>>>E1505
    >>>>>>>>>>(dual boot WinXP and Fedora).
    >>>>>>>>>>
    >>>>>>>>>>I gave it my initial 10 hour charge. Now what? I started using it
    >>>>>>>>>>but
    >>>>>>>>>>should I continue using it till the battery is drained and then
    >>>>>>>>>>recharge? Or should I only drain it partially? If it is not
    >>>>>>>>>>drained
    >>>>>>>>>>fully how will the Laptop learn (callibrate) itself to what the
    >>>>>>>>>>new
    >>>>>>>>>>capacity is?
    >>>>>>>>>>
    >>>>>>>>>>Or is it recommended that I only partially discharge it? What's
    >>>>>>>>>>best
    >>>>>>>>>>for the battery life?
    >>>>>>>>>>
    >>>>>>>>>>Another point: How many times should I cycle it this way? In the
    >>>>>>>>>>long
    >>>>>>>>>>term should I always wait for a full discharge; or can I chargeit
    >>>>>>>>>>up
    >>>>>>>>>>from a partially-discharged state or does it not matter?
    >>>>>>>>>>
    >>>>>>>>>>I've gogled this but recieve conflicting advice.
    >>>>>>>>>
    >>>>>>>>>From what I've read Li-ion batteries are immune to the 'memory'
    >>>>>>>>>problems of NiCd batteries - it does not really matter much when
    >>>>>>>>>you
    >>>>>>>>>charge them - do what is convenient for you. You should also be
    >>>>>>>>>aware
    >>>>>>>>>that they loose about 10% capacity per year and there is not a
    >>>>>>>>>damned
    >>>>>>>>>thing you can do about it.
    >>>>>>>>
    >>>>>>>>The evidence for this is largely anecdotal. I have batteries that
    >>>>>>>>are
    >>>>>>>>nearly 15 years old which, if this theory were true, would be
    >>>>>>>>useless.
    >>>>>>>
    >>>>>>>Really - I was not aware that rechargable Li-ion batteries had been
    >>>>>>>around
    >>>>>>>that long! So are they really as good as new or only carrying 15% of
    >>>>>>>original charge? Did you do any measurements?
    >>>>>>
    >>>>>>Li-ion batteries have ben around since the early part of the 1990's
    >>>>>>(and
    >>>>>>probably before). The examples cited all exhibit close to their
    >>>>>>original
    >>>>>>capacity (as far as I can tell - they run for near enough the orignal
    >>>>>>time).
    >>>>>>One of the batteries reports that it is only 70% charged after being
    >>>>>>fully charged, but otherwise works as well as the others.
    >>>>>
    >>>>>Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >>>>>the latter just cheaper (just guessing), and still used for economy,or
    >>>>>for some other reason?
    >>>>
    >>>>Nickel-Cadmium batteries are no longer recommended for new products.
    >>>>This
    >>>>is due to environmental concerns of the relatively toxic cadmium. They
    >>>>are
    >>>>available for support of older products that used them. Although Nickel
    >>>>Metal-Hydride appeared as a replacement, they are are not direct
    >>>>replacements in most applications.
    >>>
    >>>
    >>>Interesting - thanks.
    >>>But is this because they weren't available in the identical size
    >>>packages,
    >>>with the same electrical capacity (i.e., voltage, ma-hrs, etc)? Or
    >>>because
    >>>of the external charging circuitry (if any) possibly having different
    >>>requirements?
    >>>
    >>>

    >>
    >>See
    >>http://www.google.com/search?hl=en&q...=Google+Search
    >>and
    >>http://www.servocity.com/html/nicad_...batteries.html

    >
    >
    >



  6. Re: best protocol for carging a Laptop Battery

    "Bill in Co." writes:
    >OK, thanks for the links. There seems to be a set of advantages and
    >disadvantages for each type.


    Don't put too much faith in them. E.g., while self-discharge used to
    be a big problem for NiMH batteries (and still is if you buy the wrong
    ones), there are now low-discharge variants of NiMH batteries (e.g.,
    Sanyo Eneloop) where that problem is solved.

    - anton
    --
    M. Anton Ertl Some things have to be seen to be believed
    anton@mips.complang.tuwien.ac.at Most things have to be believed to be seen
    http://www.complang.tuwien.ac.at/anton/home.html

  7. Re: best protocol for carging a Laptop Battery

    anton@mips.complang.tuwien.ac.at (Anton Ertl) writes:
    >"Bill in Co." writes:
    >>OK, thanks for the links. There seems to be a set of advantages and
    >>disadvantages for each type.

    >
    >Don't put too much faith in them. E.g., while self-discharge used to
    >be a big problem for NiMH batteries (and still is if you buy the wrong
    >ones), there are now low-discharge variants of NiMH batteries (e.g.,
    >Sanyo Eneloop) where that problem is solved.


    http://en.wikipedia.org/wiki/NiMH
    http://en.wikipedia.org/wiki/Nickel-cadmium_battery

    look more up-to-date to me than the stuff found through the links
    further up in this thread.

    - anton
    --
    M. Anton Ertl Some things have to be seen to be believed
    anton@mips.complang.tuwien.ac.at Most things have to be believed to be seen
    http://www.complang.tuwien.ac.at/anton/home.html

  8. Re: best protocol for carging a Laptop Battery


    "Bill in Co." wrote in message
    news:OhWs6Fd1IHA.2208@TK2MSFTNGP04.phx.gbl...
    > M.I.5¾ wrote:
    >> "Bill in Co." wrote in message
    >> news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>> M.I.5¾ wrote:
    >>>> "ray" wrote in message
    >>>> news:6c1utvF3e9107U4@mid.individual.net...
    >>>>> On Fri, 20 Jun 2008 07:55:55 +0100, M.I.5Y wrote:
    >>>>>
    >>>>>> "ray" wrote in message
    >>>>>> news:6bvaoaF3e31erU3@mid.individual.net...
    >>>>>>> On Thu, 19 Jun 2008 07:02:54 -0700, Rahul wrote:
    >>>>>>>
    >>>>>>>> I just bought a new LiIon Laptop battery for my Dell Inspirion
    >>>>>>>> E1505
    >>>>>>>> (dual boot WinXP and Fedora).
    >>>>>>>>
    >>>>>>>> I gave it my initial 10 hour charge. Now what? I started using it
    >>>>>>>> but
    >>>>>>>> should I continue using it till the battery is drained and then
    >>>>>>>> recharge? Or should I only drain it partially? If it is not drained
    >>>>>>>> fully how will the Laptop learn (callibrate) itself to what the new
    >>>>>>>> capacity is?
    >>>>>>>>
    >>>>>>>> Or is it recommended that I only partially discharge it? What's
    >>>>>>>> best
    >>>>>>>> for the battery life?
    >>>>>>>>
    >>>>>>>> Another point: How many times should I cycle it this way? In the
    >>>>>>>> long
    >>>>>>>> term should I always wait for a full discharge; or can I charge it
    >>>>>>>> up
    >>>>>>>> from a partially-discharged state or does it not matter?
    >>>>>>>>
    >>>>>>>> I've gogled this but recieve conflicting advice.
    >>>>>>>
    >>>>>>> From what I've read Li-ion batteries are immune to the 'memory'
    >>>>>>> problems of NiCd batteries - it does not really matter much when you
    >>>>>>> charge them - do what is convenient for you. You should also be
    >>>>>>> aware
    >>>>>>> that they loose about 10% capacity per year and there is not a
    >>>>>>> damned
    >>>>>>> thing you can do about it.
    >>>>>>
    >>>>>> The evidence for this is largely anecdotal. I have batteries that
    >>>>>> are
    >>>>>> nearly 15 years old which, if this theory were true, would be
    >>>>>> useless.
    >>>>>
    >>>>> Really - I was not aware that rechargable Li-ion batteries had been
    >>>>> around
    >>>>> that long! So are they really as good as new or only carrying 15% of
    >>>>> original charge? Did you do any measurements?
    >>>>
    >>>> Li-ion batteries have ben around since the early part of the 1990's
    >>>> (and
    >>>> probably before). The examples cited all exhibit close to their
    >>>> original
    >>>> capacity (as far as I can tell - they run for near enough the orignal
    >>>> time).
    >>>> One of the batteries reports that it is only 70% charged after being
    >>>> fully charged, but otherwise works as well as the others.
    >>>
    >>> Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >>> the latter just cheaper (just guessing), and still used for economy, or
    >>> for some other reason?

    >>
    >> Nickel-Cadmium batteries are no longer recommended for new products.
    >> This
    >> is due to environmental concerns of the relatively toxic cadmium. They
    >> are
    >> available for support of older products that used them. Although Nickel
    >> Metal-Hydride appeared as a replacement, they are are not direct
    >> replacements in most applications.

    >
    > Interesting - thanks.
    > But is this because they weren't available in the identical size packages,
    > with the same electrical capacity (i.e., voltage, ma-hrs, etc)? Or
    > because of the external charging circuitry (if any) possibly having
    > different requirements?


    Although the electrical characteristics are pretty similar (apart from the
    greatly increased mAh capacity), Ni-MH has an exothermic charge reaction
    (Ni-Cd was endothermic). This means that when rapid charging the cells, it
    is necessary to have temperature monitoring and cutout which was unnecesary
    with Ni-Cd. However, a temperature sensor could be used to detect the end
    of charge condition for Ni-Cd (as the charge power had to be disipated as
    heat once the battery stopped absorbing it's charge). This cannot be so
    easily done in Ni-MH as the cells get warm anyway.



  9. Re: best protocol for carging a Laptop Battery

    M.I.5¾ wrote:
    > "Bill in Co." wrote in message
    > news:OhWs6Fd1IHA.2208@TK2MSFTNGP04.phx.gbl...
    >> M.I.5¾ wrote:
    >>> "Bill in Co." wrote in message
    >>> news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>>> M.I.5¾ wrote:
    >>>>> "ray" wrote in message
    >>>>> news:6c1utvF3e9107U4@mid.individual.net...
    >>>>>> On Fri, 20 Jun 2008 07:55:55 +0100, M.I.5Y wrote:
    >>>>>>
    >>>>>>> "ray" wrote in message
    >>>>>>> news:6bvaoaF3e31erU3@mid.individual.net...
    >>>>>>>> On Thu, 19 Jun 2008 07:02:54 -0700, Rahul wrote:
    >>>>>>>>
    >>>>>>>>> I just bought a new LiIon Laptop battery for my Dell Inspirion
    >>>>>>>>> E1505 (dual boot WinXP and Fedora).
    >>>>>>>>>
    >>>>>>>>> I gave it my initial 10 hour charge. Now what? I started using it
    >>>>>>>>> but should I continue using it till the battery is drained and
    >>>>>>>>> then
    >>>>>>>>> recharge? Or should I only drain it partially? If it is not
    >>>>>>>>> drained
    >>>>>>>>> fully how will the Laptop learn (callibrate) itself to what the
    >>>>>>>>> new
    >>>>>>>>> capacity is?
    >>>>>>>>>
    >>>>>>>>> Or is it recommended that I only partially discharge it? What's
    >>>>>>>>> best for the battery life?
    >>>>>>>>>
    >>>>>>>>> Another point: How many times should I cycle it this way? In the
    >>>>>>>>> long term should I always wait for a full discharge; or can I
    >>>>>>>>> charge it
    >>>>>>>>> up from a partially-discharged state or does it not matter?
    >>>>>>>>>
    >>>>>>>>> I've gogled this but recieve conflicting advice.
    >>>>>>>>
    >>>>>>>> From what I've read Li-ion batteries are immune to the 'memory'
    >>>>>>>> problems of NiCd batteries - it does not really matter much when
    >>>>>>>> you
    >>>>>>>> charge them - do what is convenient for you. You should also be
    >>>>>>>> aware that they loose about 10% capacity per year and there is not
    >>>>>>>> a
    >>>>>>>> damned thing you can do about it.
    >>>>>>>
    >>>>>>> The evidence for this is largely anecdotal. I have batteries that
    >>>>>>> are nearly 15 years old which, if this theory were true, would be
    >>>>>>> useless.
    >>>>>>
    >>>>>> Really - I was not aware that rechargable Li-ion batteries had been
    >>>>>> around
    >>>>>> that long! So are they really as good as new or only carrying 15% of
    >>>>>> original charge? Did you do any measurements?
    >>>>>
    >>>>> Li-ion batteries have ben around since the early part of the 1990's
    >>>>> (and
    >>>>> probably before). The examples cited all exhibit close to their
    >>>>> original
    >>>>> capacity (as far as I can tell - they run for near enough the orignal
    >>>>> time).
    >>>>> One of the batteries reports that it is only 70% charged after being
    >>>>> fully charged, but otherwise works as well as the others.
    >>>>
    >>>> Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >>>> the latter just cheaper (just guessing), and still used for economy, or
    >>>> for some other reason?
    >>>
    >>> Nickel-Cadmium batteries are no longer recommended for new products.
    >>> This is due to environmental concerns of the relatively toxic cadmium.
    >>> They
    >>> are available for support of older products that used them. Although
    >>> Nickel
    >>> Metal-Hydride appeared as a replacement, they are are not direct
    >>> replacements in most applications.

    >>
    >> Interesting - thanks.
    >> But is this because they weren't available in the identical size
    >> packages,
    >> with the same electrical capacity (i.e., voltage, ma-hrs, etc)? Or
    >> because of the external charging circuitry (if any) possibly having
    >> different requirements?

    >
    > Although the electrical characteristics are pretty similar (apart from the
    > greatly increased mAh capacity), Ni-MH has an exothermic charge reaction
    > (Ni-Cd was endothermic). This means that when rapid charging the cells,
    > it
    > is necessary to have temperature monitoring and cutout which was
    > unnecesary
    > with Ni-Cd.


    Interesting. And what a pain...

    > However, a temperature sensor could be used to detect the end
    > of charge condition for Ni-Cd (as the charge power had to be disipated as
    > heat once the battery stopped absorbing it's charge). This cannot be so
    > easily done in Ni-MH as the cells get warm anyway.


    I would have thought the end of charge condition (for any battery) could
    have been sensed by a dropoff in the charging current when the battery is
    nearly fully charged.
    If, for example, one used a fixed charging voltage source, and charged the
    battery through a resistor, the current would start off high, and then drop
    as the battery got charged. Apparently they don't do it that way.



  10. Re: best protocol for carging a Laptop Battery

    "Bill in Co." writes:

    > M.I.5¾ wrote:
    >> "Bill in Co." wrote in message
    >> news:OhWs6Fd1IHA.2208@TK2MSFTNGP04.phx.gbl...
    >>> M.I.5¾ wrote:
    >>>> "Bill in Co." wrote in message
    >>>> news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>>>> Have the Li-ion batteries essentially replaced the NiCad ones? Or are
    >>>>> the latter just cheaper (just guessing), and still used for economy, or
    >>>>> for some other reason?
    >>>>
    >>>> Nickel-Cadmium batteries are no longer recommended for new
    >>>> products. This is due to environmental concerns of the
    >>>> relatively toxic cadmium. They are available for support of older
    >>>> products that used them. Although Nickel Metal-Hydride appeared
    >>>> as a replacement, they are are not direct replacements in most
    >>>> applications.
    >>>
    >>> Interesting - thanks.
    >>> But is this because they weren't available in the identical size
    >>> packages, with the same electrical capacity (i.e., voltage,
    >>> ma-hrs, etc)? Or because of the external charging circuitry (if
    >>> any) possibly having different requirements?

    >>
    >> Although the electrical characteristics are pretty similar (apart
    >> from the greatly increased mAh capacity), Ni-MH has an exothermic
    >> charge reaction (Ni-Cd was endothermic). This means that when
    >> rapid charging the cells, it is necessary to have temperature
    >> monitoring and cutout which was unnecesary with Ni-Cd.

    >
    > Interesting. And what a pain...
    >
    >> However, a temperature sensor could be used to detect the end of
    >> charge condition for Ni-Cd (as the charge power had to be disipated
    >> as heat once the battery stopped absorbing it's charge). This
    >> cannot be so easily done in Ni-MH as the cells get warm anyway.

    >
    > I would have thought the end of charge condition (for any battery) could
    > have been sensed by a dropoff in the charging current when the battery is
    > nearly fully charged.
    > If, for example, one used a fixed charging voltage source, and charged the
    > battery through a resistor, the current would start off high, and then drop
    > as the battery got charged. Apparently they don't do it that way.


    Both NiCd and NiMH cells are charged with a constant current. A
    slight drop in cell voltage, at least with NiMH, indicates full
    charge.

    --
    Måns Rullgård
    mans@mansr.com

  11. Re: best protocol for carging a Laptop Battery

    Måns Rullgård wrote:
    > "Bill in Co." writes:
    >
    >> M.I.5¾ wrote:
    >>> "Bill in Co." wrote in message
    >>> news:OhWs6Fd1IHA.2208@TK2MSFTNGP04.phx.gbl...
    >>>> M.I.5¾ wrote:
    >>>>> "Bill in Co." wrote in message
    >>>>> news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>>>>> Have the Li-ion batteries essentially replaced the NiCad ones? Or
    >>>>>> are
    >>>>>> the latter just cheaper (just guessing), and still used for economy,
    >>>>>> or
    >>>>>> for some other reason?
    >>>>>
    >>>>> Nickel-Cadmium batteries are no longer recommended for new
    >>>>> products. This is due to environmental concerns of the
    >>>>> relatively toxic cadmium. They are available for support of older
    >>>>> products that used them. Although Nickel Metal-Hydride appeared
    >>>>> as a replacement, they are are not direct replacements in most
    >>>>> applications.
    >>>>
    >>>> Interesting - thanks.
    >>>> But is this because they weren't available in the identical size
    >>>> packages, with the same electrical capacity (i.e., voltage,
    >>>> ma-hrs, etc)? Or because of the external charging circuitry (if
    >>>> any) possibly having different requirements?
    >>>
    >>> Although the electrical characteristics are pretty similar (apart
    >>> from the greatly increased mAh capacity), Ni-MH has an exothermic
    >>> charge reaction (Ni-Cd was endothermic). This means that when
    >>> rapid charging the cells, it is necessary to have temperature
    >>> monitoring and cutout which was unnecesary with Ni-Cd.

    >>
    >> Interesting. And what a pain...
    >>
    >>> However, a temperature sensor could be used to detect the end of
    >>> charge condition for Ni-Cd (as the charge power had to be disipated
    >>> as heat once the battery stopped absorbing it's charge). This
    >>> cannot be so easily done in Ni-MH as the cells get warm anyway.

    >>
    >> I would have thought the end of charge condition (for any battery) could
    >> have been sensed by a dropoff in the charging current when the battery is
    >> nearly fully charged.
    >> If, for example, one used a fixed charging voltage source, and charged
    >> the
    >> battery through a resistor, the current would start off high, and then
    >> drop
    >> as the battery got charged. Apparently they don't do it that way.

    >
    > Both NiCd and NiMH cells are charged with a constant current. A
    > slight drop in cell voltage, at least with NiMH, indicates full charge.
    >
    > --
    > Måns Rullgård
    > mans@mansr.com


    OK, with later retrospect, I was guessing that might be the way they
    actually do it, since it's probably safer (since there is no huge initial
    current inrush, like there would be for a dead battery).

    But the problem with that method is that you can't tell when its fully
    charged as easily as you could if you were to use the constant voltage
    source method (and just monitor the charging current), from what I can see.



  12. Re: best protocol for carging a Laptop Battery

    > Måns Rullgård wrote:
    >> "Bill in Co." writes:
    >>
    >>> M.I.5¾ wrote:
    >>>> "Bill in Co." wrote in message
    >>>> news:OhWs6Fd1IHA.2208@TK2MSFTNGP04.phx.gbl...
    >>>>> M.I.5¾ wrote:
    >>>>>> "Bill in Co." wrote in message
    >>>>>> news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>>>>>> Have the Li-ion batteries essentially replaced the NiCad ones? Or
    >>>>>>> are the latter just cheaper (just guessing), and still used for
    >>>>>>> economy,
    >>>>>>> or for some other reason?
    >>>>>>
    >>>>>> Nickel-Cadmium batteries are no longer recommended for new
    >>>>>> products. This is due to environmental concerns of the
    >>>>>> relatively toxic cadmium. They are available for support of older
    >>>>>> products that used them. Although Nickel Metal-Hydride appeared
    >>>>>> as a replacement, they are are not direct replacements in most
    >>>>>> applications.
    >>>>>
    >>>>> Interesting - thanks.
    >>>>> But is this because they weren't available in the identical size
    >>>>> packages, with the same electrical capacity (i.e., voltage,
    >>>>> ma-hrs, etc)? Or because of the external charging circuitry (if
    >>>>> any) possibly having different requirements?
    >>>>
    >>>> Although the electrical characteristics are pretty similar (apart
    >>>> from the greatly increased mAh capacity), Ni-MH has an exothermic
    >>>> charge reaction (Ni-Cd was endothermic). This means that when
    >>>> rapid charging the cells, it is necessary to have temperature
    >>>> monitoring and cutout which was unnecesary with Ni-Cd.
    >>>
    >>> Interesting. And what a pain...
    >>>
    >>>> However, a temperature sensor could be used to detect the end of
    >>>> charge condition for Ni-Cd (as the charge power had to be disipated
    >>>> as heat once the battery stopped absorbing it's charge). This
    >>>> cannot be so easily done in Ni-MH as the cells get warm anyway.
    >>>
    >>> I would have thought the end of charge condition (for any battery) could
    >>> have been sensed by a dropoff in the charging current when the battery
    >>> is
    >>> nearly fully charged.
    >>> If, for example, one used a fixed charging voltage source, and charged
    >>> the battery through a resistor, the current would start off high, and
    >>> then
    >>> drop as the battery got charged. Apparently they don't do it that way.

    >>
    >> Both NiCd and NiMH cells are charged with a constant current. A
    >> slight drop in cell voltage, at least with NiMH, indicates full charge.
    >>
    >> --
    >> Måns Rullgård
    >> mans@mansr.com


    OK, with later retrospect, I was guessing that might be the way they
    actually do it, since it's perhaps a bit safer (since there is no large
    initial
    current inrush like there would be for a dead battery). But....

    But the problem with that method (constant current charging) is that you
    can't tell when
    the battery is fully charged as well as you could if you were to use the
    constant voltage
    source (with a series resistor) method, and monitor the charging current
    (from I what I can see).

    So I still don't see why they don't do it this way.



  13. Re: best protocol for carging a Laptop Battery


    "Bill in Co." wrote in message
    news:uxvMNKI3IHA.1428@TK2MSFTNGP06.phx.gbl...
    >> Måns Rullgård wrote:
    >>> "Bill in Co." writes:
    >>>
    >>>> M.I.5¾ wrote:
    >>>>> "Bill in Co." wrote in message
    >>>>> news:OhWs6Fd1IHA.2208@TK2MSFTNGP04.phx.gbl...
    >>>>>> M.I.5¾ wrote:
    >>>>>>> "Bill in Co." wrote in message
    >>>>>>> news:eINmqSZ1IHA.3756@TK2MSFTNGP04.phx.gbl...
    >>>>>>>> Have the Li-ion batteries essentially replaced the NiCad ones? Or
    >>>>>>>> are the latter just cheaper (just guessing), and still used for
    >>>>>>>> economy,
    >>>>>>>> or for some other reason?
    >>>>>>>
    >>>>>>> Nickel-Cadmium batteries are no longer recommended for new
    >>>>>>> products. This is due to environmental concerns of the
    >>>>>>> relatively toxic cadmium. They are available for support of older
    >>>>>>> products that used them. Although Nickel Metal-Hydride appeared
    >>>>>>> as a replacement, they are are not direct replacements in most
    >>>>>>> applications.
    >>>>>>
    >>>>>> Interesting - thanks.
    >>>>>> But is this because they weren't available in the identical size
    >>>>>> packages, with the same electrical capacity (i.e., voltage,
    >>>>>> ma-hrs, etc)? Or because of the external charging circuitry (if
    >>>>>> any) possibly having different requirements?
    >>>>>
    >>>>> Although the electrical characteristics are pretty similar (apart
    >>>>> from the greatly increased mAh capacity), Ni-MH has an exothermic
    >>>>> charge reaction (Ni-Cd was endothermic). This means that when
    >>>>> rapid charging the cells, it is necessary to have temperature
    >>>>> monitoring and cutout which was unnecesary with Ni-Cd.
    >>>>
    >>>> Interesting. And what a pain...
    >>>>
    >>>>> However, a temperature sensor could be used to detect the end of
    >>>>> charge condition for Ni-Cd (as the charge power had to be disipated
    >>>>> as heat once the battery stopped absorbing it's charge). This
    >>>>> cannot be so easily done in Ni-MH as the cells get warm anyway.
    >>>>
    >>>> I would have thought the end of charge condition (for any battery)
    >>>> could
    >>>> have been sensed by a dropoff in the charging current when the battery
    >>>> is
    >>>> nearly fully charged.
    >>>> If, for example, one used a fixed charging voltage source, and charged
    >>>> the battery through a resistor, the current would start off high, and
    >>>> then
    >>>> drop as the battery got charged. Apparently they don't do it that
    >>>> way.
    >>>
    >>> Both NiCd and NiMH cells are charged with a constant current. A
    >>> slight drop in cell voltage, at least with NiMH, indicates full charge.
    >>>
    >>> --
    >>> Måns Rullgård
    >>> mans@mansr.com

    >
    > OK, with later retrospect, I was guessing that might be the way they
    > actually do it, since it's perhaps a bit safer (since there is no large
    > initial
    > current inrush like there would be for a dead battery). But....
    >
    > But the problem with that method (constant current charging) is that you
    > can't tell when
    > the battery is fully charged as well as you could if you were to use the
    > constant voltage
    > source (with a series resistor) method, and monitor the charging current
    > (from I what I can see).
    >
    > So I still don't see why they don't do it this way.


    Actually modern charge monitoring circuits have got quite sophisticated, and
    are quite adept at detecting end of charge condition using the electrical
    characteristics of the cells. However, the best of them still use some form
    of temperature monitoring as an extra clue.



  14. Re: best protocol for carging a Laptop Battery


    "Bill in Co." wrote in message
    news:OCmRq2j1IHA.5048@TK2MSFTNGP06.phx.gbl...
    > OK, thanks for the links. There seems to be a set of advantages and
    > disadvantages for each type.
    >


    The two main differences that affect choice are:

    Mi-MH: Has a greater capacity per unit volume (at least 4 times these days -
    and rising). Because they are lighter, an even greater energy capacity per
    unit weight.

    Ni-Cd: Can deliver very high discharge currents with practically no loss of
    capacity. They can even deliver what might be regarded as short circuit
    currents with little damage. Ni-MH suffer damage with even moderately high
    currents (but even this is improving as we type).




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