"M.I.5¾" <no.one@no.where.NO_SPAM.co.uk> wrote in
news:4ab754c4$1_1@glkas0286.greenlnk.net:

> I have batteries that are 15 years old that have been treated by
> ignoring your rubbish advice. Indeed I've never seen any of the
> rubbish you've spouted before and I work in the Aerospace industry
> where we use a lot of batteries of many chemistries. There is
> currently no li-ion technology that will last for 1300 full charge and
> discharge cycles. The one unfortunate aspect of the technology is
> that it does have the lowest charge/discharge capability of any
> recognised rechargeable chemistry (typically 300-500 full cycles)
>

I'm curious. How do you get along in the industry acting like an asshole
to every person you disagree with? This isn't about batteries, but do you
always attack fellow employees you disagree with in this manner...or just
on usenet and chatroom where you're out of punching range?

I can't believe some supervisor hasn't notice your horrible attitude and
simply sacked your acid ass to keep the peace, raising moral in any
environment by 50%.


--
Larry

"BillW50" <BillW50@aol.kom> schreef in bericht
news:h95to0$sc0$1@news.eternal-september.org...
> In news:4ab6745e$0$83248$e4fe514c@news.xs4all.nl,
> Linea Recta typed on Sun, 20 Sep 2009 20:27:39 +0200:
>> "BillW50" <BillW50@aol.kom> schreef in bericht
>> news:h95ed7$es$1@news.eternal-september.org...
>>> In news:4ab6318a$0$83248$e4fe514c@news.xs4all.nl,
>>> Linea Recta typed on Sun, 20 Sep 2009 15:43:35 +0200:
>>>> In the past I have replaced the CMOS power cell of my PC, but I was
>>>> wondering how is this done in a laptop? Is the cell accessible at
>>>> all?
>>>
>>> Most laptops and netbooks use Ni-HM batteries for the CMOS/RTC which
>>> the computer routinely recharges.
>>
>> Formerly I thought CMOS batteries op PC were recharged, but then I
>> learned, for some reason, this is not the case. So what's the logic
>> to do so only for laptops?
>
> I am not sure. As desktops could be designed with a rechargeable and
> laptops with a disposable. But it isn't generally the case. Maybe
> because most people can take a desktop apart while most can't handle a
> laptop disassembly I guess.
>
>>> They rarely fail so I wouldn't worry too
>>> much about them. I would worry more about the florescent lamp,
>>> inverter, hard drive, and main battery myself. Although if you are
>>> still interested, it usually requires total disassembly to get to it.
>>
>> I've already taken out the main battery to increase its lifespan.
>
> That is a very good idea. Some claim you should use them every 2 months


That's about the scheme I follow.


> or so to keep the capacity up. Although I haven't really seen any
> evidence this is necessary. M.I.5¾ claims this by the way.
>
> Do you also monitor the CPU and drive temps? The CPU temp monitoring
> will let you know when it is time to do some dust bunny cleaning. <vbg>


Yes, and I noticed that the graphics temperature is rather high (62 Celcius)
(from the beginning. The laptop is quite new, so shouldn't be dusty yet).
Besides, how is a laptop accessible for dust cleaning?

Everest report:
----------------------------------------------------------------
Veld Waarde
Sensoreigenschappen
Sensortype CPU, HDD, ACPI
GPU sensortype Driver (NV-DRV)

Temperaturen
CPU 47 °C (117 °F)
CPU #1 / Kern #1 50 °C (122 °F)
CPU #1 / Kern #2 50 °C (122 °F)
GPU 62 °C (144 °F)
WDC WD2500BEVS-22UST0 29 °C (84 °F)

Spanningswaarde
CPU Core 1.16 V
----------------------------------------------------------------



--
regards,

|\ /|
| \/ |@rk
\../
\/os

"Larry" <noone@home.com> schreef in bericht
news:Xns9C8C9D3378E2Anoonehomecom@74.209.131.13...
> "Linea Recta" <mccm.vos@abc.invalid> wrote in news:4ab6745e$0$83248
> $e4fe514c@news.xs4all.nl:
>
>> I've already taken out the main battery to increase its lifespan.
>>
>>
>
> Totally unnecessary. Simply leave the laptop plugged in every chance
> you get. Lithium-Ion and Lithium-Polymer batteries are float batteries,
> unlike Ni-Cd and Ni-Mh cells. If you never discharge them below 80%,
> and recharge them as soon as you can, they'll last for thousands of
> charges. Deep discharging is so destructive, every battery has a
> specially programmed IC in it to PREVENT you from discharging them below
> 50%. That's when the IC tells the computer to shut down to protect the
> battery pack from ultimate destruction.


I thought the purpose of this mechanism was to prevent dataloss...


>
> There is, and always has been, a problem with the IC and its
> programming. What the IC THINKS is the current charge state of the pack
> and what the REAL charge state of the pack is grow constantly wider
> apart because the programming of the IC is an average for cells of this
> type and the cells in your pack aren't average. So, every so often, I
> like 2 months as a yardstick because my computer is discharged daily,
> you need to "cycle" the battery pack to the point where the IC shuts
> down the pack ("dead"), then IMMEDIATELY recharge the pack for a minimum
> of 16 hours of continuous charging so the IC can find the point of full
> charge, which it measures as a sudden rise of cell voltage under
> charging current. A finishing charge, after the main high current
> charge, is what takes so long and should not be disturbed. The IC will
> shut down the charge, completely, to prevent overcharging which makes
> these wonder batteries explode quite violently because cell warpage
> results in internal shorting to hundreds of amps for a few
> seconds..BOOM!


Yes I've heard such stories, but never experienced an explosion myself yet.
But I suppose it's always best NOT to leave any devices charging while
leaving home. Exept perhaps if one has very good fire insurance.


>
> So, run it until it's dead every couple of months, then IMMEDIATELY
> recharge for a minimum of 16 hours uninterrupted. All other times,


That's the way I used it in the beginning (as also indicated in the manual).
Though I want to point out that it certainly doesn't take 16 hours before
fully charges again! I estimate this takes about 3 hours at the most.



> recharge it as quickly as you can find a power outlet to do so, and as
> often as you can to reduce the destruction deep cycling causes. You get
> many years of service out of them. This same method is also very useful
> in your cellular and other Lithium-powered rechargeable devices.
>
> If you store the battery pack for over 2 weeks without use, run the
> laptop until the IC shuts down the laptop on discharge, then give it the
> full 16 hour recharge cycle IMMEDIATELY, to reset the IC before you
> start using the pack again. Lithium packs self-discharge something
> awful as they leak like hell inside just sitting there, the nature of
> the beast. The IC timer gets lost if it just sits and self-discharges.
> Notice your initial instruction was to recharge the computer for 16-20
> hours the day you got it...before using it to prevent you going really
> deep in discharge from a confused charge IC allowing it to go way too
> far. You ignored it, of course, everyone does and did initial damage to
> a brand new battery pack the day you got it.....
>
> Case in point....for any critics......
>
> I have a Digital Mind Corporation (DMC) Xclef 500 120GB hard drive MP3
> player/recorder/FM Radio:
> http://pocketnow.com/review/digital-...-dmc-xclef-500
>
> It's an antique by mp3 player standards. It even outlived the company!
> I bought it the 2nd week it was offered for sale in the USA. Last
> month, as I noticed its runtime of 22 hours was down to 10, I tore it
> apart and replaced it 4/3 C cell Li-Ion 2000maH cell with a newfangled
> 4/3 C cell Li-Polymer 2800maH cell. Bought in early 2004, that's over 5
> years of hard use as it's my main MP3 player in my work truck. I rest
> my case about this method of making Lithium rechargeables have long
> lives. 5 days/week x 52 weeks x 5 years = 1300 usage cycles, give or
> take a few hundred as it was also used on weekends a lot.
>
> This battery was so old, the charge controller was a separate PC board
> held into the end of it by the shrinkwrap case. I had to move that
> board to the new cell as I had to make my own battery pack. Works
> great! Will now run about 30 hours continuously!
>
> By the way, looking at the webpages, this monster player seems to be
> still available with various drive sizes in it if you want a great
> player without the glitz. The drives are standard 2.5" laptop drives
> available anywhere and the OS supports up to one 137GB FAT16 partition.
> Mine had a 40GB drive in it, initially, but a friend upgraded his big
> laptop from 120GB to something much larger so gave me this 120GB Toshiba
> drive. I reformatted it in a laptop and simply plugged it into the
> Xclef HD-500 player. If you tell it to simply random play the entire
> drive, I'm not sure how many thousands of hours that is, now..(c;] The
> player has no copy protection games. You simply plug it into any
> computer and it is recognized as an external USB hard drive by PC, Mac
> or Linux boxes. As a USB drive, you can put any files on or off it with
> any file manager, even a DOS window. No funny business. A great use
> for it is as an extra, SELF-BATTERY-POWERED, hard drive for your
> netbook! It uses no power from your netbook battery, unlike other USB
> portable drives, so your runtime is the same. It runs much longer than
> even my extended runtime, 9-cell Samsung NC10 is capable of running, so
> just recharge it when you recharge the netbook and you have nearly
> doubled your storage on a removable drive that's very easy to
> load...with anything, not just music....(c;]
>


Thanks very much for the info.


--
regards,

|\ /|
| \/ |@rk
\../
\/os

"Barry Watzman" <WatzmanNOSPAM@neo.rr.com> schreef in bericht
news:h95v2q$abf$1@aioe.org...
> "Power Cell"? You mean battery?
>
> ???


Indeed, the mainboard manual states "CR2032 3V lithium Cell CMOS Power". To
prevent confusion with what is called main "battery".



>
> The CMOS batteries of laptops vary widely. Some are single use, some are
> rechargeable. Some are "stock", some are custom. Some plug in, some are
> soldered in. Some are accessible easily, some with moderate difficulty,
> on some you have to remove the motherboard from the case (e.g. battery on
> the bottom of the motherboard with no access cover provided).


My PC's coin cell (that's the word I should have used) can be replaced
easily. But even if it would be soldered, I'd solder it out.
But for laptops my main concern would be how to open it in the first place,
of course without ruining the case.



--
regards,

|\ /|
| \/ |@rk
\../
\/os

"Linea Recta" <mccm.vos@abc.invalid> schreef in bericht
news:4ab7cc59$0$83250$e4fe514c@news.xs4all.nl...
>
> "BillW50" <BillW50@aol.kom> schreef in bericht
> news:h95to0$sc0$1@news.eternal-september.org...
>> In news:4ab6745e$0$83248$e4fe514c@news.xs4all.nl,
>> Linea Recta typed on Sun, 20 Sep 2009 20:27:39 +0200:
>>> "BillW50" <BillW50@aol.kom> schreef in bericht
>>> news:h95ed7$es$1@news.eternal-september.org...
>>>> In news:4ab6318a$0$83248$e4fe514c@news.xs4all.nl,
>>>> Linea Recta typed on Sun, 20 Sep 2009 15:43:35 +0200:
>>>>> In the past I have replaced the CMOS power cell of my PC, but I was
>>>>> wondering how is this done in a laptop? Is the cell accessible at
>>>>> all?
>>>>
>>>> Most laptops and netbooks use Ni-HM batteries for the CMOS/RTC which
>>>> the computer routinely recharges.
>>>
>>> Formerly I thought CMOS batteries op PC were recharged, but then I
>>> learned, for some reason, this is not the case. So what's the logic
>>> to do so only for laptops?
>>
>> I am not sure. As desktops could be designed with a rechargeable and
>> laptops with a disposable. But it isn't generally the case. Maybe
>> because most people can take a desktop apart while most can't handle a
>> laptop disassembly I guess.
>>
>>>> They rarely fail so I wouldn't worry too
>>>> much about them. I would worry more about the florescent lamp,
>>>> inverter, hard drive, and main battery myself. Although if you are
>>>> still interested, it usually requires total disassembly to get to it.
>>>
>>> I've already taken out the main battery to increase its lifespan.
>>
>> That is a very good idea. Some claim you should use them every 2 months
>
>
> That's about the scheme I follow.
>
>
>> or so to keep the capacity up. Although I haven't really seen any
>> evidence this is necessary. M.I.5¾ claims this by the way.
>>
>> Do you also monitor the CPU and drive temps? The CPU temp monitoring
>> will let you know when it is time to do some dust bunny cleaning. <vbg>
>
>
> Yes, and I noticed that the graphics temperature is rather high (62
> Celcius)


Update: 72 degrees Celcius half an hour after switching on...



--
regards,

|\ /|
| \/ |@rk
\../
\/os

"Larry" <noone@home.com> wrote in message
news:Xns9C8D80BA0BA31noonehomecom@74.209.131.13...
> "M.I.5¾" <no.one@no.where.NO_SPAM.co.uk> wrote in
> news:4ab754c4$1_1@glkas0286.greenlnk.net:
>
>> Complete rubbish! It is the laptop internally generated heat that
>> destroys the batteries when you leave them in.
>>
>
> You must be using a MAC. REAL laptops have EXTERNAL and CHANGEABLE
> batteries that are on the OUTSIDE of them....for a reason....
>
>

How dare you.

I wouldn't use that ****.

"Larry" <noone@home.com> wrote in message
news:Xns9C8D82640DACFnoonehomecom@74.209.131.13...
> "M.I.5¾" <no.one@no.where.NO_SPAM.co.uk> wrote in
> news:4ab754c4$1_1@glkas0286.greenlnk.net:
>
>> Where did you get all this garbage about no discharging li-ion
>> batteries below 80%? Li-ion batteries are designed to be discharged
>> and charged. There is a lower limit but its 0% charge (which is
>> regarded as being 2.8 volts per cell (2.5 volts for some Sony
>> designs)). Most equipment uses 3.0 volts as 0% to avoid the problems
>> with over discharge. Battery controllers do not prevent cells being
>> discharged below 50% and I regularly discharge li-ion batteries to
>> near 0% (or even 0%). Most laptops are set up to shut the machine
>> down at or around 5%, but this is something Windows does rather than
>> the controller.
>>
>>
>
> http://batteryuniversity.com/
>
> http://www.batteryuniversity.com/partone-5.htm
>

There is no such organisation as Battery University (and why would there
be?). That web site is run by an individual who just trawls garbage like
yours from the internet and presents it as an authoritative guide.

At least one gem of wisdom on his site was deliberately planted for him for
him to find and include. That he did had the unexpected result that the
feature appeared in a generation of iPAQ hand helds.

"Larry" <noone@home.com> wrote in message
news:Xns9C8D82F7C1406noonehomecom@74.209.131.13...
> "M.I.5¾" <no.one@no.where.NO_SPAM.co.uk> wrote in
> news:4ab754c4$1_1@glkas0286.greenlnk.net:
>
>> I have batteries that are 15 years old that have been treated by
>> ignoring your rubbish advice. Indeed I've never seen any of the
>> rubbish you've spouted before and I work in the Aerospace industry
>> where we use a lot of batteries of many chemistries. There is
>> currently no li-ion technology that will last for 1300 full charge and
>> discharge cycles. The one unfortunate aspect of the technology is
>> that it does have the lowest charge/discharge capability of any
>> recognised rechargeable chemistry (typically 300-500 full cycles)
>>
>
> I'm curious. How do you get along in the industry acting like an asshole
> to every person you disagree with? This isn't about batteries, but do you
> always attack fellow employees you disagree with in this manner...or just
> on usenet and chatroom where you're out of punching range?
>
> I can't believe some supervisor hasn't notice your horrible attitude and
> simply sacked your acid ass to keep the peace, raising moral in any
> environment by 50%.
>

Your post was 100% garbage. I point it out. Get used to it.

"Linea Recta" <mccm.vos@abc.invalid> wrote in message
news:4ab7cfe8$0$83251$e4fe514c@news.xs4all.nl...
>
> "Larry" <noone@home.com> schreef in bericht
> news:Xns9C8C9D3378E2Anoonehomecom@74.209.131.13...
>> "Linea Recta" <mccm.vos@abc.invalid> wrote in news:4ab6745e$0$83248
>> $e4fe514c@news.xs4all.nl:
>>
>>> I've already taken out the main battery to increase its lifespan.
>>>
>>>
>>
>> Totally unnecessary. Simply leave the laptop plugged in every chance
>> you get. Lithium-Ion and Lithium-Polymer batteries are float batteries,
>> unlike Ni-Cd and Ni-Mh cells. If you never discharge them below 80%,
>> and recharge them as soon as you can, they'll last for thousands of
>> charges. Deep discharging is so destructive, every battery has a
>> specially programmed IC in it to PREVENT you from discharging them below
>> 50%. That's when the IC tells the computer to shut down to protect the
>> battery pack from ultimate destruction.
>
>
> I thought the purpose of this mechanism was to prevent dataloss...
>

There is no such functionality or limitation. Larry made it all up.

>
>>
>> There is, and always has been, a problem with the IC and its
>> programming. What the IC THINKS is the current charge state of the pack
>> and what the REAL charge state of the pack is grow constantly wider
>> apart because the programming of the IC is an average for cells of this
>> type and the cells in your pack aren't average. So, every so often, I
>> like 2 months as a yardstick because my computer is discharged daily,
>> you need to "cycle" the battery pack to the point where the IC shuts
>> down the pack ("dead"), then IMMEDIATELY recharge the pack for a minimum
>> of 16 hours of continuous charging so the IC can find the point of full
>> charge, which it measures as a sudden rise of cell voltage under
>> charging current. A finishing charge, after the main high current
>> charge, is what takes so long and should not be disturbed. The IC will
>> shut down the charge, completely, to prevent overcharging which makes
>> these wonder batteries explode quite violently because cell warpage
>> results in internal shorting to hundreds of amps for a few
>> seconds..BOOM!
>
>
> Yes I've heard such stories, but never experienced an explosion myself
> yet. But I suppose it's always best NOT to leave any devices charging
> while leaving home. Exept perhaps if one has very good fire insurance.
>

There was some very good video on the Electronic Design magazine website for
a couple of years - sadly gone now. The batteries don't explode as such.
What happens is that they rupture under the excess pressure. Since the
electrolyte is a lithium salt disolved in a highly flammable organic solvent
and as the battery ruptures it is highly likely to generate a spark, the
electrolyte starts to burn fiercely. If there is no spark, the metallic
lithium displaced from the chemistry will spontaneously ignite and burn on
contact with air achieving the same result. As the battery is heated by the
fire, the chemistry generates oxygen in gaseous form which makes the burning
solvent burn even more fiercely. The result can be a torch like flame
ejecting from the battery for a distance of over one metre. Because the
battery provides its own fuel and oxygen, extinguishing a burning battery is
almost impossible.

This rather dramatic description only occurs if the battery is in any way
abused (overcharged, shorted or charged after an over discharge). As long
as it charged and used in accordance with the manufacturer's
recommendations, the technology is inherently safe as the monitoring
circuitry is designed to prevent abuse. I have to confess though, that I
try not to leave batteries on charge if I'm not at home.

>
>>
>> So, run it until it's dead every couple of months, then IMMEDIATELY
>> recharge for a minimum of 16 hours uninterrupted. All other times,
>
>
> That's the way I used it in the beginning (as also indicated in the
> manual). Though I want to point out that it certainly doesn't take 16
> hours before fully charges again! I estimate this takes about 3 hours at
> the most.
>

About right. You cannot charge it for 16 hours.

In news:4ab7d39f$0$83238$e4fe514c@news.xs4all.nl,
Linea Recta typed on Mon, 21 Sep 2009 21:26:41 +0200:
> "Linea Recta" <mccm.vos@abc.invalid> schreef in bericht
> news:4ab7cc59$0$83250$e4fe514c@news.xs4all.nl...
>>
>> "BillW50" <BillW50@aol.kom> schreef in bericht
>> news:h95to0$sc0$1@news.eternal-september.org...
>>> In news:4ab6745e$0$83248$e4fe514c@news.xs4all.nl,
>>> Linea Recta typed on Sun, 20 Sep 2009 20:27:39 +0200:
>>>> "BillW50" <BillW50@aol.kom> schreef in bericht
>>>> news:h95ed7$es$1@news.eternal-september.org...
>>>>> In news:4ab6318a$0$83248$e4fe514c@news.xs4all.nl,
>>>>> Linea Recta typed on Sun, 20 Sep 2009 15:43:35 +0200:
>>>>>> In the past I have replaced the CMOS power cell of my PC, but I
>>>>>> was wondering how is this done in a laptop? Is the cell
>>>>>> accessible at all?
>>>>>
>>>>> Most laptops and netbooks use Ni-HM batteries for the CMOS/RTC
>>>>> which the computer routinely recharges.
>>>>
>>>> Formerly I thought CMOS batteries op PC were recharged, but then I
>>>> learned, for some reason, this is not the case. So what's the logic
>>>> to do so only for laptops?
>>>
>>> I am not sure. As desktops could be designed with a rechargeable and
>>> laptops with a disposable. But it isn't generally the case. Maybe
>>> because most people can take a desktop apart while most can't
>>> handle a laptop disassembly I guess.
>>>
>>>>> They rarely fail so I wouldn't worry too
>>>>> much about them. I would worry more about the florescent lamp,
>>>>> inverter, hard drive, and main battery myself. Although if you are
>>>>> still interested, it usually requires total disassembly to get to
>>>>> it.
>>>>
>>>> I've already taken out the main battery to increase its lifespan.
>>>
>>> That is a very good idea. Some claim you should use them every 2
>>> months
>>
>>
>> That's about the scheme I follow.
>>
>>
>>> or so to keep the capacity up. Although I haven't really seen any
>>> evidence this is necessary. M.I.5¾ claims this by the way.
>>>
>>> Do you also monitor the CPU and drive temps? The CPU temp monitoring
>>> will let you know when it is time to do some dust bunny cleaning.
>>> <vbg>
>>
>>
>> Yes, and I noticed that the graphics temperature is rather high (62
>> Celcius)
>
>
> Update: 72 degrees Celcius half an hour after switching on...

Some laptops are easy to clean and some have to be completely
disassembled. My Gateway MX6124 laptops for example, have a trap door
and you can easily remove the fan and the whole heat exchanger for easy
cleaning or replacement.

--
Bill
Asus EEE PC 702G8 ~ 2GB RAM ~ 16GB-SDHC
Windows XP SP2

In news:4ab754c4$1_1@glkas0286.greenlnk.net,
M.I.5¾ typed on Mon, 21 Sep 2009 11:26:32 +0100:
> ... the battery is floated across a constant voltage source of 4.2
> volts per cell. Once the cell voltage rises to match the 4.2 volts the
> charge current stops (apart from an extremely small trickle that
> offsets self discharge). This occurs within about an hour of the end
> of main charge.

Keeping Li-Ion batteries floated to 4.2v per cell doesn't seem to last
for too many years in my experience. They seem to die 3 years or less.
Floated to 4.10v though 24/7, they seem to last forever. Pushing 6 years
plus now under my experiments.

Why does laptop manufactures use 4.2v instead of 4.1v per cell? Simple,
they can brag of higher capacity for one (you get a few extra minutes
out of it). And two, you will need another battery in a few years and
they hope they can sell you a new one.

> ... Deep discharging to 0% (i.e. 2.8 volts per cell does no harm
> or damage whatsoever).

Short-term wise anyway. My experiments tend to show batteries that never
drop lower than 50% capacity seems to last longer overall. But it is too
early in the study to say for sure.

> There is nothing in that paragraph that equates to reality. Li-ion
> batteries have to lowest self discharge rate of any rechargeable
> battery (apart from one relatively new Sony design). Li-ion
> batteries will have almost their full capacity after doing nothing
> for 3 months (or even more) after they are charged. However, the
> battery monitor circuit does take some current in some battery
> designs. Battery monitors do not contain any timer, they merely
> monitor voltage and current.

I wish this were true for John Doue and his Twinhead A9110 Li-Ion
batteries. As his batteries self discharge in a two week period of time.
My 18 lithiums haven't had this problem though.

> ... and I work in the Aerospace industry where we use a lot of
> batteries of many chemistries. There is currently no li-ion
> technology that will last for 1300 full charge and discharge cycles.

The smartest people I have found who really knows about lithium
batteries are those in the hobby of radio control (RC) electric
aircraft. No they are not generally very book smart or use fancy
terminology. Nor do they sport the fanciest electronic equipment. But
they do push their lithiums to extreme limits! As some of them draw over
100 amps from their batteries. And they learn very quickly the dos and
don'ts with lithiums. And they generally run without any safety circuits
as well.

And one thing becomes very clear and very important and also applies for
laptop users too. And that is *never* recharge a lithium right after
use. Let it cool down 20 minutes or more first. If you ignore this
warning, the capacity and the number of available recharges will drop
off very quickly. In the extreme RC field, I have seen lithiums become
useless in a mere couple of recharges if this rule is ignored.

> The one unfortunate aspect of the technology is that it does have the
> lowest charge/discharge capability of any recognised rechargeable
> chemistry (typically 300-500 full cycles)

Don't forget the very unpopular rechargeable alkaline. They are supposed
to get up to 25 recharges. Although I only get about 4 or 5 recharges
using a dedicated charger just made for them. Besides the capacity drops
off quickly after each recharge, they start to leak after 4 or 5
recharges. And it corrodes everything it touches. <sigh>

--
Bill
Asus EEE PC 702G8 ~ 2GB RAM ~ 16GB-SDHC
Windows XP SP2

"Linea Recta" <mccm.vos@abc.invalid> wrote in news:4ab7cfe8$0$83251
$e4fe514c@news.xs4all.nl:

> Thanks very much for the info.
>
>
>

I knew I'd be attacked, but you're quite welcome...(c;]



--
Larry

On Tue, 22 Sep 2009 07:49:24 +0100, "M.I.5¾" <no.one@no.where.NO_SPAM.co.uk>
wrote:

>
>"Larry" <noone@home.com> wrote in message
>news:Xns9C8D80BA0BA31noonehomecom@74.209.131.13.. .
>> "M.I.5¾" <no.one@no.where.NO_SPAM.co.uk> wrote in
>> news:4ab754c4$1_1@glkas0286.greenlnk.net:
>>
>>> Complete rubbish! It is the laptop internally generated heat that
>>> destroys the batteries when you leave them in.
>>>
>>
>> You must be using a MAC. REAL laptops have EXTERNAL and CHANGEABLE
>> batteries that are on the OUTSIDE of them....for a reason....
>>
>>
>
>How dare you.
>
>I wouldn't use that ****.
>

;O)
--
Gott läßt Israeliten 12000 Bewohner von Ai umbringen
(Das Buch Josua, Kap. 8) *** http://www.reimbibel.de ***
"Lock deren Heer aus ihrer Stadt * Den Raub, das Vieh dürft ihr euch teilen,
und mach dann ganz Ai platt. * lass nun dein Heer nach Ai eilen."

In news:4ab74dcf$1_1@glkas0286.greenlnk.net,
M.I.5¾ typed onMon, 21 Sep 2009 10:56:50 +0100 :
> "BillW50" <BillW50@aol.kom> wrote in message
> news:h95ed7$es$1@news.eternal-september.org...
>> In news:4ab6318a$0$83248$e4fe514c@news.xs4all.nl,
>> Linea Recta typed on Sun, 20 Sep 2009 15:43:35 +0200:
>>> In the past I have replaced the CMOS power cell of my PC, but I was
>>> wondering how is this done in a laptop? Is the cell accessible at
>>> all?
>>
>> Most laptops and netbooks use Ni-HM batteries for the CMOS/RTC which
>> the computer routinely recharges. They rarely fail so I wouldn't
>> worry too much about them. I would worry more about the florescent
>> lamp, inverter, hard drive, and main battery myself. Although if you
>> are still interested, it usually requires total disassembly to get
>> to it.
>
> While some use Ni-MH, they are nowhere near universal. Around 50% or
> so still use a lithium coin battery.

I haven't seen 50% using lithium coil cell at all. In fact, I never seen
any but just heard that a few do exists. They have been Ni-Cads or
Ni-MH.

> Ni-MH batteries do routinely
> fail as the succumb to Nickel whisker growth.

Are you sure you are not thinking of Ni-Cads? As those, I used to zap
them with a 12v car battery to fry the whiskers in two. Although even
this they were short lived. As once the whiskers start, it is like
cancer. Those cells their days were numbered. Supposedly Ni-Cads can
only work chemically for about 7 years and then they were done. I
personally have gotten far longer out of some of them. 5% to 10% of them
I have had them still going after 35 years. Although the capacity is
only like 5% of what they were originally.

Ni-MH I never had a whisker problem. In fact, I never had a Ni-MH go bad
on me yet. Only two bad things I know about them.

1) They can't take vibrations too well. So I am told from the RC camp
anyway. I never had a problem myself.

2) They like lithium gets very hot if you over charge them. Although I
never heard of them exploding or anything. They just gets hot enough to
cause something to catch on fire. Of course, when they have been heated
in this way, they don't last too long anymore. Well I should say their
capacity drops down very quickly. As they continue to work for many
years, but at a lower capacity.

--
Bill
Asus EEE PC 702G8 ~ 2GB RAM ~ 16GB-SDHC
Windows XP SP2

"BillW50" <BillW50@aol.kom> wrote in message
news:h9ahib$qlu$1@news.eternal-september.org...
> In news:4ab754c4$1_1@glkas0286.greenlnk.net,
> M.I.5¾ typed on Mon, 21 Sep 2009 11:26:32 +0100:
>> ... the battery is floated across a constant voltage source of 4.2 volts
>> per cell. Once the cell voltage rises to match the 4.2 volts the charge
>> current stops (apart from an extremely small trickle that offsets self
>> discharge). This occurs within about an hour of the end of main charge.
>
> Keeping Li-Ion batteries floated to 4.2v per cell doesn't seem to last for
> too many years in my experience. They seem to die 3 years or less. Floated
> to 4.10v though 24/7, they seem to last forever. Pushing 6 years plus now
> under my experiments.
>
> Why does laptop manufactures use 4.2v instead of 4.1v per cell? Simple,
> they can brag of higher capacity for one (you get a few extra minutes out
> of it). And two, you will need another battery in a few years and they
> hope they can sell you a new one.
>

As I have stated before, charging to 4.1 volts undercharges the battery by
over 30%. I have no experience of batteries floated on 4.2 volts dying
prematurely unless the charger is providing more than 4.2 volts. Just half
a percent high is enough to kill a battery in short order (but not enough to
cause rupture)

>> ... Deep discharging to 0% (i.e. 2.8 volts per cell does no harm
>> or damage whatsoever).
>
> Short-term wise anyway. My experiments tend to show batteries that never
> drop lower than 50% capacity seems to last longer overall. But it is too
> early in the study to say for sure.
>

I have no experience of premature life loss of any battery discharged to 2.8
volts. However, exceeding the maximum discharge current is almost
guaranteed to shorten the life of any battery. The maximum discharge
current of most designs is lower than you may think and for some designs is
as low as 0.3C.

>> There is nothing in that paragraph that equates to reality. Li-ion
>> batteries have to lowest self discharge rate of any rechargeable
>> battery (apart from one relatively new Sony design). Li-ion
>> batteries will have almost their full capacity after doing nothing
>> for 3 months (or even more) after they are charged. However, the
>> battery monitor circuit does take some current in some battery
>> designs. Battery monitors do not contain any timer, they merely
>> monitor voltage and current.
>
> I wish this were true for John Doue and his Twinhead A9110 Li-Ion
> batteries. As his batteries self discharge in a two week period of time.
> My 18 lithiums haven't had this problem though.
>

One Sony design has a very high self discharge rate, but it isn't that high.

>> ... and I work in the Aerospace industry where we use a lot of batteries
>> of many chemistries. There is currently no li-ion technology that will
>> last for 1300 full charge and discharge cycles.
>
> The smartest people I have found who really knows about lithium batteries
> are those in the hobby of radio control (RC) electric aircraft. No they
> are not generally very book smart or use fancy terminology. Nor do they
> sport the fanciest electronic equipment. But they do push their lithiums
> to extreme limits! As some of them draw over 100 amps from their
> batteries. And they learn very quickly the dos and don'ts with lithiums.
> And they generally run without any safety circuits as well.
>

That is very true, but modellers do buy lithium batteries that are
specifically designed for that sort of use. Batteries are available that
will tolerate 500-600 Amps of discharge, but they cost an arm and couple of
legs. There is a new design of battery from the US that has a relatively
huge capacity for its size. If they refine the design to the point where a
reasonable current can be drawn from it, they may have a winner - but it's
early days yet. We were loaned a sample about a year ago but there wasn't
much we could do with it.

> And one thing becomes very clear and very important and also applies for
> laptop users too. And that is *never* recharge a lithium right after use.
> Let it cool down 20 minutes or more first. If you ignore this warning, the
> capacity and the number of available recharges will drop off very quickly.
> In the extreme RC field, I have seen lithiums become useless in a mere
> couple of recharges if this rule is ignored.
>

In normal use, if the battery is warm, it isn't from internally generated
heat. As the lithium chemistry is 99% efficient, it generates practically
no heat of its own unless you are talking about the high discharge variety
where the battery does not get the opportunity to disipate what heat is
generated. The heat from the laptop itself warming the battery is another
issue however, but not all laptops do this.

>> The one unfortunate aspect of the technology is that it does have the
>> lowest charge/discharge capability of any recognised rechargeable
>> chemistry (typically 300-500 full cycles)
>
> Don't forget the very unpopular rechargeable alkaline. They are supposed
> to get up to 25 recharges. Although I only get about 4 or 5 recharges
> using a dedicated charger just made for them. Besides the capacity drops
> off quickly after each recharge, they start to leak after 4 or 5
> recharges. And it corrodes everything it touches. <sigh>
>

I would rather forget it if it's all the same to you.