Archived from groups: comp.sys.laptops (More info?)

Hi People,

I am looking to buy a laptop but I really hate the fact we are in the 21st
century and laptop batteries last for about a max of three hours and have a
lifespan of 3 years. I would like to know what people think about 'tweaking'
your laptop to extend its operating time and its lifespan. I have listed
below a few points below that I heard would help optimise the battery's
performance.

- Disable background programs which use up power from the CPU and hard
drive.
- Disable network connections unless it's in use.
- Choose a laptop which uses a Centrino/Pentium M processor which alters
processor speed rather than a standard P4
- Reduce the brightness of the display. Turn off when not in use.
- Add more RAM so it reduces the usage of hard drive.

Am I right in thinking this will help prolong its duration? Does anyone have
any other pointers?

Also, can a someone confirm whether the statements below are true please:
"it's best to store batteries at about 40% charge"
"Never store them for long periods completely discharged or they might not
recharge at all"
"It's better not to fully discharge lithium-ion batteries " - note: I heard
you should Fully drain and fully recharged your battery pack every few
months.

Thanks in advance,
Nick.

Archived from groups: comp.sys.laptops (More info?)

While each of those things listed may reduce power requirements, I doubt
that the difference would be measurable and noticeable.
"Ellada" <ellada@blueyonder.co.uk> wrote in message
news:uIcHe.69665$Pf3.21921@fe2.news.blueyonder.co.uk...
> Hi People,
>
> I am looking to buy a laptop but I really hate the fact we are in the 21st
> century and laptop batteries last for about a max of three hours and have
> a
> lifespan of 3 years. I would like to know what people think about
> 'tweaking'
> your laptop to extend its operating time and its lifespan. I have listed
> below a few points below that I heard would help optimise the battery's
> performance.
>
> - Disable background programs which use up power from the CPU and hard
> drive.
> - Disable network connections unless it's in use.
> - Choose a laptop which uses a Centrino/Pentium M processor which alters
> processor speed rather than a standard P4
> - Reduce the brightness of the display. Turn off when not in use.
> - Add more RAM so it reduces the usage of hard drive.
>
> Am I right in thinking this will help prolong its duration? Does anyone
> have
> any other pointers?
>
> Also, can a someone confirm whether the statements below are true please:
> "it's best to store batteries at about 40% charge"
> "Never store them for long periods completely discharged or they might not
> recharge at all"
> "It's better not to fully discharge lithium-ion batteries " - note: I
> heard
> you should Fully drain and fully recharged your battery pack every few
> months.
>
> Thanks in advance,
> Nick.
>
>
>

Archived from groups: comp.sys.laptops (More info?)

All of your steps put together will make very little difference (not
zero, perhaps, but very little).

Part of your assumption is wrong, Lithium batteries can last a decade if
properly cared for and not cycled too often (calendar time aside, they
are good for 200 to 500 "use and recharge" cycles). From what I've
seen, the primary definition of "proper care" is removing the batteries
when the laptop will be run on AC power for long periods of time (days).
The culprits are both overcharging (only in some laptops and with some
batteries, but it clearly happens in some models) and heat, but leaving
a battery in a laptop that is constantly running on AC usually destroys
the battery in 9 to 24 months, while lithium batteries that are removed
from their laptops often last 5 years to nearly or more than a decade.

The usual recommendation for lithium batteries is to store them at 40%
to 60% charge, but I usually store mine at full charge and I have over a
dozen Toshiba lithium batteries made in 1996 to 1998 that are still
capable of running a laptop for more than 2 hours.

The "full drain and recharge" advice is right for NiCad batteries but
DEAD WRONG for lithium batteries. In fact, it's best not to discharge
lithium batteries below about 20% to 25%.

Understand that there are 3 types of batteries that have been used in
laptops, NiCad, NiMH and Lithium. NiCads are no longer used at all as
far as I know, and NiMH is only rarely used in low-cost laptops.
Lithiums are by far the best. However, some of the "care" rules are
specific to each of these 3 types of batteries. All of my comments
presume lithium.


Ellada wrote:

> Hi People,
>
> I am looking to buy a laptop but I really hate the fact we are in the 21st
> century and laptop batteries last for about a max of three hours and have a
> lifespan of 3 years. I would like to know what people think about 'tweaking'
> your laptop to extend its operating time and its lifespan. I have listed
> below a few points below that I heard would help optimise the battery's
> performance.
>
> - Disable background programs which use up power from the CPU and hard
> drive.
> - Disable network connections unless it's in use.
> - Choose a laptop which uses a Centrino/Pentium M processor which alters
> processor speed rather than a standard P4
> - Reduce the brightness of the display. Turn off when not in use.
> - Add more RAM so it reduces the usage of hard drive.
>
> Am I right in thinking this will help prolong its duration? Does anyone have
> any other pointers?
>
> Also, can a someone confirm whether the statements below are true please:
> "it's best to store batteries at about 40% charge"
> "Never store them for long periods completely discharged or they might not
> recharge at all"
> "It's better not to fully discharge lithium-ion batteries " - note: I heard
> you should Fully drain and fully recharged your battery pack every few
> months.
>
> Thanks in advance,
> Nick.
>
>
>

Archived from groups: comp.sys.laptops (More info?)

Barry Watzman wrote:
> All of your steps put together will make very little difference (not
> zero, perhaps, but very little).
>
> Part of your assumption is wrong, Lithium batteries can last a decade if
> properly cared for and not cycled too often (calendar time aside, they
> are good for 200 to 500 "use and recharge" cycles). From what I've
> seen, the primary definition of "proper care" is removing the batteries
> when the laptop will be run on AC power for long periods of time (days).
> The culprits are both overcharging (only in some laptops and with some
> batteries, but it clearly happens in some models) and heat, but leaving
> a battery in a laptop that is constantly running on AC usually destroys
> the battery in 9 to 24 months, while lithium batteries that are removed
> from their laptops often last 5 years to nearly or more than a decade.
>
> The usual recommendation for lithium batteries is to store them at 40%
> to 60% charge, but I usually store mine at full charge and I have over a
> dozen Toshiba lithium batteries made in 1996 to 1998 that are still
> capable of running a laptop for more than 2 hours.
>
> The "full drain and recharge" advice is right for NiCad batteries but
> DEAD WRONG for lithium batteries. In fact, it's best not to discharge
> lithium batteries below about 20% to 25%.
>
> Understand that there are 3 types of batteries that have been used in
> laptops, NiCad, NiMH and Lithium. NiCads are no longer used at all as
> far as I know, and NiMH is only rarely used in low-cost laptops.
> Lithiums are by far the best. However, some of the "care" rules are
> specific to each of these 3 types of batteries. All of my comments
> presume lithium.
>

That said, how long can the batteries be left out of the laptop before
needing to be topped off?

Archived from groups: comp.sys.laptops (More info?)

http://www.batteryuniversity.com/index.htm

Has anyone ever referred to the above site for battery info on charging,
storage, use etc? The site is sponsored by Cadex but the info seems
genuine. Some of these ongoing battery questions and discussions might find
resolution here :-)


"William Andersen" <wgander@cox.net> wrote in message

> "Ellada" <ellada@blueyonder.co.uk> wrote in message

Archived from groups: comp.sys.laptops (More info?)

Thank you everyone for your advise. The laptop I will buy has a Lithium
battery. I have learnt the following are more efficient methods to prolong
battery duration:
-I will try and power my laptop the majority of the time by AC connection
(with the battery removed obviously). I will store my battery at above 50%
when not in use.
-I will not discharge my battery below 20%.
-I will not overcharge my battery
-I will avoid using the battery in intense heat

BTW, Can it harm a laptop to never use a battery and use it as a desktop PC
with an AC connection?

Thanks again,
Nick.


"Ellada" <ellada@blueyonder.co.uk> wrote in message
news:uIcHe.69665$Pf3.21921@fe2.news.blueyonder.co.uk...
> Hi People,
>
> I am looking to buy a laptop but I really hate the fact we are in the 21st
> century and laptop batteries last for about a max of three hours and have
a
> lifespan of 3 years. I would like to know what people think about
'tweaking'
> your laptop to extend its operating time and its lifespan. I have listed
> below a few points below that I heard would help optimise the battery's
> performance.
>
> - Disable background programs which use up power from the CPU and hard
> drive.
> - Disable network connections unless it's in use.
> - Choose a laptop which uses a Centrino/Pentium M processor which alters
> processor speed rather than a standard P4
> - Reduce the brightness of the display. Turn off when not in use.
> - Add more RAM so it reduces the usage of hard drive.
>
> Am I right in thinking this will help prolong its duration? Does anyone
have
> any other pointers?
>
> Also, can a someone confirm whether the statements below are true please:
> "it's best to store batteries at about 40% charge"
> "Never store them for long periods completely discharged or they might not
> recharge at all"
> "It's better not to fully discharge lithium-ion batteries " - note: I
heard
> you should Fully drain and fully recharged your battery pack every few
> months.
>
> Thanks in advance,
> Nick.
>
>
>

Archived from groups: comp.sys.laptops (More info?)

There's no fixed answer to your question ("how long can the batteries be
left out of the laptop before needing to be topped off?" ), but
definitely years, I have batteries that have been treated that way and
that are still good. In fact, I have batteries that have been left IN
a laptop for 2 years that are still good after recharging, and that's
clearly worse since there is always some current drain even when the
laptop is off.


Jim wrote:
> Barry Watzman wrote:
>
>> All of your steps put together will make very little difference (not
>> zero, perhaps, but very little).
>>
>> Part of your assumption is wrong, Lithium batteries can last a decade
>> if properly cared for and not cycled too often (calendar time aside,
>> they are good for 200 to 500 "use and recharge" cycles). From what
>> I've seen, the primary definition of "proper care" is removing the
>> batteries when the laptop will be run on AC power for long periods of
>> time (days). The culprits are both overcharging (only in some laptops
>> and with some batteries, but it clearly happens in some models) and
>> heat, but leaving a battery in a laptop that is constantly running on
>> AC usually destroys the battery in 9 to 24 months, while lithium
>> batteries that are removed from their laptops often last 5 years to
>> nearly or more than a decade.
>>
>> The usual recommendation for lithium batteries is to store them at 40%
>> to 60% charge, but I usually store mine at full charge and I have over
>> a dozen Toshiba lithium batteries made in 1996 to 1998 that are still
>> capable of running a laptop for more than 2 hours.
>>
>> The "full drain and recharge" advice is right for NiCad batteries but
>> DEAD WRONG for lithium batteries. In fact, it's best not to discharge
>> lithium batteries below about 20% to 25%.
>>
>> Understand that there are 3 types of batteries that have been used in
>> laptops, NiCad, NiMH and Lithium. NiCads are no longer used at all as
>> far as I know, and NiMH is only rarely used in low-cost laptops.
>> Lithiums are by far the best. However, some of the "care" rules are
>> specific to each of these 3 types of batteries. All of my comments
>> presume lithium.
>>
>
> That said, how long can the batteries be left out of the laptop before
> needing to be topped off?

Archived from groups: comp.sys.laptops (More info?)

Using the laptop only with AC is generally fine, but you may want to get
a UPS (some people think that this is silly, but a new OEM lithium
battery costs $200+, and a laptop is 80% to 90% less expensive). In
fact, this week, some of the major electronics chains have the APC 350va
ups on sale for $19.95 after rebates. The considerations and arguments
for getting one vs. not getting one are the same as for a desktop PC.
Personally, I have come to the position of recommending that ALL PCs be
powered from a UPS. For a laptop, the battery certainly is a UPS, it's
just a very expensive $200+ UPS when a $20 UPS would work as well
(better in fact, as the run time is a lot longer if nothing else is
plugged into the UPS).


Ellada wrote:

> Thank you everyone for your advise. The laptop I will buy has a Lithium
> battery. I have learnt the following are more efficient methods to prolong
> battery duration:
> -I will try and power my laptop the majority of the time by AC connection
> (with the battery removed obviously). I will store my battery at above 50%
> when not in use.
> -I will not discharge my battery below 20%.
> -I will not overcharge my battery
> -I will avoid using the battery in intense heat
>
> BTW, Can it harm a laptop to never use a battery and use it as a desktop PC
> with an AC connection?
>
> Thanks again,
> Nick.
>
>
> "Ellada" <ellada@blueyonder.co.uk> wrote in message
> news:uIcHe.69665$Pf3.21921@fe2.news.blueyonder.co.uk...
>
>>Hi People,
>>
>>I am looking to buy a laptop but I really hate the fact we are in the 21st
>>century and laptop batteries last for about a max of three hours and have
>
> a
>
>>lifespan of 3 years. I would like to know what people think about
>
> 'tweaking'
>
>>your laptop to extend its operating time and its lifespan. I have listed
>>below a few points below that I heard would help optimise the battery's
>>performance.
>>
>>- Disable background programs which use up power from the CPU and hard
>>drive.
>>- Disable network connections unless it's in use.
>>- Choose a laptop which uses a Centrino/Pentium M processor which alters
>>processor speed rather than a standard P4
>>- Reduce the brightness of the display. Turn off when not in use.
>>- Add more RAM so it reduces the usage of hard drive.
>>
>>Am I right in thinking this will help prolong its duration? Does anyone
>
> have
>
>>any other pointers?
>>
>>Also, can a someone confirm whether the statements below are true please:
>>"it's best to store batteries at about 40% charge"
>>"Never store them for long periods completely discharged or they might not
>>recharge at all"
>>"It's better not to fully discharge lithium-ion batteries " - note: I
>
> heard
>
>>you should Fully drain and fully recharged your battery pack every few
>>months.
>>
>>Thanks in advance,
>>Nick.
>>
>>
>>
>
>
>

Archived from groups: comp.sys.laptops (More info?)

Make that "a UPS is 80% to 90% less expensive".


Barry Watzman wrote:

> Using the laptop only with AC is generally fine, but you may want to get
> a UPS (some people think that this is silly, but a new OEM lithium
> battery costs $200+, and a laptop is 80% to 90% less expensive). In
> fact, this week, some of the major electronics chains have the APC 350va
> ups on sale for $19.95 after rebates. The considerations and arguments
> for getting one vs. not getting one are the same as for a desktop PC.
> Personally, I have come to the position of recommending that ALL PCs be
> powered from a UPS. For a laptop, the battery certainly is a UPS, it's
> just a very expensive $200+ UPS when a $20 UPS would work as well
> (better in fact, as the run time is a lot longer if nothing else is
> plugged into the UPS).
>
>
> Ellada wrote:
>
>> Thank you everyone for your advise. The laptop I will buy has a Lithium
>> battery. I have learnt the following are more efficient methods to
>> prolong
>> battery duration:
>> -I will try and power my laptop the majority of the time by AC connection
>> (with the battery removed obviously). I will store my battery at above
>> 50%
>> when not in use.
>> -I will not discharge my battery below 20%.
>> -I will not overcharge my battery
>> -I will avoid using the battery in intense heat
>>
>> BTW, Can it harm a laptop to never use a battery and use it as a
>> desktop PC
>> with an AC connection?
>>
>> Thanks again,
>> Nick.
>>
>>
>> "Ellada" <ellada@blueyonder.co.uk> wrote in message
>> news:uIcHe.69665$Pf3.21921@fe2.news.blueyonder.co.uk...
>>
>>> Hi People,
>>>
>>> I am looking to buy a laptop but I really hate the fact we are in the
>>> 21st
>>> century and laptop batteries last for about a max of three hours and
>>> have
>>
>>
>> a
>>
>>> lifespan of 3 years. I would like to know what people think about
>>
>>
>> 'tweaking'
>>
>>> your laptop to extend its operating time and its lifespan. I have listed
>>> below a few points below that I heard would help optimise the battery's
>>> performance.
>>>
>>> - Disable background programs which use up power from the CPU and hard
>>> drive.
>>> - Disable network connections unless it's in use.
>>> - Choose a laptop which uses a Centrino/Pentium M processor which alters
>>> processor speed rather than a standard P4
>>> - Reduce the brightness of the display. Turn off when not in use.
>>> - Add more RAM so it reduces the usage of hard drive.
>>>
>>> Am I right in thinking this will help prolong its duration? Does anyone
>>
>>
>> have
>>
>>> any other pointers?
>>>
>>> Also, can a someone confirm whether the statements below are true
>>> please:
>>> "it's best to store batteries at about 40% charge"
>>> "Never store them for long periods completely discharged or they
>>> might not
>>> recharge at all"
>>> "It's better not to fully discharge lithium-ion batteries " - note: I
>>
>>
>> heard
>>
>>> you should Fully drain and fully recharged your battery pack every few
>>> months.
>>>
>>> Thanks in advance,
>>> Nick.
>>>
>>>
>>>
>>
>>
>>

Archived from groups: comp.sys.laptops (More info?)

"Ellada" <ellada@blueyonder.co.uk> wrote in message
news:T4qHe.3871$GO1.3020@fe3.news.blueyonder.co.uk...
> Thank you everyone for your advise. The laptop I will buy has a Lithium
> battery. I have learnt the following are more efficient methods to prolong
> battery duration:
> -I will try and power my laptop the majority of the time by AC connection
> (with the battery removed obviously). I will store my battery at above 50%
> when not in use.
> -I will not discharge my battery below 20%.
> -I will not overcharge my battery
> -I will avoid using the battery in intense heat
>

You will need to ocassionally put the battery in and allow the laptop to
discharge it until it cuts off. This is necessary to calibrate the battery
state of charge circuitry. Recharge the battery immediately. For the use
you indicate, once a year should be fine.

FWIW: my laptop battery is nearly 3 years old and still delivers practically
a full charge. I have Li-ion batteries in a MiniDisc walkman that are 11
years old and give full charge. And I have 2 camcorder batteries that
clapped out after a year (but as they are Sony, this is to be expected).

Ian.

Archived from groups: comp.sys.laptops (More info?)

Thanks to everyone, and especially to Barry, for their advice.

I will be mainly using AC connection to power my laptop and occasionally by
a battery pack. I will be purchasing a UPS to prevent any power cuts
effecting the laptop. I'm now thinking that it's not really as complex as I
initially thought.

Any more tips would be appreciated but I think I have the idea.

Cheers.

Nick.

"Barry Watzman" <WatzmanNOSPAM@neo.rr.com> wrote in message
news:42EE4577.4050707@neo.rr.com...
> Make that "a UPS is 80% to 90% less expensive".
>
>
> Barry Watzman wrote:
>
> > Using the laptop only with AC is generally fine, but you may want to get
> > a UPS (some people think that this is silly, but a new OEM lithium
> > battery costs $200+, and a laptop is 80% to 90% less expensive). In
> > fact, this week, some of the major electronics chains have the APC 350va
> > ups on sale for $19.95 after rebates. The considerations and arguments
> > for getting one vs. not getting one are the same as for a desktop PC.
> > Personally, I have come to the position of recommending that ALL PCs be
> > powered from a UPS. For a laptop, the battery certainly is a UPS, it's
> > just a very expensive $200+ UPS when a $20 UPS would work as well
> > (better in fact, as the run time is a lot longer if nothing else is
> > plugged into the UPS).
> >
> >
> > Ellada wrote:
> >
> >> Thank you everyone for your advise. The laptop I will buy has a Lithium
> >> battery. I have learnt the following are more efficient methods to
> >> prolong
> >> battery duration:
> >> -I will try and power my laptop the majority of the time by AC
connection
> >> (with the battery removed obviously). I will store my battery at above
> >> 50%
> >> when not in use.
> >> -I will not discharge my battery below 20%.
> >> -I will not overcharge my battery
> >> -I will avoid using the battery in intense heat
> >>
> >> BTW, Can it harm a laptop to never use a battery and use it as a
> >> desktop PC
> >> with an AC connection?
> >>
> >> Thanks again,
> >> Nick.
> >>
> >>
> >> "Ellada" <ellada@blueyonder.co.uk> wrote in message
> >> news:uIcHe.69665$Pf3.21921@fe2.news.blueyonder.co.uk...
> >>
> >>> Hi People,
> >>>
> >>> I am looking to buy a laptop but I really hate the fact we are in the
> >>> 21st
> >>> century and laptop batteries last for about a max of three hours and
> >>> have
> >>
> >>
> >> a
> >>
> >>> lifespan of 3 years. I would like to know what people think about
> >>
> >>
> >> 'tweaking'
> >>
> >>> your laptop to extend its operating time and its lifespan. I have
listed
> >>> below a few points below that I heard would help optimise the
battery's
> >>> performance.
> >>>
> >>> - Disable background programs which use up power from the CPU and hard
> >>> drive.
> >>> - Disable network connections unless it's in use.
> >>> - Choose a laptop which uses a Centrino/Pentium M processor which
alters
> >>> processor speed rather than a standard P4
> >>> - Reduce the brightness of the display. Turn off when not in use.
> >>> - Add more RAM so it reduces the usage of hard drive.
> >>>
> >>> Am I right in thinking this will help prolong its duration? Does
anyone
> >>
> >>
> >> have
> >>
> >>> any other pointers?
> >>>
> >>> Also, can a someone confirm whether the statements below are true
> >>> please:
> >>> "it's best to store batteries at about 40% charge"
> >>> "Never store them for long periods completely discharged or they
> >>> might not
> >>> recharge at all"
> >>> "It's better not to fully discharge lithium-ion batteries " - note: I
> >>
> >>
> >> heard
> >>
> >>> you should Fully drain and fully recharged your battery pack every few
> >>> months.
> >>>
> >>> Thanks in advance,
> >>> Nick.
> >>>
> >>>
> >>>
> >>
> >>
> >>

Archived from groups: comp.sys.laptops (More info?)

Barry, is the below true?

"A laptop doesn't need UPS because its own battery will last 2-3 hours if
the
mains fails which is just as good as UPS. So just leave the battery in the
laptop. Don't even think of removing it for the first couple of years by
which time it might need replacing if it's had many discharge cycles, which
yours won't from the description of expected use

If you're not there for some reason and the battery goes flat when there is
a power cut, most laptops will go into standby mode and preserve the current
programs on the hard disk so when the mains comes back on it will restore to
its previous configuration."

Thanks in advance.

"Barry Watzman" <WatzmanNOSPAM@neo.rr.com> wrote in message
news:42EE44F6.4030609@neo.rr.com...
> Using the laptop only with AC is generally fine, but you may want to get
> a UPS (some people think that this is silly, but a new OEM lithium
> battery costs $200+, and a laptop is 80% to 90% less expensive). In
> fact, this week, some of the major electronics chains have the APC 350va
> ups on sale for $19.95 after rebates. The considerations and arguments
> for getting one vs. not getting one are the same as for a desktop PC.
> Personally, I have come to the position of recommending that ALL PCs be
> powered from a UPS. For a laptop, the battery certainly is a UPS, it's
> just a very expensive $200+ UPS when a $20 UPS would work as well
> (better in fact, as the run time is a lot longer if nothing else is
> plugged into the UPS).
>
>
> Ellada wrote:
>
> > Thank you everyone for your advise. The laptop I will buy has a Lithium
> > battery. I have learnt the following are more efficient methods to
prolong
> > battery duration:
> > -I will try and power my laptop the majority of the time by AC
connection
> > (with the battery removed obviously). I will store my battery at above
50%
> > when not in use.
> > -I will not discharge my battery below 20%.
> > -I will not overcharge my battery
> > -I will avoid using the battery in intense heat
> >
> > BTW, Can it harm a laptop to never use a battery and use it as a desktop
PC
> > with an AC connection?
> >
> > Thanks again,
> > Nick.
> >
> >
> > "Ellada" <ellada@blueyonder.co.uk> wrote in message
> > news:uIcHe.69665$Pf3.21921@fe2.news.blueyonder.co.uk...
> >
> >>Hi People,
> >>
> >>I am looking to buy a laptop but I really hate the fact we are in the
21st
> >>century and laptop batteries last for about a max of three hours and
have
> >
> > a
> >
> >>lifespan of 3 years. I would like to know what people think about
> >
> > 'tweaking'
> >
> >>your laptop to extend its operating time and its lifespan. I have listed
> >>below a few points below that I heard would help optimise the battery's
> >>performance.
> >>
> >>- Disable background programs which use up power from the CPU and hard
> >>drive.
> >>- Disable network connections unless it's in use.
> >>- Choose a laptop which uses a Centrino/Pentium M processor which alters
> >>processor speed rather than a standard P4
> >>- Reduce the brightness of the display. Turn off when not in use.
> >>- Add more RAM so it reduces the usage of hard drive.
> >>
> >>Am I right in thinking this will help prolong its duration? Does anyone
> >
> > have
> >
> >>any other pointers?
> >>
> >>Also, can a someone confirm whether the statements below are true
please:
> >>"it's best to store batteries at about 40% charge"
> >>"Never store them for long periods completely discharged or they might
not
> >>recharge at all"
> >>"It's better not to fully discharge lithium-ion batteries " - note: I
> >
> > heard
> >
> >>you should Fully drain and fully recharged your battery pack every few
> >>months.
> >>
> >>Thanks in advance,
> >>Nick.
> >>
> >>
> >>
> >
> >
> >

Archived from groups: comp.sys.laptops (More info?)

"Ellada" <ellada@blueyonder.co.uk> wrote in message
news:iESHe.3379$Rk2.2237@fe3.news.blueyonder.co.uk...
>
> "A laptop doesn't need UPS because its own battery will last 2-3 hours if
> the
> mains fails which is just as good as UPS. So just leave the battery in
the
> laptop. Don't even think of removing it for the first couple of years by
> which time it might need replacing if it's had many discharge cycles,
which
> yours won't from the description of expected use
>
> If you're not there for some reason and the battery goes flat when there
is
> a power cut, most laptops will go into standby mode and preserve the
current
> programs on the hard disk so when the mains comes back on it will restore
to
> its previous configuration."
>
> Thanks in advance.
>

Well what you say is technically correct. But, as has been said before, why
use a $100-200 battery to do the job of a $30 UPS? Annecdotal evidence
suggests that Li-ion batteries do have short lives when left in Laptops run
on AC even if they are not actually used. I personally believe this is more
of a heat problem than an overcharging issue. UPSs generally use
Lead-Calcium batteries which are designed to be kept on float charge (and
don't mind a bit of warmth either).

Ian.