There's a lot of information about that if you keep a Laptop battery
charged between only 80% full and only 40% full, it will be servicable
over the years for four times as long.
Other information I find says it is the charging and discharging that
wears the battery out.
The laptop i have (with a built in battery) is mainly used in one room,
so it is easy to keep it plugged in *all the time* to mains electricity.
Would it be better to prolong the life of the battery to keep it plugged
in all the time or to go for the 80% - 40% option. Thanks.
I asked a similar question a couple of years ago, in a computer
newsgroup, and there was little consensus about the best method of
conserving the battery. It will be interesting to see if there is
I bought this laptop new about four years ago, and used it with the
battery installed, but using the mains, and the battery power is almost
zero now, so I am looking for the best way to treat a replacement
There's several things that control the life of rechargeable batteries:
The quality of the cells
The temperature they run at (and available cooling)
The loads they get put to (see temperature)
The smartness of the battery manager in terms of charging, discharging and
As always 'it depends', but I'd suggest the battery manager is smarter than
you are are regards maintaining the optimal state of charge to keep the
battery happy. The only thing is that it has no prescience over what you're
going to do in future - eg store the laptop for months unplugged - but
otherwise I'd suggest it's best to leave it to it.
That doesn't apply so much to old laptops (dumb batteries), cheaper laptops
(poorly written management software) or removable batteries (in some cases
the manager might be in the appliance or charger not in the battery -
unlikely with laptops but can apply to eg power tools).
It'll depend on the battery manager in that particular machine, but one
thing to say is keep the battery cool. If the laptop gets hot, that'll
degrade battery life. Also it's worth using the battery from time to time -
don't leave it on charger forever. But otherwise it's going to be pretty
hard to maintain 40-80% without causing lots of charge/discharge cycles
which will wear the battery.
On Friday, 9 December 2016 11:23:48 UTC, john west wrote:
it probbably depends on teh tyep of battery and the make of teh battery and
charging circuit, I'm sure Apple used to advise discharging it comnpletely
every month adn then charging it to full as this updates the info of teh b
attery condition so it can fully charge rather than part charge.
well yes they have a 'life cycle' but I'm not sure with todays battereis wh
ether charging them up every hour to keep them charged is the best option
on to let them go below 10% is best.
Not havign a labtop means I don;lt have to think about it. I charge my iup
ad when I;m NOT using it and it;s below about 50% charged.
Last night it stopped while I was listening to a podcast 4% was the last I
noticed. So at 1:10am I decided I might as well go to bed and charge the ip
ad ready for the morning.
My wife's Samsung netbook has a setting for battery conservation which
is 80%. If we are travelling we reset this to 100% but at home it is
back to 80%. This is an early 2012 purchase and without specific
testing the battery appears fine.
For my main Lenovo laptop (2007) I have two batteries. The original
and now basically defunct battery is in all the time, it just about
has enough juice to shut down on no power. The other I only use if
I'm about to travel.
I've taken the battery out of an occasionally used laptop which
essentially makes it no different to a normal desktop computer as far
as power is concerned.
It depends on the charger in the laptop. I have an Acer laptop - not the
cheapest they did - which cooks the battery if left in the machine. So I
remove it when not needed. A better designed one wouldn't cause problems.
Dave Plowman email@example.com London SW
Yeah, I have a Compaq that I chose to leave permanently on charge 24/7/365
which saw the battery last for well over a decade now. The double capacity
has only just died and I have gone back to the original normal capacity
On Fri, 09 Dec 2016 13:19:36 +0000, Dave Plowman (News) wrote:
Such as the (11 year old) Acer Aspire 3660 I've had on permanent
'charge' for the whole of its life to date which seems to still have
around 70% or so of its original battery capacity.
I figure the battery has lasted this long because of the more
'sympathetic' charge maintenance routine which avoids the "Float
Charging" concept, electing instead to charge up to the 4.2v per cell
level and then leave the battery to slowly decline in voltage over the
several weeks of mains powered use before giving it a 10 or 15 minute
topping up charge.
As you can imagine, the chances of 'catching it in the act' of
'charging' on such a low duty cycle are almost zero but I did eventually
see the green battery light change to the red 'charging' state for a ten
or 15 minute period before turning green again after a few years of
ownership. Subsequent to which event, I then paid the battery charge
light a little more attention which allowed me to witness a few more of
these 'topping up' charge events over the next 5 or 6 years.
Sadly, this laptop has rather outlived its usefulness so it simply sits
perched on top of the filing cabinet where it has spent 99.99% of its 11
year life, plugged into the charger to maintain the battery whilst I
ponder its future (if any). :-(
The one on mine was knackered after not much more than a year. It's a
5536. Of course if you used the battery every day - perhaps what a laptop
is meant for - having it fully charged whenever possible might be
important. Only when I Googled did I find that the battery didn't like
being left in with the laptop PS left on 24/7. So I now remove the
replacment battery when not needed.
It's odd they changed the concept of battery charging.
My 5536 was also the one where the soldering to one of the processors
failed. Luckily, found a firm who fixed it for an affordable sum. And it
seems OK now - although I've now got a better one.
*A journey of a thousand sites begins with a single click *
Dave Plowman firstname.lastname@example.org London SW
On Sun, 11 Dec 2016 11:12:28 +0000, Dave Plowman (News) wrote:
I'm pretty certain I didn't spot the battery state led turning red ('out
of the blue' as it were) until after a few years of ownership. I was
already aware that the battery had, contrary to most laptop users'
experience, retained pretty well most of its original capacity. It was a
'half celled' battery pack so only offered an autonomy of 100 minutes or
so to begin with - not a problem since I wasn't anticipating any need to
use it untethered for any longer than half an hour or so any more
frequently than maybe 10 to 20 times a year.
Since that laptop was rarely disconnected from its charging brick, my
discovery of this 'topping up' charging state made me reconsider my
preconceived assumption that the battery was on a continual float
charging regime where the cells would be held at 4.2v all the time it was
connected to the charging brick.
Topping the battery up with a ten minute charge every few weeks rather
went against the notion of a constant 4.2v per cell float charging regime
and since the battery condition was so good after several years' worth of
'float charge abuse', I was forced to conclude that 'float charging' was
most definitely 'off the menu' in this case.
The big problem with that Acer Aspire 3660 is that the 32 bit Linux
distros don't play nicely with whatever gimmickry Acer have applied to
the Intel chipset they've used.
I can install and run Linux ok, along with Kaffeine, but instead of a
mere 20W idle under win2k (I ripped out that shite winXP MCE it had
originally been afflicted with within the first week of ownership), I was
seeing an idle consumption of 30W along with the need to manually
intervene on shutdown with the 4 second press and hold of the power
button after allowing sufficient time for Linux to flush cached data back
to the disk.
I'm now considering buying a refurbished dual HDD laptop with 1920 by
1080 HD screen sans the Microsoft tax from one of the more specialised
suppliers. I don't want to be stuck with a "Wintel" only laptop,
particularly when Microsoft have taken their ownership of *your* PC to
the even greater outrageous levels of windows 10 making the winXP 'piss
take' look like a harmless prank.
The modern day laptops currently available around the three to six
hundred quid mark (I paid a mere £399.97 at the Tesco Superstore for that
laptop 11 years ago) all have displays little better than the 15.4 Inch
1280 x 800 TFT Screen of that 11 year old laptop (typically with screen
resolutions of 1366 by 768 which, although sporting an extra 25Kpxel over
and above the 1024Kpxel of that ancient Acer, is actually an even less
useful display format - progress *not*!).
I was looking at upgrading to a better laptop about 3 months ago but
since I needed something guaranteed to work with a modern Linux distro,
the choice went beyond merely picking out the best bang for my buck model
from the likes of Argos and Tesco Superstore so the the upgrade 'project'
got shoved onto the back burner. It looks like I'll have to google for
the thread I started in the uk.comp.os.linux way back then to remind
myself of the excellent advice and several recommendations I received in
regard of trustworthy suppliers. :-)
If they actually made one as compact as a laptop with the same size
screen, yes. And one designed to be folded up flat and moved when not in
use. In the same way as you might use a laptop on the kitchen table, etc,
then move it when eating.
*I will always cherish the initial misconceptions I had about you
Dave Plowman email@example.com London SW
On Mon, 12 Dec 2016 03:41:07 -0800, whisky-dave wrote:
I'd bought it as a diagnostic aid for call out work, usually to sort out
network connectivity issues. Rather than let it languish unused in
between call outs, I decided it could act as a TV Recording Scheduling
conflict resolver by plugging a DVB-T usb stick into one of the usb ports
on the rear panel and running DTVR as my most basic of basic PVR software.
Running DVB-T recording software in a windows environment involved many
compromises and limits (such as the need for one tuner per scheduled
recording to resolve any scheduling conflicts and not being able to
specify a globally set in and out padding whenever there was a string of
back to back programmes to be recorded from a particular "TV channel").
The work-around in this case being to treat the whole period as one huge
programme to be split into its seperate programmes *after* the whole
recording had finally completed, sometimes a whole 5 to 7 hours later!
The point being that the laptop can (and did!) manage battery care
rather better than I ever could. :-)
Unlike EoLed laptops, they do at least retain their one and only
function (assuming they've been stored in a dry location) so may
eventually prove their worth perhaps even decades later. If you have a
big enough collection you can simply 'flat pack' them and tuck them away
somewhere dry and out of sight. :-)
Both are true, but keeping it fully charged all the time kills it even
faster than cycling it through periodic discharge. It is bad to keep it
near either end of the spectrum for long periods of time. How hot the PC
gets plays a part too - and they generally run faster and hotter on
mains when all power saving features are typically disabled.
Charged and on mains supply is how I generally killed my portables - it
runs faster when on mains so it generally is unless I'm travelling.
Deep discharged and left for a long period of time will brick it into a
state where safety features will (should) prevent it ever working again.
Even so you should cycle the battery to 20% or lower and then recharge
at least once a month. I have killed plenty of laptop batteries on
continuous power. The newer chemistry is a bit more robust but in search
of ever greater energy density that margin gets eroded again.
You need to cycle the battery every couple of weeks or so or the
chemistry will get stuck in a charged but forgotten how to discharge
state. That means when you do need to use it the remaining battery
capacity is a tiny fraction of its nominal rating. No problem if you can
always use it on mains power but a nuisance when travelling.
That sounds like decent advice. Although I rarely need to run on
battery power, it is worth having one that will actually run. I can buy
a replacement for my dead one, and implement a serious charging routine
based on the above.
Next question: Which battery suppliers are good, and which are to be
avoided? Or should I buy a proper Samsung battery?
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