new laptop battery problems

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I recently bought a new laptop and I noticed that
the battery won't charge up to the full capacity
(or as it says design capacity).

$ cat /proc/acpi/battery/BAT1/info

present:                 yes
design capacity:         4400 mAh
last full capacity:      3040 mAh
battery technology:      rechargeable
design voltage:          14800 mV
design capacity warning: 300 mAh
design capacity low:     100 mAh
capacity granularity 1:  32 mAh
capacity granularity 2:  32 mAh
model number:            03ZG
serial number:           30030
battery type:            LION
OEM info:                SANYO

$ cat /proc/acpi/battery/BAT1/state

present:                 yes
capacity state:          ok
charging state:          charged
present rate:            0 mA
remaining capacity:      3040 mAh
present voltage:         16544 mV

First when I noticed this it stopped charging at 3400 mAh,
I've been trying different things like emptying/recharging
(about 8-10 times), removing/recharging, but as you see
it only became worse.

Will this fix by itself (I read that new batteries sometimes don't
charge to full capacity, but in this case the full capacity is
becoming lower and lower)?

Re: new laptop battery problems

Well a new Lithium Ion battery require to be conditioned before use and
you have certainly tried it 8 - 10 times.

In my experience, I can safely say that the battery is faulty.  It is
working but not delivering the full capacity.  Since its new, you
should get a straight swap.

If the replacement behaves the same way, then there may be a setting on
the laptop that I have not come across before!! or a fault on the power
circuitry on the laptop.

Hope this helpful.

Battery Wizard

Re: new laptop battery problems

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Present voltage 16544mV or plainly 16.544V sounds a little odd when
the designed voltage is 14.8V is this a battery fault or a charger
fault, think I would look at the charger first ..?

Reason is I never  hear of overcharging with the Nicad variety
although they 'are' different, a point that never been raised.....?


Re: new laptop battery problems

Davy wrote:
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I noticed that too.  When the battery is discharging, the voltage
becomes lower, even under 14,8 at the end.  Maybe I should
take the whole laptop to the service?

Re: new laptop battery problems

On Mon, 20 Feb 2006 12:30:29 GMT, no@spam.invalid (Davy)

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Typically a nominal voltage is 3.6 per cell but higher, as
much as 4.2 charged.  Compare NiMH like this and you see a
supposed 1.2V cell is actually closer to 1.4V charged.

So with a 1.44/14.8 range pack that's 4 x Li-Ion cells in
it.  4 x 4.2 = 16.8V, it's pretty close to what we'd expect
to see, EXCEPT for that part about insufficient capacity.

Re: new laptop battery problems

Point is, you go out and buy a new battery if it happens to be the
charger then
you are in the same predicament with a 'hole in the

These chargers are
so well regulated, no doubt also contains
overcurrent protection as well, what
happens if the regulator ain't

This is what I feared and why I
posted, it may well be the battery but
I doubt it, the tell tale is the 16.544
Volts and doubt that is a
trait of Lithium Ion batteries, there are dedicated
battery testers
for this very purpose but they are quite expensive, these things
aren't testmeters as we know but can even tell you the discharge rate

When a battery near's the end no matter what battery it's the internal
resistance that rises causes a voltage drop as current is drawn
through this
generated internal resistance, some types of battery
have varying 'knee
characteristics', the ability to produce the
required voltage as it nears the
end of its life, some are better
than others at doing this.

Mind you I could be
wrong, good luck all the same.


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