lkml.org 
[lkml]   [2008]   [Jan]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: kpowersave stuck at battery charging
Andrey Borzenkov wrote:
> On Wednesday 02 January 2008, Alexey Starikovskiy wrote:
>
>> Andrey Borzenkov wrote:
>>
>>> This is did not happen before; I am not sure right now what caused this
>>>
> (i.e.
>
>>> battery aging or some software change) nor whether this is
>>>
> kernel/HAL/kpowersave
>
>>> issue.
>>>
>>> kpowersave is stuck at assuming battery is loading and at 94%. Sysfs
>>>
> displays
>
>>> battery state as Full:
>>>
>>>
>>>
>> Frequent battery charging shortens lifetime of the battery, so some (may
>> be all now)
>> notebook manufacturers do not start charging battery until it discharge
>> to some degree (~90%).
>>
>
> I thought Li-Ion batteries do not have memory effect. Actually I remember to
> have read recommendation to avoid deep discharges of Li-Ion battery, it was
> adviced to charge it as often as possible.
>
IBM has advice to not re-charge battery until it discharged to 95%.
It was implemented in their batteries/notebooks.
There is no memory effect in Li-Ion batteries, there is only limited
number of
charge cycles -- about 1000 times, thus "as often as possible" is advice
of the battery seller :)
>
>> It could be your case. Please try to discharge battery to, say, 89% and
>> then check if it charges to the
>> 100%.
>>
>
> That is exactly the question - how do you compute 100%? As far as I can tell the
> only possibility is - when battery stops charging. At this point you have to
> assume battery is fully charged.
>
Last charge would be good reference. Think of the battery as constantly
degrading resource.
> I tried to discharge battery (it was around 78%) and plug AC in again. It went
> on Charging until the same limit after that state changed to Full (well, in case
> of ACPI battery we really only can state - not (dis-)charging, there is no
> special Full state flag); kpowersave still believes battery is not fully
> charged. Main interface shows 84% (no Charging) - tooltip states it is being
> charged.
>
>
So, that is the state of your battery. If you buy new one, it will go
high again.

Regards,
Alex.


\
 
 \ /
  Last update: 2008-01-02 17:21    [W:0.087 / U:1.332 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site