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Re: power management problems

On Fri, Sep 14, 2007 at 02:13:32AM +0530, Ritesh Raj Sarraf wrote:
> rrs@learner:~$ cat /proc/acpi/battery/BAT0/info
> present:                 yes
> design capacity:         4800 mAh
> last full capacity:      1003 mAh
> battery technology:      rechargeable
> design voltage:          11100 mV
> design capacity warning: 480 mAh
> design capacity low:     145 mAh
> capacity granularity 1:  48 mAh
> capacity granularity 2:  48 mAh
> model number:            DELL YF0806
> serial number:           2004
> battery type:            LION
> OEM info:                SMP
> > How long does your laptop actually run before the battery drops off?
> AFAIU, 5-10 minutes. I noticed is that when on battery, the battery monitor
> quickly starts draining from full to half. Once it is half, all of a sudden
> it goes to like 5% remaining and I get a warning. And then my machine tries
> to hibernate.
> If hibernate is disabled, it will wait for another minute and then just
> power off.

Your battery holds a charge of 1000 mAh, and sends a warning at 480 mAh.  
That's consistent with changing to a warning mode at half power.
Maybe, in a fit of conservatism, the software that sends the warnings 
calculates against the design charge?  

My battery reports 
	design capacity:         6600 mAh
	last full capacity:      2784 mAh
	design capacity warning: 278 mAh
	model number:            DELL D0093
which seems more sensible.  I'm running kernel 2.6.18-5-686.  It may
be this is calculated onboard the battery; I don't know how to check.

At any rate, your battery is only holding 20% of its design charge.
Even if you fix this you may need a new battery soon.  It might be
less headache just to buy one now.


Rob Mahurin
Dept. of Physics & Astronomy
University of Tennessee 	phone:  865 207 2594
Knoxville, TN  37996   		email:	rob@utk.edu

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