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battery phsychology

Posted: Tue Nov 28, 2006 2:28 pm
by veldren
It appears to me that since everyone has an opinon on how to take care of Li-Ion batteries that vary greatly, so I have come to a conclusion that this seems to be just like the field the phsychology. But I hope someone can make sence of my problem. =/

IBM's battery software told me to "recondition" my battery which was yellow at the time. I followed the steps precicly by allowing my computer to completely deplete all charge from my battery 4 times. This just made things worse. Eventally I had to get a new battery and decided to listen to the forum posters. I never let my laptop battery go below 50% power, and I hardly use it in battery mode (I keep in pluged in whenever possible). And I of course have it set on longest battery life settings, when I use the battery. Few months later the exact same thing is happening again! My battery is currenly "yellow" 57.40wh out of what should be 73.26 wh design capacity.

Check out these scary stats, and cycle count is not a typo

Device Chemistry Li-Ion
Full CHarge Capacity 57.40Wh
Design Capacity 73.26Wh
Cycle Count 0
First Used Date 2006-09

I am starting to think something maybe wrong with my laptop, not the battery. I checked charging adapter and it was trinkling in 16.67 volts, so I think thats fine. What am I doing wrong?

Posted: Tue Nov 28, 2006 10:21 pm
by christopher_wolf
Welcome to the Thinkpad Forum. :)

If you haven't recalibrated the battery, or run it down to somewhere under 10% and charge it back up, then it technically will not have gone through any cycles and the gauge is correct. Although it is a bit concerning that the battery is losing capacity that fast and, ruling out extreme temperature and humidty conditions, might indicate a problem with how it is charged and whether or not there is a lessening in the charge current when the battery hits a charge threshold to preserve life. How many months is a "few," by the way? :)

Re: battery phsychology

Posted: Wed Nov 29, 2006 6:28 am
by tomh009
veldren wrote:Device Chemistry Li-Ion
Full CHarge Capacity 57.40Wh
Design Capacity 73.26Wh
Cycle Count 0
First Used Date 2006-09
As Christopher says, you need to run it down at least once to calibrate. And reconditioning (which can also be done manually, by fully charging, fully running down, and repeating) will help the battery unless it is on its last legs. How old was your old battery when you tried the reconditioning?

As a point of comparison, here are my battery stats. I run on battery, I run on AC, I charge, I discharge, but aside from a very occasional reconditioning cycle, I just use my ThinkPad wherever and however it's most convenient -- no babying the battery! And yet it's doing very well relative to its design capacity, when you consider the cycles.

Device Chemistry Li-Ion
Full Charge Capacity 36.92Wh
Design Capacity 47.52Wh
Cycle Count 681
First Used Date 2005-02

Posted: Wed Nov 29, 2006 1:35 pm
by veldren
Thanks for the feedback Chris. I have run it down once to 3%. After that I noticed the battery went down a few watt hours for it's max charge. I'll try to run it down again and I'll post my new stats. I received the battery in late Sept, so that makes the battery 2 months old. I would return the battery but I have a feeling this problem is going to repeat itself.

As for enviormental, laptop is on my desk most of the day with its internal fan operating correctly. Laptop just gets warm at most, never hot. Also note I never take the battery out of the laptop.
Any ideas?

Posted: Thu Nov 30, 2006 2:49 am
by veldren
This time I disablied the system from going into standby and completely drained the battery then fully recharged it and took this reading. As you can see I gained 1 cycle and lost little over 2Wh from just doing that so called "reconditioning". Any thoughts/suggestions? Thanks

Device Chemistry Li-Ion
Full CHarge Capacity 54.56Wh
Design Capacity 73.26Wh
Cycle Count 1
First Used Date 2006-09

Posted: Thu Nov 30, 2006 3:25 am
by christopher_wolf
Well, that is certainly a bit strange. That is how I have used my T43 and the battery is from 2003 with 178 cycles on it, giving near 4:05 hours of battery runtime on adaptive.

Normally, you aren't supposed to "deep cycle" a LiIon battery as that will increase the wear level, but that is exactly what the recalibration through the Power Manager does.