Battery capacity up by 2 Wh

[G2007]

Just thought I'd share this. I know some people have said that "deep discharge" of the battery is not helpful, but yesterday, I unknowingly allowed the battery to run down to 1%.

Upon recharge, my full charge capacity had increased by approx. 2 Wh.
After 94 cycles, my fcc is currently 41.61 Wh, which seems to be pretty good relative to what others have remaining.

[Kenn]

Just thought I'd share this. I know some people have said that "deep discharge" of the battery is not helpful, but yesterday, I unknowingly allowed the battery to run down to 1%.

Upon recharge, my full charge capacity had increased by approx. 2 Wh.
After 94 cycles, my fcc is currently 41.61 Wh, which seems to be pretty good relative to what others have remaining.

It's not just your thinkpad, it's happening on Mars too!

Mars Rover Get Mystery Power Boost:
http://www.space.com/news/rover_mystery_041105.html

"The rovers had available about 1,000 watt-hours a day when they arrived on Mars, but dust on their solar panels and the seasonal decrease in solar energy have limited their power, and therefore their activities.

Opportunity is now at about 820 watt-hours and remains very close to full capability. Spirit, which is in a less advantageous position to point its arrays toward the sun, has 350 to 400 watt-hours daily. "

[bapatterson]

Interesting stuff.

Silly question: how do you determine how many watts your battery has?

[zzyss]

Click on the Battery Maximiser icon, then select Battery Information. On that screen, select the Battery Health button, and there should be some statistics about your battery, including the Wh's.

[erasmus]

I think its just a matter of calibration. Have a look at:

http://www.batteryuniversity.com/parttwo-34.htm

All the stuff you need to know about Li-Ion batteries. Still a deep discharge is only recommended occasionally.

[G2007]

I think its just a matter of calibration. Have a look at:

http://www.batteryuniversity.com/parttwo-34.htm

All the stuff you need to know about Li-Ion batteries. Still a deep discharge is only recommended occasionally.

You could be right. For one, my system remained on while the battery was at 1% for an inordinately long time, which indicates it was not really at 1% remaining capacity.

Also, while my battery has lasted longer since the increase, that could just be because I haven't run it down very low. In other words, going from 100% to 20% correctly calibrated will provide more run time than before, though if I were to now run the battery down to 1%, it would probably shut off quickly.

I think IBM recommends deep discharge 1 once a month (that site recommends dd every 30 cycles).

[brewt]

From what I've read, the deep discharge is pretty much so that the battery circuitry and recalibrate itself. However, deep discharges aren't good for the battery since you can possibly run down a single cell in the battery too low, so it isn't good to do it too often.