VOGONS


First post, by keenmaster486

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I pulled out an old Dell D600 laptop this week that has been sitting for some time - at least a year. Its battery was replaced something like five years ago. I plugged it in and it didn't seem to have any idea what it was doing with the battery, giving very strange readings and saying it's discharging or idle when it's not, or getting stuck at 60%, etc. I decided to do an experiment and let it sit for a couple days off but plugged in. I started it up and the meter read 100% on the battery. I then unplugged it and let it sit until the battery ran out. It immediately dropped to 60%, then 36%, then 12%, and then 0%, in big jumps like that, before quitting entirely. It lasted about 7 minutes. I plugged it back in and let it sit until the meter read 100% again. This time after unplugging it, the meter quickly fell to 0% again, but in reality it lasted for a whole hour! So obviously the meter was wrong. I charged it back up to 100% again and again unplugged it. The meter fell to 0% again but it is again sitting there working just fine. It's been that way for about 40 minutes and I suspect it will last longer than an hour this time.

What is going wrong here? I think the battery meter is horribly miscalibrated, but how do I fix that?

World's foremost 486 enjoyer.

Reply 1 of 2, by nforce4max

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Lithium ion batteries do odd things as they age due to forming copper shunts inside the cells, changes in temperature can sometimes revive them so they can return from the dead and work as if nothing had happened then eventually die again.

On a far away planet reading your posts in the year 10,191.

Reply 2 of 2, by keenmaster486

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Hmm... well, here's an update: it only lasted an hour, again. But not less than the previous time.

I think my issue has to do with power meter calibration. But there is no option in the BIOS to calibrate anything battery-related.

World's foremost 486 enjoyer.