Sudden and intermittent battery discharge with X60

[dc_slim]

I'm having an issue with a used X60 I recently bought. The battery, which is an 8-cell, will suddenly discharge, intermittently, unpredictably, under different conditions. The most common scenario is for it to hit about 90% capacity, and then drop immediately to 4 or 5%. It doesn't matter whether the machine is sitting on my lap, on a table, or being moved around -- happens under all those conditions. At other times, the battery will drain down further, and then discharge to about the same level.

The battery is virtually new, and rated by battery maximizer as being in good heath. Still holding almost all of its rated capacity. I'm thinking this must be a problem with the battery itself -- a short, or maybe multiple bad cells. Has anyone else had this problem? Or experienced similar behavior? I'm going to try to get my hands on another battery as soon as possible, but I though I'd post here while the details of the issue are fresh in my mind.

[Harryc]

I'm agreeing with you on the possible short or multiple bad cells idea. I have seen this exact behavior before turn out to be a bad battery. While I am confident this is the problem, wait for more answers before you replace it though.

[dc_slim]

Thanks for the input, Harry. Looking forward to hearing any other opinions that may be forthcoming.

[Marc_G]

My guess is that it is a problem in the circuitry that REPORTS the battery capacity, rather than a short in the battery itself.

If a thinkpad battery actually went from 90% to 5 % in a matter of a few seconds, there would be a smoking hole where the computer used to be. 60Wh or whatever represents a lot of energy. I sincerely doubt the battery itself is actually shorting out and discharging.

However, whatever the cause, the answer is the same: time to replace the battery. Is the machine under warranty?

Also, if you have access to another battery, try it for a while and see if the problem goes away. This would rule out some issue on the computer side.

Marc

[dc_slim]

Marc, your reasoning seems sound to me. Yes, the machine is still under warranty, fortunately. Unfortunately, I don't have another battery on hand. I'm trying to get my hands on one to test, though. Will let you know what I can determine.

[dc_slim]

Marc, it looks like your diagnosis was dead on the mark. Well, close actually. I don't think it's the circuitry, but rather the part of the BIOS that monitors the power level.

Here's what I found: I haven't been able to get my hands on another battery, so I set up a flash drive to load a live install of Ubuntu. (This is a useful data-recovery trick, and I'm finding more uses for it all the time.) While running Ubuntu, the battery drained all the way down to 50%, twice, without a "discharge" happening. A few web searches determined that the problem I described sometimes happens under Win XP. Basically, the ACPI misreads the battery level, and the appearance of a battery discharge is the result. Updating the BIOS is one a common fix, although my machine has the latest BIOS, so that's not the issue here. In my case, since I did not yet have a lot of software loaded on the machine and had not transfered my files to it, I just did a full restore off the HPA. Definitely not the slickest way to fix the problem, but straightforward and simple, if time-consuming. Also resolved my concerns about driver conflicts that might show up in the future.