x120 thinks battery is critical

I've owned it for about 2 weeks now, and on around 3 occasions, while unplugged and with plenty of battery remaining, it will simply hibernate itself for no reason. Upon turning it on, windows 7 says battery was critical, make sure plugged in, etc. Battery is always fine though, and I continue on as if nothing had happened.

On another occasion, where this didn't happen, I noticed my power manager icon briefly flickering, and changing to AC mode, while I wasn't plugged in. it stayed that way for a few seconds, then went back to battery mode. nothing else unusual happened.

I will try disabling power manager, but could that even have an effect on this? This happens when I'm not really doing much, just typing with it on a table. Could it be a hardware problem?

 

Try updating your BIOS to the latest version and disabling or uninstalling the Lenovo Power manager. If that doesn't help, it may well be a hardware issue.

 

Have you tried using the system without the battery inserted (just AC plugged in). If it seem OK without it then I would suspect the battery to be playing up with the system.

If its under warranty then I would notify the issue with Lenovo and hopefully they can send you a replacment.