Question ASUS UX31A shuts down on battery power with 40% left

[SimonK2]

I have a 2012 ASUS UX31A, unmodified. It has recently begun crashing when on battery power with about 40% of battery charge left, rather than warning me about low battery levels at a much lower level. I am using the default Balanced power management scheme. What can I do to regain the warning about low battery level rather than the crash?

 

[velocityg4]

It sounds like the computer can no longer get an accurate reading of the battery. This generally is a symptom of a dying battery. Given it's age. This isn't surprising.

You'll have to decide if it's worth repairing given it's age. Also many aftermarket batteries are junk that fail shortly after purchase. Unfortunately there aren't any big aftermarket battery names.

 

[SimonK2]

I thought that might be the case. I bought an ASUS replacement battery a couple of years ago but never installed it as the original one didn't seem to be losing much performance ... until this symptom appeared. I have had the experience of a "NoName" replacement battery failing after a few months in another laptop. I put it down to the fact that the batteries have a limited shelf life so if you install one that's already many years old you won't get much from it. As my ASUS replacement battery has a production date of May 2012 perhaps I shouldn't expect too much from it and should get another machine.

 

[SimonK2]

Took the plunge and installed the replacement battery (which turned out to have a manufacture date slightly before the one which I removed!) in my UX31A and I am now down to 19% battery without the machine crashing so velocityG4's comment looks to have been dead right. What I am seeing is the difference between a battery having had no charge/recharge cycles and one which had many ( I forgot to count them on the old battery). The UX31A has been mostly operated on mains power over the 7 years I've had it, but there would have been a fair number of battery operation periods. So it seems that comments about Li-ion batteries only lasting 2-3 years if not used are not correct. The capacity of the 7 year old battery is certainly less than a more recent one (if studies are to be believed) but it seems to have enough performance not to trigger machine crashes and I think the period of machine operation is much greater.