Q: I have a Acer AOD260 laptop that is about 3 years old. Recently I have noticed that my battery is acting weird. When I plug my laptop in, it only fills up to an 87 percent charge, and then it says "plugged in, not charging," and it will not charge the battery to 100 percent. After I unplug the laptop and use it for a couple of hours, it will drop down to where I have about 30 minutes of use left. Then the computer just shuts down. Is my Acer al10a31 Battery going bad?

A: When it comes to portable electronics like laptops, cellphones and such, the batteries tend to be the things that wear out before just about anything else.

In my experience, the life expectancy of laptop batteries tends to be about two or three years. After that, it is not uncommon to see the battery lose its ability to charge fully or even report that it is fully charged and then lose the charge in minutes. And the behavior in which the laptop just shuts down, even though it shows it still has 30 minutes of charge left, also is common with a failing battery.

Laptop batteries are usually not covered by the manufacturer's warranty, so you are looking at purchasing a replacement. While it is too late for this battery, there are steps you can take to get the most life out of any new batteries you acquire.

Whenever I get a new portable device like a phone or a laptop, I "train" my battery, by plugging the new device into a wall socket and charging the battery completely. I then let the battery run down completely, charge it again, and drain it one more time. I have found that this process will make the battery hold a charge longer than a battery that has not been "trained." For my Android phone I have two batteries - one I trained and one I didn't. The trained battery will hold its charge for up to 30 percent longer than the untrained battery.