Extending Laptop Battery Life

There are ways to help your computer's power supply last longer, but store the batteries carefully when they're outside the machine

Reader Wayne Powell wants to know how to extend his computer's battery life. My daughter and I have laptop computers that run primarily on AC current, using battery power only occasionally, such as during travel. Would it be better to remove the battery when we are using the AC power exclusively, to reduce the constant charging/recharging of the battery? I realize we would have to remember to put the battery in to fully charge before a trip and that could be a problem, but if it extends the battery life by a couple of years I would be willing to try it. Both computers are less than two years old.

Yes, your batteries will live longer if they are removed from the laptop when it's plugged in for long periods of time. Unlike some older battery types, lithium-ion batteries are designed so that they cannot be overcharged if left plugged in. Still, maintaining the battery at full charge for extended periods can shorten service life.

Should you opt not to remove the batteries, but run the laptop so that it is nearly always plugged in, it's a good idea to remove the charger cord every once in a while—say, at least once a week—and run the computer off battery power for an hour or two. Drawing down the battery and recharging it from time to time extends its life. Some notebooks have software that is supposed to simulate this process by shutting off the charger occasionally, but I have not found it to work very well.

If you do remove the battery, you'll want to protect both the laptop and the battery from short-circuits when the battery is outside the computer. Most laptops are designed so that the battery contacts are well-protected, so that isn’t too much of a problem. However, you do want to store the battery carefully so that a stray conductor, such as a paper clip or other piece of metal, cannot short the connectors. You could keep it in a box or a bag or just put masking tape over the contacts. At a minimum, contact with the wrong item will ruin the battery and, at worst, could cause dangerous overheating.