Tech Tip: Battery Life

Rechargeable batteries power all of the electronic devices I use most: My camera, laptop, cell phone, and even my beard trimmer. We've all had devices whose batteries have lost their charge capacity over time, some much more quickly than others. With a bit of care, it's possible to extend the lives of these batteries much longer than you may think. For basic guidance, Apple has a great set of maintenance and care instructions on their site. (While that particular page is specifically about notebook batteries, the information is applicable across the board.) For those looking to really push the limits of a battery's lifespan, there are a few tricks of the trade that you won't find on the Apple site.

In case you're wondering just how much of a difference this kind of maintenance can make, my MacBook Pro is a great example. I'm particularly anal about caring for my battery, but at nearly six months old, my laptop actually holds more of a charge than it did the day I took it out of the box. If you have a Mac laptop, you can use this tiny application to see how your battery is doing. If your score is lower than you'd hoped, don't worry! You can actually improve the capacity of your battery by following the steps below.

The most important thing to remember about batteries is that they need to cycle the electrons they store in order to maximize their capacity over time. You can think about it like the glass of water you keep next to your bed: You probably don't drink the whole glass over the course of a night, but if you just keep adding fresh water to what's left over, the whole glass of water is going to get nasty over the course of a couple of days. It's much better to dump out the leftovers and start over with as fresh a glass as possible. In other words, let your computer die before you plug it back in. Waiting until you see the low battery warning isn't enough: Let it die completely. And once you plug it in, it's best to let the battery fully charge before it's unplugged. The more strictly you follow these rules, the longer your battery will last.

If you want to get the absolute most out of your battery, you can take steps to drain it even more than it typically will with normal use. As a security feature, your laptop will use what it deems to be its last bit of juice to safely store everything you're working on and begin to hibernate. This minimizes the chance of data loss as a result of sudden power failure. It's a handy feature if you're working on an important document, but it also means that your battery seldom cycles the electrons stored in the very last of its cells.

The trick to really killing your battery is straining your system prior to hibernation. By running programs and processes that take a great deal of battery power, you're more likely to reach even deeper into the depths of your battery's cache before the system shuts down. My preferred method is to crank up the brightness of my display and, using iTunes, play music through my laptop's speakers while running the music visualizer. (On a Mac, you can activate the iTunes visualizer using Command+T.)