Getting The Most Out Of Your Laptop Battery Means Ditching This Common Myth

The opening brief in Saturday’s newsletter included a bit of advice about unplugging your laptop, but we thought the topic deserved a little more attention. So if you’re one of the many folks who have bought into the notion that it’s a good idea to keep your laptop battery charged at 100% all the time, let’s dig into why you’ve been misled.

It’s time to unplug

To understand the fallacy of the myth about keeping a laptop plugged into an outlet all the time, it’s important to know a few things about the batteries that power them.

A lithium-ion battery operates most efficiently when the number of ions are evenly divided between its twin layers of cobalt and graphite. But when it is charging, even after reaching 100%, the majority remain concentrated in the cobalt layer, which limits the battery’s life over time.

“So when you take it off and expect it to last for eight or 10 hours, it might only give you half of what you expect because it degraded a lot during that time,” explained professor Kent Griffith.

Instead of continuing sending power to the battery, it’s much better to unplug it and allow your laptop to remain in the 20% to 80% range most of the time to get the longest battery life possible.

But it seems logical

There are some seemingly good reasons that people believe laptops should be plugged in virtually all the time. In the days of desktop dominance, for example, there was no option to unplug.

It’s also a bummer when a laptop dies, so some people want to avoid that by ensuring it is always being charged. But if you do this, your battery will only drain much quicker when you actually do want to use it on the go.

Chris Agee March 25th, 2024

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