Mobility

How wireless charging could ruin your iPhone battery

Wireless charging isn't good for iPhone 8 and iPhone X smartphones. In fact, it's wearing batteries out faster and could increase their chance of failure.

Building a slide deck, pitch, or presentation? Here are the big takeaways:
  • Wireless charging is causing iPhones to burn through battery charge cycles far faster than expected. —ZDNet
  • Wired charging switches the device to AC power, which gives the battery a rest, whereas wireless charging continually taxes the battery for power, resulting in quicker degradation.

Wireless charging is a popular feature of modern flagship smartphones. Apple users were clamoring for the feature, which was finally added in the latest generations of devices, the iPhone 8 and iPhone X, but using it might not be such a good idea.

Some research done by Adrian Kingsley-Hughes of our sister site ZDNet led to the startling realization that wireless charging, which Kingsley-Hughes tends to use, is accelerating the wear on his battery.

The end result, he surmises, is that wireless charging is killing his battery much faster than charging via cable.

How wireless charging is killing iPhone batteries

iPhone batteries are designed to retain 80% capacity through 500 charge cycles, which Apple defines as using 100% of a battery's capacity and recharging it to the same point, though not necessarily all at once. If, for example, you use 75% of the battery on Monday, recharge to 100% overnight, and then use 25% the next day you've completed a whole cycle.

Using a macOS app called CoconutBattery, Kingsley-Hughes was able to determine that his iPhone was burning through charging cycles far faster than expected. In just under six months of use, his iPhone had gone through 135 charge cycles.

SEE: Mobile device computing policy (Tech Pro Research)

For reference I tested my iPhone SE: In roughly a year of having it I've only used 103 battery cycles. By contrast, Kingsley-Hughes estimates if he maintains his current usage/charging habits, he'll pass 500 charging cycles in less than 18 months of use. I may not even get there before I turn mine in for an upgrade.

So why is that happening? It all has to do with how a smartphone charges. When plugged into AC power an iPhone battery is getting a rest: It's being powered by the cable, and all the battery has to do is charge and wait for the cable to be removed.

Wireless charging, on the other hand, doesn't give the battery a break. As data streams to and from a device, the screen turns on to broadcast alerts, or music is played, and the battery is continually topped off by the charger. Each little tick of the battery's capacity is another percent counted against the charging cycle, and another bit of wear and tear the battery has to deal with.

In short, your battery gets a break when it's plugged in, whereas wireless charging constantly uses, and therefore constantly stresses, it.

Non iPhone users, you're not safe either. Anything that charges wirelessly is experiencing constant battery stress, and the end result is going to be reduced lifespan. You don't need to necessarily stop using this latest and greatest mobile tech innovation, but limit it to top offs. Give your battery a rest in the evening and plug it in.

Also see

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Image: Mophie

About Brandon Vigliarolo

Brandon writes about apps and software for TechRepublic. He's an award-winning feature writer who previously worked as an IT professional and served as an MP in the US Army.

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