What You Should Know About Wireless Charging

Wireless charging is a convenience eagerly sought by consumers wanting to do away with cumbersome wires. More users are taking advantage of wireless charging pads at home and increasingly, wireless charging pads in vehicles, to recharge their smartphones and other portable electronics. But this video on the DIY electronics site iFixit suggests wireless charging is not always a good idea.

According to the video, wireless chargers are not as efficient as wired chargers, and some wireless chargers can potentially ruin the batteries in portable devices. The narrator explains that at best, even the most efficient wired chargers lose up to 35% of their energy during normal operation. He also pointed out that during IFixit’s charging tests, the battery’s temperature never exceeded 29◦C.

The video noted that with wireless charging pads, the need for the pad to generate a magnetic field to induce charging current wastes a lot of energy. That, along with issues such as alignment, decreases charging efficiency. Technologies such as Apple’s MagSafe and the Qi2 standards partially mitigate alignment issues, and are features the video says consumers should look for when purchasing a wireless charger.

Still, those technologies do not completely solve the problems of charging efficiency and temperature. The video noted wireless chargers use 36 percent more energy than wired chargers. At the same time, during iFixit’s tests, the battery’s temperature peaked at 35◦C. Those are best-case figures assuming optimizing factors such as portable device alignment.

Finally, in perhaps a veiled dig at Elon Musk, the video noted that tests of Tesla’s Wireless Charging Platform resulted in extended charging times, poor charging efficiency, and worst of all, a very hot battery.

You can view the video here.