According to many tech experts, including Sean Carrigan, CEO of MobileQubes, charging your iPhone overnight is one of the worst things you can do to your battery.
“This action will overload your battery and ultimately chips away at your battery’s life span,” Carrigan says. “Your phone has a lithium-ion battery that functions at its best when kept at a consistent charge between 40 and 80 percent, so by overcharging your phone the battery will be unnecessarily taxed and will not only shorten its lifespan but can rise to a temperature that can threaten your safety.”
If you’re wondering how much damage a few overnight charges can actually have on your phone, it’s probably more than you think.
“It is tempting to charge your iPhone while sleeping because of convenience,” says Sandra Henderson, a Licensed Professional Counselor at LifeHacks. “However, overcharging your iPhone is the worst mistake you can make because it reduces the lifespan of your iPhone from 4 years and 3 months to 2 years with battery capacity problems.”
Overcharging can actually reduce your iPhone’s battery capacity by 25%. “To avoid destroying the battery efficiency of your iPhone, charge it as soon as the battery icon shows 10% and unplug it from the energy source when it hits 95%,” Henderson says.
The best charging method is to provide periodical charges when your phone dips down around 10 to 20 percent (but avoid letting the battery drain completely). And if that’s not possible, another great option is to connect your phone to a Smart plug that you can set to a schedule. The charger will automatically turn off and you’ll avoid overcharging your device — without the hassle of having to give it a moment's thought.