The Surprising Reason Why Fast Chargers Are ‘Killing’ Your iPhone Battery Life: ‘Absolute Worst Thing’

There’s a reason Apple gave out really tiny charging blocks when they first issued the Apple phone. The past charges only charged at 5 watts, which might be too slow for some people, but there’s a reason not to discount slower chargers. Apple’s current chargers charge at 20 watts, which is much faster, but this comes at a cost. When you use a higher wattage charger, it’s going to charge your phone faster, but it’s also going to make your phone heat up. This includes heating up your battery.

The iPhone’s lithium-ion battery is extremely sensitive to temperature. It’s recommended that you only ever charge your device in room temperatures, for example, to minimize the impact extreme heat or cold can have on your battery. If you are the kind of iPhone user who is only charging your phone once a day, sticking with a slower 5-watt charger will still get the job done (especially if you charge it for hours at a time, such as overnight) and won’t place excess stress on your battery.