Sure, the 80% charge limit is a great little feature on iPhone and iPad, but it’s not an ideal solution when you take heat into account.
We do Have 80% Charging Limit on iPhone and iPad, But What we Really Need is a Charge Speed Limiter to Reduce Heat
No matter how you slice it, the thing that ruins your battery health the most is heat. You can use 80% charge limit all you want, but if your device is getting too hot while charging, the 80% charge limit is not doing you much favor. It gets worse when you are charging wirelessly.
The point of the 80% charge limit is to put the least amount of stress on the battery, but if you’re an OtterBox sort of person, you’re slowly destroying your iPhone and iPad battery, thanks to heat generated and trapped inside the case. Instead, Apple should allow users to limit charging speed using software. It already does this when battery hits the 80% mark. Once that mark is reached, charging cuts off completely until the iPhone cools down a little and then it continues to 100%.
Rather than charge at maximum speed and generate heat, the user would limit the charge rate to just 5W, 10W, 12W or 15W maximum. Even with high ambient temperatures, the device would stay relatively cool compared to full speed charging.
Fast charging is all well and good, but you can’t fight physics. Charging at fast speeds causes heat and there is nothing much you can do about it. Charging without a case is one option, but the most effective thing is slow charging.
You can literally just use a 5W charger to charge up your iPhone right now and you’ll notice it doesn’t get warm at all. The charging speeds are going to be awful given how big the batteries have gotten inside our iPhones, but little to no heat means battery health longevity.
Another problem is, fast chargers have become extremely common these days. You’re sold a fast charger by default at this point. For example, if you just ask a Genius working at the Apple Store for an iPhone charger, they’ll hand you the 20W USB-C charger. Wouldn’t it be just better if you buy that fast charger and you get to choose how fast you want to charge?
I know for a fact iOS 18 and iPadOS 18 doesn’t include the feature to limit charging speed. But, it will tell you if you’ve been using a slow charger to charge up your device. Who knows iOS 19 and iPadOS 19 might just include this feature.
Apple, if you’re reading this, make it happen. A lot of people want to hold onto their iPhones and iPads for longer.
