Got a new iPhone? Here is the one battery setting you need to fix now.

Your iPhone battery is a consumable item, just like any other battery. The more you take care of it, the longer it will last, and the better your performance will be. 

What is the most effective thing you can do to improve your battery health?

The best thing to do is to limit the charge on your iPhone’s battery. Starting with the iPhone 15, you can limit the charge of your iPhone to 80%, so it does not charge beyond that setting.

When you charge beyond 80%, you will start to generate more heat while charging, which will degrade the battery’s health. You will get more battery life in the short term, but at the cost of battery health in the long run. 

I have been using an iPhone 15 Pro Max everyday since October 2023, and I have 99% battery health on my iPhone. I have my charging limit set to 80%, and that is why it has stayed in excellent condition. 

The real kicker? I have been using MagSafe wireless charging 99.9% of the time. 

I have lost 1% battery health in 11 months of daily use while charging wirelessly.

Wireless charging is less efficient than directly plugging in your phone to charge, but MagSafe is more efficient and smart compared to just a standard Qi wireless charger, and overall generates less heat if you go wireless.

If you are a regular user like me who uses their phone for social media, Youtube, email, and everything non-game related, you should achieve similar results by setting your limit to 80%.

Here’s how to do it:

Go to Settings → Battery → Charging.

Under charging, you can set your charge limit from 80% to 100% in 5% intervals.

The lower your charge limit, the longer your battery will last since it will generate less heat.

This is critical for most people who keep their iPhones for years. If your battery ages prematurely, you will have performance issues, and might not even be able to complete certain tasks that require significant battery power. 

Here is Apple’s more thorough explanation of battery health:

For a phone to function properly, the electronics must be able to draw upon instantaneous power from the battery. One attribute that affects this instantaneous power delivery is the battery’s impedance. A battery with a high impedance might be unable to provide sufficient power to the system that needs it. A battery's impedance can increase if a battery has a higher chemical age. A battery’s impedance will temporarily increase at a low state of charge and in a cold temperature environment. When coupled with a higher chemical age, the impedance increase will be more significant. These are characteristics of battery chemistry that are common to all lithium-ion batteries in the industry.

When power is pulled from a battery with a higher level of impedance, the battery’s voltage will drop to a greater degree. Electronic components require a minimum voltage to properly operate. This includes the device’s internal storage, power circuits, and the battery itself. The power management system determines the capability of the battery to supply this power and manages the loads to maintain operations. When the operations can no longer be supported with the full capabilities of the power management system, the system will perform a shutdown to preserve these electronic components. While this shutdown is intentional from the device perspective, it might be unexpected by the user.