Your iPhone battery is not designed to stay at 100% for long periods. Lithium-ion batteries work best when they stay between 20% and 80%. Once a battery reaches full charge, it remains under stress, which speeds up its aging process. The more often this happens, the quicker its capacity degrades.

While your iPhone manages charging efficiently, keeping it plugged in overnight or frequently topping it off to 100% can lead to long-term damage. If you want to keep your battery healthy for years, it is best to stop charging before it hits full capacity.

How Optimized Battery Charging Helps

Apple knows that battery lifespan is just as important as daily battery life. That is why iPhones include Optimized Battery Charging, a smart feature that reduces battery stress. When enabled, it learns your charging routine and delays charging beyond 80% until you actually need it.

For example, if you plug in your iPhone overnight, it won’t charge straight to 100%. Instead, it stays at around 80% for most of the night and completes the last 20% right before you wake up. This minimizes the time your battery spends at full charge, helping it last longer.

Set a Charge Limit for Better Battery Health

If you want even more control, Charge Limit is another feature to protect your iPhone battery. Available on iPhone 15 models and newer, it allows you to cap charging at a specific percentage between 80% and 100%.

You can enable this by going to Settings → Battery → Charging and selecting a preferred limit. Even setting it at 95% instead of 100% can help extend your battery’s lifespan. Apple even recommends this setting based on usage patterns.

Limiting your charge helps reduce the wear and tear on your battery over time. Since lithium-ion batteries have a limited number of charge cycles, keeping your phone from constantly reaching full capacity slows down degradation.

If you plan on keeping your iPhone for several years, using Charge Limit can help it hold a charge longer, even as it ages.

Should You Ever Charge to 100%?

Charging to full occasionally is not a disaster. Modern iPhones manage battery health well, so reaching 100% from time to time won’t cause immediate harm. Apple’s software also prevents overcharging by stopping the charge once it is completely full.

However, keeping your phone at 100% for long periods does wear down the battery. If you use Charge Limit, your iPhone may still hit 100% sometimes. This happens to keep battery estimates accurate, but it won’t occur too often.

Maximize Your iPhone Battery’s Lifespan

To get the most out of your iPhone battery, focus on habits that reduce strain. Enable Optimized Battery Charging, set a Charge Limit, and avoid constantly topping off to 100%. These small changes can make a big difference in keeping your battery healthy for years.

It is also a good idea to avoid letting your battery drop too low. Extreme levels – both 0% and 100 – put stress on lithium-ion cells. Keeping your iPhone charged between 20% and 80% is the sweet spot for long-term battery health. By managing your charging routine, you ensure your device runs smoothly for as long as possible.