Simple iPhone Settings and Habits That Help an Old Battery Last Longer

An older iPhone does not have to die by midafternoon. CNET rounded up Apple's own advice for slowing battery wear, and most of it is free. It comes down to one setting worth checking and a few habits around heat. Both could delay a battery replacement or a new phone.

Why batteries wear out

Every iPhone battery slowly loses its ability to hold a charge. The more you charge the phone, the more it wears. You can see the damage in the Battery Health settings, which show maximum capacity. New software features that use more power can make an aging battery feel worse. A replacement can cost real money if you lack the proper coverage.

Check one setting

You cannot overcharge a battery, but sitting at 100% puts it under some stress. Optimized Battery Charging helps. It learns your routine, such as plugging in at bedtime and unplugging in the morning. It then waits to finish charging past 80% until just before you need the phone.

The setting should already be on. To confirm, open Settings, then Battery, then Battery Health & Charging, and make sure Optimized Battery Charging is toggled on.

Keep it cool

Heat is hard on batteries. Higher temperatures speed up the chemical reactions inside, which makes the battery work harder and age faster. Apple says to keep your iPhone out of temperatures above 95 degrees Fahrenheit (35 Celsius) to avoid permanent damage.

• At the beach, do not leave the phone on a towel in direct sun. Use a bag or cover it with a shirt.
• Do not leave it in a parked car for long, especially on a hot day.
• If it runs hot while charging, take the case off. Bulky, protective cases can trap heat.
• Skip games and other demanding apps while the phone charges.

Apple builds in safeguards, such as disabling the phone or stopping charging when it gets too hot. Those are a last resort. It is better to prevent overheating than to wait for the phone to protect itself.

Putting an old phone away

If you are setting aside an old iPhone after upgrading, Apple has steps to follow first to protect the battery. The details were not included in the portion of CNET's article available here. One thing is clear: a phone stored for a long time may be at a low charge. You may need to charge it for about 20 minutes before it turns on.