Swollen iPhone Battery: Warning Signs and What to Do

Quick answer

Warning signs include the screen lifting away from the frame, a gap along the edges, the phone rocking on a table, or a bulging back. Stop charging it, keep it somewhere cool and away from anything flammable, and don't press on it, puncture it or try to remove the battery yourself. Get the battery replaced as soon as possible.

Why batteries swell

Lithium-ion batteries can produce gas as they age, overheat or get damaged. The gas makes the battery puff up, and because the inside of an iPhone is tightly packed, that pressure pushes the screen or back outwards.

Swelling usually builds slowly over weeks, which is why it's easy to miss until the screen visibly lifts. Older batteries, phones that are often hot, and phones that have been bent or crushed are the most likely to swell.

Warning signs

The screen is lifting or separating from the frame.
There's a visible gap along one edge.
The phone rocks when it's lying flat on a table.
The back is bulging.
Touch is unreliable in one area, or the screen has new marks from pressure.
The phone feels unusually hot while charging.

Safety steps right now

Unplug it and stop charging it.
If it still works, back it up to iCloud, then turn it off.
Keep it somewhere cool, on a hard surface away from anything flammable. Not in a pocket or bag.
Don't press the screen back into place, and don't bend or puncture the phone.
If it's hissing, smoking or getting hot, don't touch it. Keep people away and, if it's safe to do so, move away from it.

Why you shouldn't remove it yourself

Prying out a swollen battery with tools risks puncturing it, and a punctured lithium battery can catch fire. Technicians remove swollen batteries with the right tools and a safe workspace.

The old battery also needs to be disposed of properly. Lithium batteries shouldn't go in household trash. A repair shop recycles them safely as part of the replacement.

Bring it in rather than mailing it

Damaged and swollen lithium batteries have strict shipping restrictions, so a swollen iPhone shouldn't go in the mail without talking to us first. If there's a store near you, bringing it in is the safest option. Find a repair store near you.

When you carry it in, keep it in a hard case or a small box on its own, not loose in a pocket or bag with keys and other metal objects.

Preventing it next time

Keep your iPhone out of heat: car dashboards, direct sun, and charging under pillows or blankets.
Use good-quality, certified chargers and cables.
Turn on Optimized Battery Charging, or the 80% limit on iPhone 15 and later.
Replace the battery once battery health drops below about 80%, rather than running it into the ground.
Don't keep using a phone that's been bent or crushed. Physical damage to the battery can cause swelling later.

How it's fixed

A battery replacement starts at $49.99. Once the swollen battery is out, the screen often sits flat again. If the pressure cracked or damaged the display, it may need a screen repair too. We'll tell you before any work. To understand battery wear, see iPhone battery health, explained.