A swollen phone battery is one of the few phone faults you really shouldn’t put off. If your screen has started lifting at one edge, the back of your phone looks bulged, or the phone rocks when you lay it on a table, the battery inside is probably swelling. It might look like a small cosmetic problem, but it’s a sign the battery has failed inside and a failed lithium-ion battery needs careful handling.
In this guide, the repair team at Gadgets n Repair in St Helens explains what’s actually happening inside the phone, how to recognise the warning signs early, exactly what to do the moment you notice them, and how to get rid of the old battery safely.
Is a swollen phone battery dangerous?
Yes. A swollen battery has been damaged internally, and a damaged lithium-ion battery can overheat or catch fire, so it should be treated as a safety issue, not a cosmetic one.
Inside every phone battery is a liquid electrolyte that lets energy move between the battery’s layers. As the battery ages or gets damaged, that chemistry breaks down and produces gas inside the sealed battery pouch. Because the gas has nowhere to go, the pouch inflates like a small cushion and pushes against whatever is around it, usually your screen or the back panel.
Once a battery has swollen, it’s safest to assume its built-in safety protections can no longer be relied on. That doesn’t mean your phone is about to burst into flames. Most swollen batteries are spotted and replaced without any drama. But the risk goes up if the battery is pressed, punctured, heated or charged, which is why the steps below matter.
How can you tell if your phone battery is swollen?
The most common sign is the screen lifting away from the frame, often starting at one corner or along one edge. Other signs include a bulging back panel, a phone that rocks or spins when laid flat, and a screen that feels slightly soft or springy when you press near the edges.
Repair specialists at iFixit also point out that pressure from a swelling battery can cause a hazy white patch on the display, because the screen layers are being pushed from behind. Some signs are easy to miss at first, so use this table to check your phone:
| What you notice | What it usually means | How urgent |
|---|---|---|
| Screen lifting at an edge or corner | Battery pushing the display out of the frame | Stop charging and get it checked today |
| Back panel bulging or cracking on its own | Battery pushing the back glass or plastic out | Stop charging and get it checked today |
| Phone rocks or spins when laid flat | Early swelling | Get it checked this week; don’t charge overnight |
| White or hazy patch on the screen | Pressure on the display from behind | Get it checked; the screen may also be affected |
| Battery drains fast and phone gets hot | Worn battery that may start to swell | Book a battery check soon |
| Sweet or chemical smell | Battery releasing gas | Switch off, move it away from anything flammable, get help now |
If you’re not sure, lay the phone face-down on a flat table and gently press each corner. A healthy phone sits completely flat. A phone with a swelling battery will usually rock.
What should you do if your phone battery is swollen?
Switch the phone off and stop charging it straight away. Then get it to a repair shop as soon as you can, without pressing on it, bending it, or trying to squeeze the screen back into place.
Here’s the step-by-step version:
- Turn the phone off. Powering down is the first thing to do once you spot swelling, because it stops the battery working harder than it has to.
- Unplug it and don’t charge it again. Charging a swollen battery puts more stress on a cell that’s already damaged. That includes wireless chargers and power banks.
- Don’t squeeze it. It’s tempting to push the lifted screen back down, but pressing on a swollen battery is exactly what you want to avoid. Take the phone out of any tight case and don’t carry it in a tight pocket.
- Keep it away from water. iFixit warns that lithium can react with water, so don’t try to cool the phone under a tap or in the fridge.
- Put it somewhere safe. Leave it on a hard, non-flammable surface such as a tiled floor or a stone worktop, not on a bed, sofa, carpet or in a drawer full of paper.
- Back up quickly, if you can. If the phone still works and isn’t hot, a quick backup to iCloud or Google is worth doing. Don’t leave it switched on for long to do it.
- Book a battery replacement. The sooner the battery is out, the less chance it has of damaging the screen or anything else.
What makes a phone battery swell?
Most swelling is simply age. A lithium-ion battery goes through hundreds of charge cycles over a few years, and with each one its internal chemistry gradually wears down. Heat, physical damage and poor-quality chargers can speed this up or cause it in a newer phone.
The main causes are:
- Age and heavy use. Phones that are three or four years old, or that are charged several times a day, are the most likely to be affected.
- Heat. Leaving a phone in a hot car, in direct sunlight, or charging it under a pillow all put extra strain on the battery.
- Physical damage. Apple’s own safety guidance says a phone battery can be damaged if it’s dropped, crushed, punctured or exposed to liquid. A battery can be damaged in a fall even when the outside of the phone looks fine.
- Damaged or poor-quality chargers. Apple also warns that using damaged cables or chargers can cause fire or damage. Frayed cables and very cheap plugs are worth replacing.
Can a swollen battery be fixed, or do you need a new phone?
The battery itself can’t be repaired: once a lithium battery has swollen, it has to be replaced. The good news is that in most cases only the battery needs replacing, not the whole phone.
When a battery is replaced, a technician carefully opens the phone, removes the swollen battery without puncturing it, fits a new battery and tests the phone before handing it back. If the swelling has pushed the screen out far enough to crack it, bend the frame or leave marks on the display, the screen may need replacing as well.
Whether it’s worth repairing depends on your phone. For most phones from the last few years, a new battery is far cheaper than a new handset and gives the phone a new lease of life. For a very old phone, or one with other faults, it may be better to put that money towards a replacement. A good repair shop will tell you honestly which makes more sense.
One more thing: check your warranty first. If your phone is still under the manufacturer’s warranty, an insurance policy or a care plan, contact them before paying for a repair, a swollen battery may be covered.
Should you remove a swollen battery yourself?
No. Modern phone batteries are glued in place, and prying out a swollen one with the wrong tools risks puncturing it, which is the moment a damaged battery is most likely to catch fire.
Apple’s advice to iPhone owners is direct: don’t attempt to replace the battery yourself. Repair technicians use plastic tools, controlled heat to soften the adhesive and a fire-safe workspace for a reason. If the battery is badly swollen, bring the whole phone in rather than trying to remove anything first.
How do you dispose of a swollen battery in St Helens?
Never put a phone battery, swollen or not, in your household rubbish or recycling bin. Take it to a household waste recycling centre, or let the repair shop dispose of it when they replace it.
Batteries in household waste are a growing fire risk. Research by Material Focus found that over 700 fires in bin lorries and recycling centres were caused by batteries left inside electricals, because they get crushed in the collection process. Across Merseyside and Halton, there are 16 household waste recycling centres that accept batteries.
A swollen battery is damaged, so it’s worth phoning the recycling centre before you go to check how they want it handed over. Carry it in a small box on its own, not loose in a bag with other items. When we replace a battery at Gadgets n Repair, we dispose of the old one for you.
How can you stop your next battery swelling?
Keep your phone cool, use a good-quality charger and cable, and replace the battery when it’s clearly worn rather than waiting for it to swell. Heat is the biggest cause you can control.
- Avoid heat. Don’t leave your phone in a hot car or in direct sun, heat is hard on lithium-ion batteries.
- Charge with airflow. Apple advises keeping your phone and charger in a well-ventilated area while charging, so avoid charging under pillows, duvets or in a bag.
- Look after your cables. Replace frayed cables and damaged plugs straight away, and avoid very cheap unbranded chargers.
- Check battery health. On an iPhone, go to Settings → Battery → Battery Health. On many Android phones, the battery section of Settings or the manufacturer’s support app shows battery condition. If your phone dies early in the day or gets warm doing simple things, get the battery checked before it starts to swell.
- Don’t ignore a fall. If you drop your phone hard and it starts getting hot or draining quickly afterwards, have the battery looked at.
Frequently asked questions
Is a swollen battery still dangerous if the phone is switched off?
Switching the phone off and unplugging it lowers the risk, but it doesn’t make a damaged battery safe. Keep it on a hard surface away from anything flammable and get the battery replaced as soon as you can.
Can I keep using my phone until I have time to get it fixed?
It’s not a good idea. Every time you use or charge it, the damaged battery is put under more strain, and the swelling can get worse and crack the screen.
Will I lose my photos and data when the battery is replaced?
A battery replacement doesn’t normally wipe your phone. Back up anyway if the phone still turns on and isn’t hot, just in case.
Can I post my phone for a mail-in repair?
It’s best not to. You shouldn’t travel unnecessarily with a device that has a bulging battery, and the same applies to sending one through the post, so if you’re local, bring it into the shop.
Do tablets and laptops get swollen batteries too?
Yes. iPads, tablets and laptops use the same type of lithium-ion battery and can swell in the same way. The signs are similar: a lifting screen, a bulging case or a trackpad that no longer clicks properly. Follow the same safety steps and bring the device in.
How much does a swollen battery replacement cost at Gadgets n Repair St Helens?
It depends on your phone’s make and model, and whether the screen has been damaged too. Call us with your model and we’ll give you a price before any work starts.
Swollen battery replacement in St Helens at Gadgets n Repair
If you think your phone battery is swollen, switch it off, stop charging it and bring it in. We’ll check it, tell you honestly whether it’s just the battery or the screen too, and give you a price before we do any work. We’ll also dispose of the old battery safely.
