The phone screen starts separating from the frame. The laptop touchpad clicks by itself or the bottom cover no longer closes properly. These are classic signs of a swollen battery — one of the few faults you shouldn’t put off.
How to recognise a swollen battery
In a phone:
- The screen lifts on one side or there’s a gap between the screen and the frame.
- The back cover separates or has a bulge.
- The phone doesn’t sit flat on the table: it rocks.
- The screen has marks or pressure spots that weren’t there before.
In a laptop:
- The touchpad lifts, is hard to press or clicks by itself.
- The keyboard bulges in one area.
- The bottom cover deforms or doesn’t fit.
- The laptop wobbles on the table.
Why batteries swell
Lithium batteries contain an electrolyte that, over time or in bad conditions, breaks down and produces gas inside the cell. Because the battery is sealed, the gas inflates it. The most common causes:
- Age and charge cycles: natural wear after several years.
- Heat: leaving the device in the sun, in a car or charging on the bed speeds up degradation a lot.
- Always sitting at 100%: very typical in laptops that stay plugged in for months.
- Poor-quality or faulty chargers.
- Impacts that damage the cell internally.
- Low-quality batteries of dubious origin.
Why it’s dangerous
A swollen battery is an internally damaged battery. Besides breaking the screen, touchpad or casing from the inside, it’s more likely to overheat, catch fire or release toxic smoke, especially if punctured, bent or kept charging.
No need to panic, but you should act now.
What to do
- Stop charging it and, if you can, stop using it.
- Turn it off and leave it somewhere cool, on a non-flammable surface and away from anything that could burn.
- Back up your data if the device still works and you can do it quickly, without charging it.
- Get the battery replaced as soon as possible.
What NEVER to do
- Don’t puncture it to “let the air out”. Puncturing a lithium battery can start a fire instantly.
- Don’t squash it or force the cover shut.
- Don’t heat it or put it in the freezer.
- Don’t throw it in the regular bin. Batteries go to a recycling centre or a battery collection point. If we replace it, we take care of recycling it.
How it’s replaced
Replacing a swollen battery takes more care than a normal replacement, because the battery is deformed and usually glued in place:
- The device is opened without pressing on the battery.
- The adhesive is released slowly, without bending it (phones use pull tabs or isopropyl alcohol to soften the glue).
- A new battery is fitted and the other parts (screen, touchpad, connectors) are checked for pressure damage.
In many cases the device works perfectly again with the new battery. If the screen was damaged by the pressure, we’ll tell you in the quote.
How to prevent it
- Avoid heat: don’t charge your phone or laptop in the sun, in the car or on the bed.
- On laptops that are plugged in most of the time, enable the charge limit (many brands include it in their software, usually at 80%).
- On phones, enable optimised charging.
- Use quality chargers and replace the battery when its health drops below 80%. We explain it in when to replace an iPhone battery.
Battery replacement in Carcaixent and La Ribera
At Systemaxo we replace swollen batteries in phones and tablets and laptops in Carcaixent, Alzira, Algemesí, Xàtiva and nearby towns (Valencia). If your battery has swollen, contact us and stop charging it.