Fire in the Pocket: Why Smartphones Catch Fire and How to Avoid Danger

The Ministry of Emergency Situations informs  A modern smartphone is no longer just a phone, but a whole mini-computer packed with technologies. We carry it with us everywhere: to work, to the gym, to bed, on the plane. It contains a processor, memory, a display, numerous microchips, and of course, a battery. And the battery is a chemical component. Inside it, complex processes occur, and if something is wrong with it, the consequences can be, to put it mildly, unpleasant. Swelling, smoke, crackling, and sometimes even ignition — all these are real cases that happen more often than one would like.

Recently, in one of the Moscow schools, a noteworthy incident occurred: a boy decided to test the strength of his smartphone and tried to bend it. As a result, the device caught fire right in his hands, and the room quickly filled with smoke.

A little later, another story emerged, which again reminded us that batteries are no joke. Flight Air China CA139, which took off from Hangzhou to Incheon (South Korea), had to make an emergency landing in Shanghai. The reason is banal and terrifying at the same time — a battery caught fire in the luggage: apparently, someone had tightly squeezed an external battery with the luggage compartment door. Passengers filmed everything: thick smoke, alarm, panic. I think many felt uneasy, as such a situation can happen literally to anyone.

Fortunately, nobody was hurt, but these stories clearly show how dangerous it is to handle technology without understanding that inside is not just metal, but a chemical battery.

Today's batteries are quite reliable. Technologies have advanced significantly, and in general, modern smartphones can withstand impact. With normal use, the phone will not let you down — it will not explode or catch fire just like that. The other thing is that many continue to use gadgets that have long been asking for retirement: a cracked case, a swollen cover, a battery barely holding on, but a person stubbornly charges it three times a day and sees no problem. However, a battery is a consumable item; it can and should be replaced, just like tires on a car or a filter in a vacuum cleaner.

Why a battery may swell, smoke, or catch fire

Batteries in modern gadgets are mainly lithium-ion or lithium-polymer. They are compact, energy-dense, and quite sensitive to external influences. When they are overheated, damaged, or charged with poor-quality devices, they can literally "lose their temper".

One of the most common reasons is overheating. Imagine: a smartphone is constantly in the sun, lying in a car under direct rays, or charging under a pillow. Inside the battery, a reaction begins — pressure rises, the electrolyte boils, and the case can swell. If not noticed in time, it can end in tragedy — even ignition.

The second reason is mechanical damage. You drop the phone, the case seems intact, but inside the battery has received a micro-crack. The electrodes may touch, a short circuit will occur — and then everything follows the script: heating, smoke, flame.

The third is the use of non-original or defective chargers. When the charger supplies unstable voltage, the battery may overcharge or, on the contrary, discharge quickly, which severely wears out the cells. Over time, they lose stability, and again — hello, overheating and swelling.

Another reason is aging. Even if you handle the smartphone carefully, a lithium-ion battery loses capacity over time. As the cells age, they hold charge worse and heat up more. Sometimes gases form inside, which lead to that very "swollen battery" effect.

And, of course, factory defects. No one is immune to manufacturing defects.

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