The problem of the explosiveness of mobile devices has become most acute only in the last few years. "Explosion" is a rather dramatic term to describe all those incidents that happened to smartphones from Samsung and Apple. Spontaneous combustion of smartphones of these particular manufacturers is well-known, but phones of any brands and models are at risk.
Any mobile device draws energy from the battery, which is also the main cause of danger. Modern smartphones use lithium-ion batteries as batteries, and they contain flammable materials. Any damage, even minor damage, can trigger a chemical reaction that will either swell or ignite the battery.
Chemically, the battery consists of cathodes and anodes, separated by a membrane. If these two elements react with each other, a sharp release of heat will occur and the gadget's battery will begin to swell. In order for an explosion to occur in its broadest sense, an already started chemical process needs access to air.
The main reason for battery failure and its probable explosion hazard is the use of non-original chargers. In most of the known cases, smartphone ignition occurred during the charging process using a universal charger. Unfortunately, it is not possible to determine in advance if the battery is damaged and thus to be on the safe side.
The most important thing is not to worry too much, there are only a few dozen officially confirmed cases of smartphone explosions.
