Yes your laptop computer or mobile phone may explode. There are few instances of deadly explosions also. In 2006 Dell, Apple, Toshiba and Lenovo recalled their laptop batteries from the market. Even user’s laptop batteries were replaced.
Injury due to overheat
In 2002 a fifty year old Swedish scientist burned his penis and testicles. It was because of overheated battery. He was writing a report keeping his laptop on the lap. Laptop manufacturers warn the users not to expose skin directly to laptop. But that scientist was wearing trousers and underpants.
This year (2012) a man in Dhaka was burned to death because of laptop explosion. He was sleeping and he kept his laptop on his bed connecting it to the charger for whole night.
There are also instances of mobile phone explosions.
How these explosions happen?
Lithium ion battery is the culprit. These batteries can store much more energy compared to lead acid battery. This is why today’s manufacturers use lithium ion batteries in electronic products like laptops, mobile phones, cameras and even in electric cars.
Users prefer small and lightweight gadget and they also want a long backup time. So the manufacturers try to make powerful batteries in small size.
Actually lithium ion battery is a pressurized container of lithium containing fluid. This fluid also contains unwanted metal fragments which are very difficult to control. Some techniques are used to minimize the number of fragments. When the batteries are heated due to use or recharging, these metal fragments get more energy to move around. In this situation these fragments may puncture the separator which separates anode and cathode. This can cause short circuit.
The lithium ion containing fluid is a flammable fluid, spark due to short circuit may explode the battery, rising temperature may melt the battery or battery container may explode because of high pressure. Increased temperature may increase the pressure.
Much more sophisticated safety precautions including cooling system, automatic shutdown system are applied for electric car lithium ion batteries.
So do not use your mobile phone while charging,
Ensure ventilation of your laptop; check whether something is there which is preventing air flow.