Do you have any devices that contain lithium batteries? The chances are that you do. Lithium ion batteries are very common in the technology industry and are used in cameras, watches and smartphones, so it’s very likely that you come into contact with them on a daily, if not hourly, basis.
However, they are also known for being hazardous and in the most extreme cases, explosive. One frequently reported example is the Samsung Galaxy Note 7: there have been 35 confirmed cases of the battery catching fire. Yet, in defence of the lithium battery, only 1 in 10 million lithium-ion batteries are likely to malfunction. In fact, you are more likely to die in a car crash (a 1 in 10,000 chance ) than get injured by a malfunctioning ion battery.
It was reported just last week that a woman who was wearing headphones powered by lithium batteries was injured when travelling on a flight from Beijing to Melbourne. As she was listening to music, her headphones started sparking and caught fire. She was left with a blackened face and blisters on her hand.
But why do lithium batteries explode? A lithium-ion battery is made up of power-generating compartments called cells. The cells are made of three components which are a positive electrode, made of lithium-cobalt oxide; a negative electrode, which is made of carbon; and a chemical called an electrolyte. As the battery is charging up, the positive electrode gives up some of its lithium ions. This moves through the electrolyte to the negative electrode, where it stays. The battery takes the energy in and stores it during this process. When the battery is not charging, the lithium ions move back to the positive electrode from the negative. This produces the energy that powers the battery.
Problems occur when the batteries are charged too quickly. This can create lots of heat and, eventually, a fire. Lithium batteries have built in electronic controllers which control the speed of charging to try to prevent this problem – but clearly this is not always effective.
Several students at Colchester County High for Girls said they were worried that their phone or charger could explode. Gimhani, 14, said, “My parents always tell me not to leave my phone charging for too long as it might catch fire”. Bridget, 14, said, “If my phone overheats, then there is a small chance that it will explode.”
Whether or not you decide lithium batteries are too dangerous for use, it would be hard to stop using them. Lithium batteries are in all types of phones, not just Samsungs. But students should be reassured that, while there is a small chance that their phone battery could catch fire, it is extremely unlikely.