New tech to prevent Li-ion battery fires

Materials scientists from Nanyang Technological University Singapore have found a way to prevent internal short-circuits, the main cause of fires in Li-ion batteries.

Billions of Li-ion batteries are produced annually for use in mobile phones, laptops, personal mobile devices, and the huge battery packs of electric vehicles and aircraft.

This global battery demand is set to grow, with electric vehicles alone requiring up to 2,700 GWh worth of Li-ion batteries a year by 2030, equivalent to some 225 billion mobile phone batteries.

Even with an estimated failure rate of less than one-in-a-million, in 2020 there were 26 power-assisted bicycle (PAB) fires and 42 cases of personal mobility device fires in Singapore.

In most Li-ion battery fires, the cause is due to a build-up of lithium deposits known as dendrites (tiny wire-like tendrils) that cross the separator between the positive (cathode) and negative (anode) electrodes of the battery when it is being charged, causing a short-circuit leading to an uncontrolled chemical fire.

To prevent such battery fires, NTU scientists invented a patent-pending “anti-short layer” that can be easily added inside a Li-ion battery, preventing any future short-circuits from occurring during the charging process.

This concept is akin to adding a slice of cheese to a hamburger’s meat patty in between the buns, thus the new “anti-short layer” can be rapidly adopted in current battery manufacturing.