Thermal runaway is a phenomenon that affects lithium-ion batteries, which power so many of the devices that people use every day, such as mobile phones, tablets, laptops, electric bikes, scooters, cars, and hoverboards.

Lithium-ion batteries can store a lot of power in a small space. That energy density is one of the reasons why lithium-ion chemistry is so commonly used for powering portable devices. But it comes with a trade-off: the risk of thermal runaway.