A battery that shuts down at high temperatures

Stanford researchers have invented a lithium-ion battery that shuts down before overheating to prevent the battery fires that have plagued laptops, hoverboards and other electronic devices. The battery restarts immediately when the temperature cools.

The design is an enhancement of a wearable sensor that monitors human body temperature invented by Zhenan Bao, a professor of chemical engineering at Stanford. The sensor is made of a plastic material embedded with tiny particles of nickel with nanoscale spikes protruding from their surface. For the battery experiment, the researchers coated the spiky nickel particles with graphene, an atom-thick layer of carbon, and embedded the particles in a thin film of elastic polyethylene.