Lithium-ion batteries are in everything from cell phones to cars. However, recent incidents involving fires or explosions of these devices show there’s a need for safer batteries. One option is to replace the flammable liquid electrolyte with a solid-state electrolyte (SSE). But some of the most-studied SSEs are themselves flammable, leaving the original safety concern unaddressed. Researchers now report in ACS’ Nano Letters that they have developed an SSE that won’t burn up.
Traditional lithium-ion batteries consist of a cathode and anode, separated by a liquid electrolyte and a thin piece of porous plastic. If the battery is damaged — for example, if it is overcharged or if needlelike lithium projections grow and pierce the plastic separator — the electrolyte can catch fire. Scientists have experimented with a variety of solutions, such as adding fire retardants to the electrolyte, or replacing the soft and flammable separator and electrolyte with an SSE.