Built-in fire extinguishers can prevent battery explosions

A groundbreaking advancement in battery technology has been achieved with the development of batteries enhanced with a polymer material that releases fire-suppressing chemicals at high temperatures. This innovative technique significantly reduces the risk of battery explosions and fires, thereby enhancing the safety of battery-reliant devices such as electric cars and medical equipment.

Lead researcher, Ying Zhang, from the Institute of Chemistry at the Chinese Academy of Sciences, explains, “Our approach enhances safety within mainstream liquid lithium batteries by acting as a safety valve that releases chemicals to suppress flammable gases and prevent explosions, effectively preventing fires.”

Zhang and her team conducted experiments on a prototype lithium metal battery containing the flame-retardant polymer material. While current lithium metal batteries are not widely used, the next-generation versions hold promise for replacing conventional lithium-ion batteries in electric vehicles and portable electronics due to their ability to store significantly more energy. The researchers subjected both the prototype battery and a standard lithium metal battery to increasing temperatures, starting from 50°C. When the external temperature exceeded 100°C, both batteries experienced overheating, but the prototype’s polymer material began to break down, releasing chemicals that acted as “microscopic fire extinguishers,” according to Zhang.

At temperatures above 120°C, the standard battery without safety features overheated rapidly, reaching 1000°C within 13 minutes and igniting. In contrast, the prototype battery equipped with the special polymer material only reached a peak temperature of 220°C under the same conditions, without catching fire or exploding.

This groundbreaking material science approach not only reduces the risk of battery fires in lithium metal batteries but also shows potential for enhancing safety in lithium-ion and lithium-sulfur batteries, says Jagjit Nanda from the SLAC National Accelerator Laboratory in California. The implementation of this fire-suppressing technology could lead to safer batteries, particularly for electric vehicles and possibly electric aircraft.

Zhang emphasizes that incorporating this technology into existing battery manufacturing processes could serve as a near-term safety enhancement while the industry explores long-term solutions involving alternative battery designs and chemistries. However, the integration of the polymer material into batteries would require some adjustments to manufacturing processes, she notes.