New lithium battery suppresses fire with built-in safety system

Researchers at the Institute of Chemistry, Chinese Academy of Sciences have developed a lithium metal battery prototype with a built-in flame suppressant to address the fire risks associated with lithium metal batteries. These batteries offer significantly higher energy storage—up to ten times that of conventional lithium-ion cells—making them attractive for electric vehicles and portable electronics. However, their lithium metal anodes and nickel-rich oxide cathodes can generate flammable gases that may cause overheating and explosions. The new design incorporates a polymer into the cathode that remains stable under normal conditions but releases fire-inhibiting radicals when temperatures exceed 100 °C, suppressing the chemical reactions that produce flammable gases. Testing showed that while a standard lithium metal battery overheated to 1,000 °C and ignited within 13 minutes at elevated temperatures, the prototype only reached 220 °C and did not catch fire or explode. This smart flame-retardant system enhances both thermal safety and electrochemical stability, potentially transforming lithium metal batteries into safer options