Japan Develops Fire-proof EV Battery To Boost Safety, Energy Density And More

A groundbreaking innovation from Japan may redefine the future of lithium-ion batteries (LIBs). Researchers from Doshisha University and TDK Corporation have developed a quasi-solid-state LIB that boasts non-flammability, enhanced stability, and high energy density.

The quasi-solid-state LIB blends liquid and solid electrolytes to mitigate traditional battery drawbacks. Conventional designs often struggle to balance energy density with safety and durability, but this novel approach overcomes those challenges. “The improved safety and charge/discharge performance demonstrated the feasibility of quasi-solid-state batteries as a near-future technology,” the research team emphasized in their study.

The battery design incorporates advanced materials, including a silicon (Si) negative electrode and a LiNi0.8Co0.1Mn0.1O2 (NCM811) positive electrode. These materials, regarded as next-generation standards, are separated by a solid lithium-ion conducting glass-ceramic sheet (LICGCTM) from OHARA, enhancing structural integrity.

To optimize compatibility and performance, researchers formulated nearly saturated, non-flammable electrolyte solutions for each electrode. Tris (2,2,2-trifluoromethyl) phosphate and methyl 2,2,2-trifluoromethyl carbonate were key components, ensuring a stable interface between the solid electrolytes and electrodes.

The resulting quasi-solid-state pouch cells, with a capacity of 30 mAh, exhibited remarkable electrochemical performance, strong thermal stability, and high ionic conductivity. Charge/discharge experiments and advanced thermal stability tests, such as accelerating rate calorimetry (ARC), confirmed minimal heat generation even at temperatures of 150°C, underscoring the battery’s robustness.

Traditional solid-state batteries have been plagued by issues like disrupted interfaces and slow lithium-ion transfer. This quasi-solid-state design addresses those challenges by incorporating elastic polymer electrolytes and non-flammable organic solvents. Innovations like polydimethylsiloxane-based gels and high-concentration lithium salt solutions further enhance performance.

Despite these advancements, challenges such as lithium-ion transfer resistance and interface degradation persist. However, optimizing solvation structures and combining electrolytes offer a pathway toward more stable and efficient battery systems.

The new LIB has significant implications for electric vehicles, drones, and cordless appliances, potentially boosting energy efficiency and safety across industries. According to the research team, “Its widespread application can not only improve user convenience but also promote sustainable economic growth.”

The study related to this innovation is published in the Journal of Energy Storage, addressing the limitations of conventional batteries and opening doors to a more sustainable and efficient future for energy storage solutions.