Advances in Lithium Metal Batteries for Longer-Lasting Electric Vehicles
The adoption of electric vehicles is causing a rise in demand for next-generation secondary batteries with higher capacity and faster charging than today’s lithium-ion batteries. Lithium metal batteries are promising as rechargeable batteries as the lithium metal anode exhibits a theoretical capacity 10x higher than commercial graphite anode. However, lithium dendrites grow on the anode during charging-discharging, resulting in poor battery performance and short circuits.
Researchers at the Carbon Composite Materials Research Center of the KIST Jeonbuk Institute of Advanced Composition Materials and the Institute of Science and Technology (GIST) developed a technology to improve battery durability using carbon fiber paper as the anode material for lithium metal batteries.
The research team replaced lithium metal-coated copper thin film with a thin carbon fiber paper containing lithium metal. Carbon fiber paper has a hierarchical structure on the carbon monofilament made of amorphous carbon and inorganic nanoparticles. It enhances lithium affinity and prevents the growth of lithium dendrite. Copper thin film anode short-circuits after approximately 100 cycles; the carbon fiber paper anode exhibits cycling stability for 300 cycles. It also shows a high energy density of 428 Wh/kg, about 1.8x higher than copper thin film (240 Wh/kg).
Dr. Sung-Ho Lee, Head of the Center at KIST, who led the research, said, “Considering the 5x lower density and lower cost of carbon fiber compared to copper, our proposed anode material is an important achievement that can accelerate the commercialization of durable and lightweight lithium metal batteries.”