High cathode utilization efficiency through interface engineering in all-solid-state lithium-metal batteries†
All-solid-state batteries based on inflammable inorganic solid electrolytes can fundamentally solve safety issues, especially for high-energy-density Li-metal anodes. However, the development of all-solid-state Li-metal batteries based on a high-capacity lithium layered oxide material is still hindered by the low utilization efficiency of the cathode. Herein, with interface engineering, LiNi0.6Mn0.2Co0.2O2 micro-sized crystalline grains were introduced to make a composite cathode with interfacial stability, continuous Li+ transport channels, and reduced grain interfaces to improve the utilization efficiency. The solid batteries based on the micro-sized crystalline grain material showed initial charge capacity up to ∼170 mA h g−1, discharge capacity of ∼140 mA h g−1, good rate performances, and outstanding cycling stability. The high utilization efficiency of the cathode highlights a promising choice for constructing a composite cathode by micro-sized crystalline grain materials and shines light on the future application of higher-energy-density layered oxide cathode materials.