Understanding the roles of atomic layer deposition in improving the electrochemical performance of lithium-ion batteries

Rechargeable lithium-ion batteries have been widely used as energy storage devices in electric vehicles and other smart devices due to their excellent properties, such as high energy and power densities, long-term service life, and acceptable cost. The electrochemical performance of the materials in a lithium-ion battery system determines the performance of the battery, so it is essential that the electrochemical properties of these materials be improved. Atomic layer deposition is a versatile thin film coating technique for surface functionalization that can deposit a highly uniform thin film of nanoscale thickness on battery components, and it has been proven to improve the electrochemical performance of materials that operate in a lithium-ion battery system, such as rate capability, interface stability, and cycling life. This review paper focuses on recent advances of application of atomic layer deposition in lithium-ion batteries and summarizes the roles of such thin film coatings in improving the electrochemical performance of batteries. The present review summarizes and classifies the latest understanding of improvement mechanisms proposed by researchers according to different components in lithium-ion batteries, including cathodes, anodes, separators, and solid electrolytes. This review will not only help researchers in this field to comprehend the roles of atomic layer deposition thin film coating for improving the performance of various components in a battery system, but will also help them choose appropriate coating materials on battery components. In addition, we briefly discuss the limitations of atomic layer deposition in lithium-ion battery applications and the challenges that it faces in the future.