Atomic Layer Deposition for Thin Film Solid-State Battery and Capacitor

The demand for electrical power management has increased in recent years, owing partly to increasing contribution of intermittent renewable energy resources to the overall electricity generation. Electrical energy storage systems, such as batteries and capacitors, are core technologies for effective power management. Recent significant technological developments for these energy storage devices include the use of thin film components, which result in increased capacity and reliability. Specifically, thin films with high integrity and uniformity are required in the electrolytes of solid-state Li batteries (SSLBs) and the dielectrics of electrostatic capacitors (ECs), even at extremely thin length scale (< 100 nm) and on complex nanostructures. In this regard, atomic layer deposition (ALD), which can deposit uniform and dense thin films over 3-dimensional (3D) structures, has demonstrated its efficiency in increasing device performance, particularly when applied to the electrolytes and dielectrics of SSLBs and ECs. As a result, the applications of ALD techniques to SSLB electrolytes and EC dielectrics will be examined in this study, with a particular emphasis on research instances that used high aspect ratio structures with conformal ALD coating. Finally, we will discuss how recent advances in innovative ALD processes and equipment with better controllability, versatility, throughput, and economy may further contribute to the development of SSLBs and ECs, especially at scaled-up level.