Progress in the Cycling Performance of Oxidic Solid-State Batteries Fabricated at Room Temperature by Powder Aerosol Deposition

The fabrication of solid-state batteries (SSBs) without the need for high-temperature sintering significantly requires less energy. The powder aerosol deposition (PAD) method enables direct film formation at room temperature, bypassing the conventional thermal densification step. This study presents an overview of recent advancements in the cycling properties of SSBs fabricated via PAD. Employing LiNi$_{0.82}$Mn$_{0.07}$Co$_{0.11}$O$_2$ (NMC) as cathode active material (CAM) and Li$_7$La$_3$Zr$_2$O$_{12}$ (LLZO) as solid electrolyte, a capacity of 141 mAh g$^{−1}$ with 90 % capacity retention over 25 cycles is demonstrated with no thermal post-treatment applied after film fabrication. Based on these results, the role of LLZO as catholyte in the cathode layer is investigated. The findings suggest an electrochemical instability between nickel-rich NMC and LLZO during cycling. To enhance the capacity, the aggregated results are used to discuss various strategies for optimizing cathode layer design, particularly with respect to the composition and choice of the CAM.