Surface modification of high voltage cathodes can enhance the electrochemical performance of solid-state batteries (SSBs) employing sulfide electrolytes. LiNbO₃-coating is a common method, however, the role and potential of such coating on the high-nickel cathode is still under-discovered especially during extended cycling at different rates in wide temperature ranges. Herein, we carry out in-depth study of LiNbO₃ coating enabled chlorine-rich argyrodite-based SSBs using LiNi_0.7Co_0.1Mn_0.2O₂ (NCM712) cathode at various C-rate (0.1, 0.5, and 1 C) and wide temperatures (-20 °C, 25 °C (RT), and 60 °C). The LNO@NCM712 electrode delivers initial discharge capacities of 80.9 and 138.9 mAh/g at 5 C under RT and 60 °C respectively with better capacity retentions of 87.5% and 88% after 600 and 300 cycles than that of the NCM712 electrode. Moreover, the LNO@NCM712 electrode also shows better electrochemical behavior than the pristine electrode under deep-freezing temperature (-20 °C). The improved battery performance of the LNO@NCM712 electrode is supported by the resistance changes between the cathode and solid electrolyte revealed by EIS and the structural evolution of active materials unraveled by TEM. This study offers a deep insight into the influence of the modification layer for the performance of SSBs and guidance of design strategy for cathode modification.

高压正极的表面改性可以提高采用硫化物电解质的固态电池 (SSB) 的电化学性能。LiNbO ₃涂层是一种常见的方法，然而，这种涂层在高镍正极上的作用和潜力仍未得到充分发现，尤其是在宽温度范围内以不同速率延长循环期间。在此，我们使用 LiNi _0.7 Co _0.1 Mn _0.2 O ₂对 LiNbO ₃涂层启用富氯银铅矿基 SSB进行了深入研究(NCM712) 阴极在各种 C 速率（0.1、0.5 和 1 C）和宽温度（-20 °C、25 °C (RT) 和 60 °C）下。LNO@NCM712 电极在 RT 和 60°C 下 5 C 的初始放电容量分别为 80.9 和 138.9 mAh/g，在 600 和 300 次循环后的容量保持率比 NCM712 电极更好，分别为 87.5% 和 88%。此外，LNO@NCM712 电极在深度冷冻温度（-20°C）下也表现出比原始电极更好的电化学行为。LNO@NCM712 电极电池性能的改善得益于 EIS 揭示的正极和固体电解质之间的电阻变化以及 TEM 揭示的活性材料的结构演变。