Insights on the fundamental lithium storage behavior of all-solid-state lithium batteries containing the LiNi0.8Co0.15Al0.05O2 cathode and sulfide electrolyte

An insightful study on the fundamental lithium storage behavior of all-solid-state lithium battery with a structure of LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA)/Li 10 GeP 2 S 12 /Li-In is carried out in this work. The relationship between electrochemical performances and particle size, surface impurities and defects of the NCA positive material is systematically investigated. It is found that a ball-milling technique can decrease the particle size and remove surface impurities of the NCA cathode while also give rise to surface defects which could be recovered by a post-annealing process. The results indicate that the interfacial resistance between the NCA and Li 10 GeP 2 S 12 is obviously decreased during the ball-milling followed by a post-annealing. Consequently, the discharge capacity of NCA in the NCA/Li 10 GeP 2 S 12 /Li-In solid-state battery is significantly enhanced, which exhibits a discharge capacity of 146 mAh g −1 at 25 °C.