Stabilizing Effect of a Hybrid Surface Coating on a Ni-Rich NCM Cathode Material in All-Solid-State Batteries

作者：A‐Young Kim, Florian Strauss, Timo Bartsch, Jun Hao Teo, Toru Hatsukade, Andrey A. Mazilkin, Jürgen Janek, Pascal Hartmann, Torsten Brezesinski · 发表于：Chemistry of Materials · 年份：2019 · DOI：10.1021/acs.chemmater.9b02947 · 被引用次数：266 · 研究领域：Advancements in Battery Materials、Advanced Battery Materials and Technologies、Advanced Battery Technologies Research

Bulk-type all-solid-state batteries (SSBs) are receiving much attention as next-generation energy storage technology with potentially improved safety and higher power and energy densities (over a wider operating temperature range) compared to conventional Li-ion batteries (LIBs). However, practical implementation of SSBs faces a number of hurdles, such as issues related to interfacial stability between the solid electrolyte (SE) and other active and inactive electrode constituents. One approach to effectively prevent or mitigate side reactions at the positive electrode is through surface coating of the cathode material with a dielectric material. In this article, we report on the preparation of Li 2 CO 3 - and Li 2 CO 3 /LiNbO 3 -coated NCM622 (60% Ni) for application in pelletized SSB cells using β-Li 3 PS 4 as the SE. Specifically, we demonstrate that in contrast to state-of-the-art LIBs, the presence of surface carbonate contaminants helps improve the cell cyclability, and the combination of carbonate and niobate species in a kind of hybrid or solid-solution coating is particularly beneficial for achieving stable performance of Ni-rich NCM composite cathodes of practical loading (91% capacity retention after 100 cycles at a C/10 rate and 25 °C). This is in part because of the formation of robust interfaces in the cathode layer, strongly suppressing CO 2 evolution (because of decomposition of the relevant carbonate species) and the accompanied SO 2 formation and release dur...