LEE, KYU JOON Byeon, Young Woon Lee, HyunJeong LEE, YEBIN Park, Soo hyung Kim, Hae Ryoung Kim, Hong-Kyu Oh, Soong Ju Ahn, Jae Pyoung 2024-01-12T02:31:40Z 2024-01-12T02:31:40Z 2023-01-20 2023-03 2405-8297 https://pubs.kist.re.kr/handle/201004/75778 Understanding the interfacial phenomena in composite cathodes is essential for achieving excellent cycle performance in all-solid-state batteries (ASSBs), which exhibit high safety performance and energy densities. Herein, we report on the spontaneous crack-healing mechanism in a composite cathode consisting of LiNi0.7Co0.15Mn0.15O2 (NCM) and Li6PS5Cl0.5Br0.5. This cathode exhibited excellent cycle performance during cell tests owing to the stack pressure, which enhanced the ionic and electrical transfers at the material interfaces by remarkably reducing macrocracks between the materials in the composite cathode. Apart from the mechanical effects, a cathode electrolyte interface (CEI) composed of carbon, sulfur, bromine, and oxygen was formed at the interface of NCM and the binder, as decomposing the SSE adjacent to the NCM particles during electrochemical cycles. By contrast, the migration of sulfur and carbon species filled the microcracks between the NCM primary particles inside the secondary particles, thus improving the crucial crack issue of ASSBs. Furthermore, sufficient stack pressure and binding materials played a key role in maintaining the conductive pathway of the cathode by contributing to mechanical crack healing and chemical CEI formation. In this manner, achieving a better understanding of the healing behavior of microcracks and macrocracks in composite cathodes can facilitate the development of ASSBs with a long cycle performance. English Elsevier BV Revealing crack-healing mechanism of NCM composite cathode for sustainable cyclability of sulfide-based solid-state batteries Article 10.1016/j.ensm.2023.01.012 1 Energy Storage Materials, v.57, pp.326 - 333 Energy Storage Materials 57 326 333 Y scie scopus 000991613900001 Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Science & Technology - Other Topics Materials Science Article HIGH-ENERGY DENSITY ELECTROLYTE REDOX DEGRADATION STABILITY All-solid-state battery solid-state electrolyte cycle performance composite cathode crack healing mechanism