Zero ''dead-weight'' composite cathode application in all-solid-state Li-metal batteries with industrial relevant areal capacities Qi Xu1; Shicheng Yu2; Anna Windmüller3; Hermann Tempel3; Shibabrata Basak3; Hans Kungl3; Rüdiger-a. Eichel3; 1RESEARCH CENTER JUELICH, Jülich, Germany; 2RESEARCH CENTER JüLICH, Jülich, Germany; 3RESEARCH CENTER JüLICH, Juelich, Germany; PAPER: 367/AdvancedMaterials/Regular (Oral) SCHEDULED: 14:50/Tue. 29 Nov. 2022/Saitong ABSTRACT: In the composite cathode of all-solid-state Li-metal batteries (ASSBs), the high interfacial resistance and unstable interphase between the cathode active material (CAM) and solid-state electrolyte (SSE) are two of the main reasons for the low energy density in current ASSBs [1] . Matching the physical/(electro)chemical properties of the CAM and SSE is vital to obtaining a stable interface/interphase in the composite cathode [2]. Li<sub>1.3</sub>Al<sub>0.3</sub>Ti<sub>1.7</sub>(PO<sub>4</sub>)<sub>3</sub> (LATP) is a promising candidate as a Li<sup>+</sup> conductive component in all-phosphate-based composite cathode produced by a co-firing method due to its good thermal chemical stability against phosphate-based CAMs [3]. Herein, with the effort to optimize the synthesizing and sintering process of LATP, highly-conductive LATP is obtained at a low sintering temperature [4]. Consequently, the phosphate-based CAM/LATP interface in composite cathode is stabilized, which significantly improves the energy density of ASSBs. Specifically, a high-density, fully phosphate-based composite cathode is prepared by co-firing LiFePO<sub>4</sub> (LFP) and (LATP). In this way, an ion-conductive and redox-active Li<sub>3-xFe2-x-y</sub>Ti<sub>x</sub>Al<sub>y</sub>(PO<sub>4</sub>)<sub>3</sub> (LFTAP) interphase is formed at the interface between LFP and LATP after heating, which not only improves the adhesion of materials but also provides additional capacity. The structure of the fabricated composite cathode is studied in detail. The electrochemical performance and the influence of the electrochemically active LFTAP interphase and LATP solid-electrolyte of the corresponding ASSBs composed of the co-fired LFP/LATP composite cathodes are investigated. References: [1] C. Yu, S. Ganapathy, E. R. H. V. Eck, H. Wang, S. Basak, Z. Li, M. Wagemaker, Nat. Commun. 2017, 8, 1086. [2] S. Yu, A. Mertens, H. Tempel, R. Schierholz, H. Kungl, R. A. Eichel, ACS Appl. Mater. Interfaces 2018, 10, 22264. [3] M. Gellert, E. Dashjav, D. Grüner, Q. Ma, F. Tietz, Ionics (Kiel). 2018, 24, 1001. [4] Q. Xu, C. L. Tsai, D. Song, S. Basak, H. Kungl, H. Tempel, F. Hausen, S. Yu, R. A. Eichel, J. Power Sources 2021, 492, 229631. |