On-surface lithium donor reaction enables decarbonated lithium garnets and compatible interfaces within cathodes

Ya-Nan Yang; Ying-Xiang Li; Yi-Qiu Li; Tao Zhang

doi:10.1038/s41467-020-19417-1

On-surface lithium donor reaction enables decarbonated lithium garnets and compatible interfaces within cathodes

Nat Commun. 2020 Nov 2;11(1):5519. doi: 10.1038/s41467-020-19417-1.

Authors

Ya-Nan Yang^{1

2}, Ying-Xiang Li^{1

2}, Yi-Qiu Li¹, Tao Zhang^{3

4}

Affiliations

¹ State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai, 200050, P.R. China.
² Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China.
³ State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai, 200050, P.R. China. taozhang@mail.sic.ac.cn.
⁴ Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China. taozhang@mail.sic.ac.cn.

Abstract

Lithium garnets have been widely studied as promising electrolytes that could enable the next-generation all-solid-state lithium batteries. However, upon exposure to atmospheric moisture and carbon dioxide, insulating lithium carbonate forms on the surface and deteriorates the interfaces within electrodes. Here, we report a scalable solid sintering method, defined by lithium donor reaction that allows for complete decarbonation of Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZTO) and yields an active LiCoO₂ layer for each garnet particle. The obtained LiCoO₂ coated garnets composite is stable against air without any Li₂CO₃. Once working in a solid-state lithium battery, the LiCoO₂-LLZTO@LiCoO₂ composite cathode maintains 81% of the initial capacity after 180 cycles at 0.1 C. Eliminating CO₂ evolution above 4.0 V is confirmed experimentally after transforming Li₂CO₃ into LiCoO₂. These results indicate that Li₂CO₃ is no longer an obstacle, but a trigger of the intimate solid-solid interface. This strategy has been extended to develop a series of LLZTO@active layer materials.

Publication types

Research Support, Non-U.S. Gov't