A customized strategy to design intercalation-type Li-free cathodes for all-solid-state batteries

Da Wang; Jia Yu; Xiaobin Yin; Sen Shao; Qianqian Li; Yanchao Wang; Maxim Avdeev; Liquan Chen; Siqi Shi

doi:10.1093/nsr/nwad010

A customized strategy to design intercalation-type Li-free cathodes for all-solid-state batteries

Natl Sci Rev. 2023 Jan 10;10(3):nwad010. doi: 10.1093/nsr/nwad010. eCollection 2023 Mar.

Authors

Da Wang^{1

2}, Jia Yu³, Xiaobin Yin¹, Sen Shao⁴, Qianqian Li³, Yanchao Wang⁴, Maxim Avdeev^{5

6}, Liquan Chen⁷, Siqi Shi^{1

3

2}

Affiliations

¹ School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China.
² Zhejiang Laboratory, Hangzhou 311100, China.
³ Materials Genome Institute, Shanghai University, Shanghai 200444, China.
⁴ State Key Laboratory of Superhard Materials & International Center for Computational Method and Software, Jilin University, Changchun 130012, China.
⁵ Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW 2232, Australia.
⁶ School of Chemistry, University of Sydney, Sydney 2006, Australia.
⁷ Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.

Abstract

Pairing Li-free transition-metal-based cathodes (MX) with Li-metal anodes is an emerging trend to overcome the energy-density limitation of current rechargeable Li-ion technology. However, the development of practical Li-free MX cathodes is plagued by the existing notion of low voltage due to the long-term overlooked voltage-tuning/phase-stability competition. Here, we propose a p-type alloying strategy involving three voltage/phase-evolution stages, of which each of the varying trends are quantitated by two improved ligand-field descriptors to balance the above contradiction. Following this, an intercalation-type 2H-V_1.75Cr_0.25S₄ cathode tuned from layered MX₂ family is successfully designed, which possesses an energy density of 554.3 Wh kg^-1 at the electrode level accompanied by interfacial compatibility with sulfide solid-state electrolyte. The proposal of this class of materials is expected to break free from scarce or high-cost transition-metal (e.g. Co and Ni) reliance in current commercial cathodes. Our experiments further confirm the voltage and energy-density gains of 2H-V_1.75Cr_0.25S₄. This strategy is not limited to specific Li-free cathodes and offers a solution to achieve high voltage and phase stability simultaneously.

Keywords: all-solid-state Li-metal batteries; energy density; intercalation-type Li-free cathodes; ligand-field descriptors; p-type alloying strategy.