A customized strategy to design intercalation-type Li-free cathodes for all-solid-state batteries. Issue 3 (10th January 2023)

• Record Type: Journal Article
• Authors: Wang, Da; Yu, Jia; Yin, Xiaobin; Shao, Sen; Li, Qianqian; Wang, Yanchao; Avdeev, Maxim; Chen, Liquan; Shi, Siqi
• Is Part Of: National science review. Volume 10:Issue 3(2023)
• Publication Date: 2023-01-10
• Subjects: intercalation-type Li-free cathodes -- all-solid-state Li-metal batteries -- energy density -- p-type alloying strategy -- ligand-field descriptors; Science -- Periodicals; 505
• DOI: 10.1093/nsr/nwad010
• Languages: English
• ISSNs: 2095-5138

Abstract

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-V1.75 Cr0.25 S4 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-V1.75 Cr0.25 S4 . This strategy is not limited to specific Li-free cathodes and offers a solution to achieve high voltage and phase stability simultaneously. Abstract : A critical voltage-tuning/phase-stability competition balance of Li-free cathodes for all-solid-state Li-metal batteries is achieved by the customized p-type alloying strategy, and a conceptual 2H-V1.75 Cr0.25 S4 cathode with record initial-voltage and energy density in intercalation-type Li-free cathode field is designed.