A high-entropy mixed ionic and electronic conductor for accelerating the cathode dynamics in all solid–state lithium metal batteries
- Xiangkun Kong
- Zongzi Jin
- Linwang Chen
- Xianzhun Huang
- Bingzi Feng
- Huang Huang
- Yifan Xu
- Weihao Wu
- Wenkan Yang
- Shiji Shen
- Zhiwen Zhuo
- Weiwei Ping
- Ranran Peng
- Chusheng Chen
- Chengwei Wang
2025-11-12
Both electron and ion transports determine the dynamics of the cathode in all solid–state lithium metal batteries (ASSLMBs). Traditional composite strategies combining solid electrolytes and electronic conductors cause complex solid-state interfaces that hinder carrier migration. We present a high-entropy mixed ionic and electronic conductor (HE-O-MIEC), Li 1/6-x (LaPrNdSrBa) 1/6 CoO 3-δ , based on oxidation-resistant electronic conductors. HE-O-MIEC exhibits an electronic conductivity of 1150 siemens per centimeter and a Li + conductivity of 2.3 × 10 −4 siemens per centimeter at room temperature. The enhanced Li + conductivity is attributed to the large configurational entropy, promoting multicomponent solubility and increased Li + concentration. HE-O-MIEC exhibits electrochemical and thermodynamic compatibility with LiCoO 2 and stabilizes ion/electron transport in the ASSLMB using the Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 electrolyte. Without organic electrolyte or additional pressure, the ASSLMB achieves 115–milliampere·hours per gram initial discharge capacity at 30°C and retains 83% capacity after 500 cycles. Homogeneous electron and ion transport in the HE-O-MIEC demonstrates potential to improve active material utilization and address interfacial challenges in ceramic-based ASSLMBs.