上海大学赵玉峰团队的研究发现，高熵O3型阴极中的非均匀配位实现板状滑动抑制和持久的钠储存。相关研究成果发表在2024年10月10日出版的《德国应用化学》。

O3型层状氧化物是钠离子电池（SIBs）非常有前景的阴极，但它们会经历复杂的相变，对空气表现出高灵敏度，导致亚循环性能和商业可行性。

该文中，研究人员报告了一种具有最先进的高熵成分设计的层状阴极材料（NaNi_0.29Cu_0.1Mg_0.05Li_0.05Mn_0.2Ti_0.2Sn_0.11O₂）。研究发现，这种具有过渡金属（TM）元素非均匀配位环境的配置可以在理论和实验上增强TMO₂板在离轴时的滑动能量（-0.38 vs-0.58 eV），这是HEO材料出色结构稳定性的根本原因。

因此，传统O3型阴极的复杂相变（O3-O'3-P3-P'3-P3'-O3'）已被消除，所获得的材料在准固态电池中表现出卓越的结构鲁棒性和完整性，具有超长的循环寿命（在2℃下1000次循环后保持73.2%的容量）。此外，该材料具有令人满意的空气稳定性，直接暴露在空气中时结构和电化学降解最小。研究人员构建了一种基于阴极材料的Ah级袋式电池，在500次循环后显示出83.6%的容量保持率，预示着商业应用的巨大前景。

附：英文原文

Title: Inhomogeneous Coordination in High-entropy O3-type Cathodes Enables Suppressed Slab Gliding and Durable Sodium Storage

Author: Shengyu Zhao, Fanghua Ning, Xuan Yu, Baiyu Guo, Reinaldo F. Te, Jianyu Huang, Qinhao Shi, Shuang Wu, Wuliang Feng, Yufeng Zhao

Issue&Volume: 2024-10-10

Abstract: O3-type layered oxides are highly promising cathodes for sodium-ion batteries (SIBs), however they undergo complex phase transitions and exhibit high sensibility to air, leading to subpar cycling performance and commercial viability. In this work, we report a layered cathode material (NaNi0.29Cu0.1Mg0.05Li0.05Mn0.2Ti0.2Sn0.11O2) with a sate-of-the-art high-entropy compositional design. We unveil that such a configuration featuring inhomogeneous coordination environment of transition metal (TM) elements, can enable enhanced gliding energy (-0.38 vs -0.58 eV) of TMO2 slabs upon desodiation both theoretically and experimentally, which underlies the fundamental origin of the outstanding structural stability of HEO materials. As a consequence, the complex phase transitions (O3-O'3-P3-P'3-P3'-O3') of conventional O3-type cathode have been eliminated, and the as-obtained material demonstrates exceptional structural robustness and integrity with an ultra-long cycle life in a quasi-solid-state cell (maintaining 73.2% capacity after 1000 cycles at 2 C). Moreover, the material presents satisfactory air stability, with minimal structural and electrochemical degradation when directly exposed to the air. An Ah-scale pouch cell based on the cathode material is constructed, demonstrating a capacity retention of 83.6% after 500 cycles, signaling substantial promise for commercial applications.

DOI: 10.1002/anie.202416290

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202416290