Li Qi, Xu Sheng, Guo Shaohua, Jiang Kezhu, Li Xiang, Jia Min, Wang Peng, Zhou Haoshen
Energy Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8568, Japan.
College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, Nanjing University, Nanjing, 210093, China.
Adv Mater. 2020 Jun;32(23):e1907936. doi: 10.1002/adma.201907936. Epub 2020 Apr 27.
Sodium-ion batteries are in high demand for large-scale energy storage applications. Although it is the most prevalent cathode, layered oxide is associated with significant undesirable characteristics, such as multiple plateaus in the charge-discharge profiles, and cation migration during repeated cycling of Na-ions insertion and extraction, which results in sluggish kinetics, capacity loss, and structural deterioration. Here, a new strategy, i.e., the manipulation of transition-metal ordering in layered oxides, is proposed to show a prolonged charge-discharge plateau and cation-migration-free structural evolution. The results demonstrate that the transition-metal ordering with a honeycomb-type superlattice can adjust the crystal lattice and suppress cation migration by modifying the crystal strain to realize a large reversible capacity and excellent cycling performance, which are not characteristics of the widely used common layered oxides. These findings can provide new insight that can be used to improve the design of high-performance electrode materials for secondary-ion batteries.
钠离子电池在大规模储能应用中需求旺盛。尽管层状氧化物是最普遍的正极材料，但它存在显著的不良特性，如充放电曲线中的多个平台，以及在钠离子嵌入和脱出的反复循环过程中的阳离子迁移，这导致动力学迟缓、容量损失和结构劣化。在此，提出了一种新策略，即操纵层状氧化物中的过渡金属有序排列，以展现出延长的充放电平台和无阳离子迁移的结构演变。结果表明，具有蜂窝型超晶格的过渡金属有序排列可以通过改变晶格应变来调整晶格并抑制阳离子迁移，从而实现大的可逆容量和优异的循环性能，而这些并非广泛使用的普通层状氧化物的特性。这些发现可为改进二次离子电池高性能电极材料的设计提供新的见解。
