Yu Yang, Mao Qianjiang, Wong Deniz, Gao Rui, Zheng Lirong, Yang Wenyun, Yang Jinbo, Zhang Nian, Li Zeyu, Schulz Christian, Liu Xiangfeng
Center of Materials Science and Optoelectronics Engineering, College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Department of Dynamics and Transport in Quantum Materials, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, Berlin 14109, Germany.
J Am Chem Soc. 2024 Aug 14;146(32):22220-22235. doi: 10.1021/jacs.4c02782. Epub 2024 Aug 1.
High-voltage layered oxide cathodes attract great attention for sodium-ion batteries (SIBs) due to the potential high energy density, but high voltage usually leads to rapid capacity decay. Herein, a stable high-voltage NaLiNiMnTiO cathode with a ribbon-ordered superlattice is reported, and the intrinsic coupling mechanism between structure evolution and the anion redox reaction (ARR) is revealed. Li introduction constructs a special Li-O-Na configuration activating reversible nonbonded O 2p (|O)-type ARR and regulates the structure evolution way, enabling the reversible Li ions out-of-layer migration instead of the irreversible transition metal ions out-of-layer migration. The reversible structure evolution enhances the reversibility of the bonded O 2p (O)-type ARR and inhibits the generation of oxygen dimers, thus suppressing the irreversible molecular oxygen (O)-type ARR. After the structure regulation, the structure evolution becomes reversible, |O-type ARR is activated, O-type ARR becomes stable, and O-type ARR is inhibited, which largely suppresses the capacity degradation and voltage decay. The discharge capacity is increased from 154 to 168 mA h g, the capacity retention after 200 cycles significantly increases from 35 to 84%, and the voltage retention increases from 78 to 93%. This study presents some guidance for the design of high-voltage, O3-type oxide cathodes for high-performance SIBs.
高压层状氧化物阴极因其潜在的高能量密度而在钠离子电池（SIBs）领域备受关注，但高电压通常会导致容量快速衰减。在此，报道了一种具有带状有序超晶格的稳定高压NaLiNiMnTiO阴极，并揭示了结构演变与阴离子氧化还原反应（ARR）之间的内在耦合机制。锂的引入构建了一种特殊的Li-O-Na构型，激活了可逆的非键合O 2p（|O）型ARR，并调节了结构演变方式，使得锂离子能够进行可逆的层外迁移，而不是过渡金属离子的不可逆层外迁移。可逆的结构演变增强了键合O 2p（O）型ARR的可逆性，并抑制了氧二聚体的生成，从而抑制了不可逆的分子氧（O）型ARR。经过结构调控后，结构演变变得可逆，|O型ARR被激活，O型ARR变得稳定，且O型ARR受到抑制，这在很大程度上抑制了容量衰减和电压衰减。放电容量从154 mA h g提高到168 mA h g，200次循环后的容量保持率从35%显著提高到84%，电压保持率从78%提高到93%。该研究为高性能SIBs的高压O3型氧化物阴极设计提供了一些指导。
