Chang Miao, Cheng Fangyuan, Zhang Wen, Liao Mengyi, Li Qing, Fang Chun, Han Jiantao
State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
ACS Nano. 2025 Jan 14;19(1):712-721. doi: 10.1021/acsnano.4c11901. Epub 2024 Dec 25.
Surface engineering is sought to stabilize nickel-rich layered oxide cathodes in high-energy-density lithium-ion batteries, which suffer from severe surface oxygen loss and rapid structure degradation, especially during deep delithiation at high voltages or high temperatures. Here, we propose a well-designed oxygen-constraining strategy to address the crisis of oxygen evolution. By integrating a La, Fe gradient diffusion layer and a LaFeO coating into the Ni-rich layered particles, along with incorporating an antioxidant binder into the electrodes, three progressive lines of defense are constructed: immobilizing the lattice oxygen at the subsurface, blocking the released oxygen at the interface, and capturing the residual singlet oxygen on the external surface. As a result, effective surface passivation, mitigated bulk and surface degradation, suppressed side reactions, and enhanced electrochemical performance are achieved, far beyond conventional single surface modification. The Ni-rich layered oxide cathodes with integrated oxygen-constraining modifications demonstrate impressive cycling stability in both half-cells and full cells, achieving stable long-term cycling even at a high cutoff voltage of 4.7 V and a high temperature of 45 °C. This work provides a multilevel oxygen-constraining strategy, which can be extended to various layered oxide cathodes involving oxygen release challenges, providing an effective path for the development of high-energy-density lithium-ion batteries.
表面工程旨在稳定高能量密度锂离子电池中富镍层状氧化物阴极，这类阴极存在严重的表面氧损失和快速的结构降解问题，尤其是在高电压或高温下深度脱锂过程中。在此，我们提出一种精心设计的氧约束策略来应对析氧危机。通过将La、Fe梯度扩散层和LaFeO涂层整合到富镍层状颗粒中，并在电极中加入抗氧化粘结剂，构建了三道递进的防线：将次表面的晶格氧固定、在界面处阻挡释放的氧、在外表面捕获残留的单线态氧。结果实现了有效的表面钝化、减轻了体相和表面降解、抑制了副反应并提高了电化学性能，远远超过传统的单表面改性。具有集成氧约束改性的富镍层状氧化物阴极在半电池和全电池中均表现出令人印象深刻的循环稳定性，即使在4.7 V的高截止电压和45℃的高温下也能实现稳定的长期循环。这项工作提供了一种多级氧约束策略，可扩展到各种面临氧释放挑战的层状氧化物阴极，为高能量密度锂离子电池的发展提供了一条有效途径。
