锂离子电池高镍层状氧化物正极结构失效机制

Structural Degradation of Ni-Rich Layered Oxide Cathode for Li-Ion Batteries

高镍层状氧化物具有成本低、能量密度高的优点,被认为是新一代锂离子电池的理想正极材料。然而,由于在使用中其结构的耐久性与安全性问题,在实际应用过程中仍然面临着严峻的挑战。深入了解电极材料容量衰减过程中的结构演变对发展高性能层状氧化物电极材料具有重要的指导意义。本文综述了近年来高镍层状氧化物正极失效机理的研究进展,包括从高镍层状氧化物的内部结构演变、表面成分变化和热失控条件下的性质等方面,进行了详细的梳理。之后,本文介绍了国内外最新的高镍层状氧化物的改性策略,并对高镍氧化物正极结构研究的发展方向进行了总结和展望。

Nickel(Ni)-rich layered oxide has been regarded as one of the most important cathode materials for the lithium-ion batteries because of its low cost and high energy density.However,the concerns in safety and durability of this compound are still challenging for its further development.On this account,the in-depth understanding in the structural factors determining its capacity attenuation is essential.In this review,we summarize the recent advances on the degradation mechanisms of Ni-rich layered oxide cathode.Progresses in the structure evolution of Ni-rich oxide are carefully combed in terms of inner evolution,surface evolution,and the property under thermal condition,while the state-of-the-art modification strategies are also introduced.Finally,we provide our perspective on the future directions for investigating the degradation of Ni-rich oxide cathode.