上海科技大学知识管理系统

Understanding the atomistic mechanisms of non-equilibriumprocessesduring solid-state synthesis, such as nucleation and grain structureformation of a layered oxide phase, is a critical challenge for developingpromising cathode materials such as Ni-rich layered oxide for Li-ionbatteries. In this study, we found that the aluminum oxide coatinglayer transforms into lithium aluminate as an intermediate, whichhas favorable low interfacial energies with the layered oxide to promotethe nucleation of the latter. The fast and uniform nucleation andformation of the layered oxide phase at relatively low temperatureswere evidenced using solid-state nuclear magnetic resonance and insitu synchrotron X-ray diffraction. The resulting Ni-rich layeredoxide cathode has fine primary particles, as visualized by three-dimensionaltomography constructed using a focused-ion beam and scanning electronmicroscopy. The densely packed fine primary particles enable the excellentmechanical strength of the secondary particles, as demonstrated byin situ compression tests. This strategy provides a new approach fordeveloping next-generation, high-strength battery materials.