位错对锂电池球形颗粒电极的影响

摘要

目前对锂离子电池的研究主要集中在扩散引起的应力方面，但有关应力引起的位错对锂电池电极影响目前还鲜有报道。建立了一个球位错模型，进而研究了位错机制对球形纳米颗粒电极中应力变化的影响。由于位错的产生和分布，电极的径向和切向张应力都被减轻了，并且电极中的压应力的大小有了一定的提高。通过研究发现减少的张应力转化成了压应力，然而张应力影响电极裂纹的萌生，那么可以得出一个结论，即引入位错机制可能会优化电极的扩散应力，从而提高电极的寿命。%Recent researches on lithium ion cellconcentrate on stress induced by diffusion. However, the effect of the dislocation induced by stress on lithium ion battery electrode is fewly reported. A spherical dislocation model was developed to study the effect of dislocation on stress change in spherical nanoparticle electrode. Due to the generation and distribution of dislocation, the radial and tangential tensile stress are significant reduced, and the compressive stress in the electrode increases. It is clear that the decreased tensile stress which affects the formation of crack is converted into compressive stress. A suggestion can be driven that bringing into the dislocation mechanics can optimize the diffusion stress and prolong electrode life.