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With the development of new lithium-ion battery anode materials, such as silicon and tin, the mechanical analysis of the active material is important.Anode material graphites the theoretical specific capacity is far below the silicons.However, silicon in completely lithium enormous deformation will happen, leads to silicon cracking and crushing, thus seriously affects cycle performance.In view of the new type of silicon electrode have the features of large deformation, this paper adopts the theory of large deformation, the electrode diffusion stress and deformation are analyzed.When considering such materials as silicon, the large deformation theory rather than general small deformation theory should be adopted.Under the condition of low concentration, according to the calculation results of single layer electrode with large deformation model, the results are basically close to the results with small deformation model.With the process of charging, the concentration will be increased in the active layer, and the electrode deformation will be more obvious than the initial states.The results of small deformation and large deformation gap are farther than the initial states.Under the framework of large deformation, lithium ion concentration distribution will be more uniform, and hoop stress decreases significantly.With large deformation model the radial stress calculation is more accurate, when compared with small deformation model.Besides, when SOC > 5%, with the increase of SOC, electrode diffusion stress is monotonically decreasing.The charging rate is smaller, the same SOC diffusion electrode stress are smaller.This result provides a principle to us when designing electrode, which is requiring the elastic modulus of current collector should be small enough.In addition, in the initial charge or discharge state, the electric current should be small.If SOC > 5% (DOC > 5%), electric current can be larger.In this paper, the bilayer electrode stress evolution process of the electrode diffusion is also analyzed with the large deformation model.