The current electrochemical model of lithium-ion power battery has the problems of complex model, difficult modeling, low calculation efficiency, and poor aging evaluation effect. This paper proposes a mechanism model (ADME) that considers battery degradation and aging. In this paper, the pseudo two-dimensional (P2D) electrochemical model is discretely reduced by the finite difference method to obtain a simplified pseudo two-dimensional (SP2D) model. On the basis of the SP2D model, based on the degradation and aging phenomenon caused by the side reactions of the positive and negative poles, a mechanism model (ADME) that considers the degradation and aging of the battery is proposed. Secondly, the multivariate deviation compensation least square method is used to realize the model parameter identification. Finally, the terminal voltage output of the SP2D model and the ADME model are compared and analyzed through the cyclical experiment of power battery degradation and aging performance, constant current and pulse operating conditions. The results show that the ADME model is relatively simple, has high calculation efficiency and estimation accuracy, and can effectively evaluate the aging and decline of battery capacity, and obtain an ideal lithium-ion power battery external characteristic curve.