The invention relates to a
power battery performance degradation prediction method and
system based on an electrochemical-thermal-mechanical-neural
network model, and belongs to the technical field of battery management. According to the method, an enhanced single
particle model considering
liquid phase diffusion, an integrated
thermal model, a particle mechanical stress model caused by
concentration gradient and an aging mechanism model considering SEI growth,
lithium precipitation and active material loss are coupled to establish ETMD, and based on the ETMD, the identification efficiency of aging
model parameters is low aiming at the problem that a PSO
algorithm is low. Under a circulating aging experiment of a limited path, the characteristic parameters of the aging model are obtained by using the
feedforward neural network, and the parameters are substituted into the ETMD model again to predict the capacity, the power
attenuation curve and the corresponding main attenuation mechanism under the current path, so that the prediction precision and the
interpretability of the performance attenuation of the battery under the full path are improved. According to the method, the modeling capability of battery performance degradation under different working conditions can be effectively improved, and a theoretical basis and
technical support are provided for residual life prediction and safety management of the
power battery.