With the rapid progress of computer technology, computational research exhibits significant advantages in investigating microstructure evolution of material systems. As a computational research method of material dynamics, increasing attention has been paid to the phase-field model because of its avoidance of complicated interface tracking and convenience of dealing with applied fields. Theoretical framework of the phase-field model and three current phase-field models for multicomponent multiphase systems (the Carter, Steinbach, and Chen models) are introduced and reviewed in terms of interpretation of phase-field variables, way of coupling thermodynamic database, way of constructing the free energy density, and evolution equations. This review only focuses on the application of the phase-field model in electrochemical energy storage materials, and introduces its existing phase-field simulation results, which demonstrates that the phase-field model has tremendous potential in describing the microstructure evolution (anisotropic transport and phase separation, elastic and plastic deformation, crack propagation and fracture, dendrite growth, etc) and improving the performance of electrochemical energy storage materials. Finally, from two aspects of improving phase-field theory and extending application, future development trend and problems to be solved of phase-field simulations in electrochemical energy storage materials are discussed and looked ahead.