A strategy for digital simulation methods was presented for solving partial differential equations, called as IPBFP which is to insert M points before the first time point of the usual way, to decrease simulation errors. The theoretical analysis and simulation results show that it can improve the fully implicit method with any dimensionless diffusion coefficient A, Crank-Nicolson method with large and Saul’yev method with small . The IPBFP is convenient to arrange the simulation time points flexibly and reduce calculation time and errors. This approach can combine the merits of non-uniform time grid and uniform time grid methods in simulation for electrochemical studies.