The invention, which belongs to the technical field of battery management, relates to a lithium battery parameter identification method based on a composite working condition. The composite working condition is formed by N groups of cycles. Each cycle group includes a rapidly changing charge and discharge stage, a constant-current discharge stage, and a standing stage. At the standing stage of anycycle, tau2 is estimated according to a relationship between a battery terminal voltage and time; at the constant-current discharge stage of any cycle, the sum of three internal resistors R0, R1, andR3 is calculated based on the Ohm's law; for the first cycle by starting with SOC being equal to 100%, next cycle parameters R2 and C2 are used for replacement to avoid introduction of too many errors; and corresponding groups of battery model data are identified by the N cycle groups and a full-SOC-range battery model is constructed based on a table looking + linear interpolation method. According to the total capacity, the SOC corresponding to the battery after each constant-current discharge condition is calculated, open-circuit voltages under all SOCs are recorded, and a complete SOC-OCVcurve is obtained by fitting. The lithium battery parameter identification method has the following advantages: the parameter identification under different working conditions is considered fully; andthe robustness is high.