Abstract: With the rapid development of renewable energy, the energy storage system is increasingly important to maintain the power balance of the power grid. A microgrid model for capacity of new energy hybrid energy storage system is established to realize the optimal configuration of storage capacity in the wind-solar complementary microgrid, thereby improving the power supply quality. on the energy mapping relationship, the alternating direction method of multipliers is used to iteratively solve the optimal number of decomposition modes, and the high and low frequency boundary points are selected to the characteristics of supercapacitors and batteries, and the corresponding power is calculated. Case studies show that the proposed method can not only improve the service life of batteries, but reduce the annual comprehensive cost.