The wide application of distributed energy storage has effectively solved many problems caused by large-scale distributed generation (DG) access to the distribution network and the rapid increase of load on the planning and operation of the power grid. Distributed energy storage has the characteristics of fast power throughput,high control accuracy,flexible installation,and multi-subject benefits,which can effectively ensure the safety and stability of power supply in the distribution network. The development status of distributed energy storage is sorted out. The advantages and disadvantages of distributed energy storage application modes at home and abroad are analyzed in recent years according to its access location on the DG side,the medium and low voltage distribution network side,the user and the microgrid side. Various mathematical models and optimization algorithms for the optimal configuration of distributed energy storage are compared and analyzed in terms of its location and capacity. Combined with the problems existing in the configuration process of distributed energy storage,the development trend of distributed energy storage is prospected.