Abstract: Grid-side energy storage is an effective means of operation regulation， which provides a flexible guarantee for the security and stability of the power grid. With the high penetration of new energy and the rapid development of UHV power grids， grid security issues such as system fluctuations are becoming increasingly serious. In the power grid， a high proportion， widely existing， and wide-area collaborative energy storage model needs to be constructed. Therefore， it is of great significance to carry out technical research on energy storage on the grid side. This paper introduces current situation of research on grid-side energy storage technology and commercial demonstration project； summarizes methods for grid-side energy storage in site selection and optimization allocation； analyzes the demand of grid-side energy storage through theory and time-series indicators； expounds the optimization allocation technology and economic evaluation parameters in energy storage； and points out the difficult problems in promoting the application. Finally， the paper gives suggestions and prospects for development in grid-side energy storage technology， which has certain reference significance for exploiting the value in energy storage applications and innovating energy storage application business model.

Key words: electrochemical energy storage, site selection for energy storage, energy storage configuration, demand analysis, economic evaluation