New energy storage is an important technology and basic equipment supporting the new power system, which is of great significance for promoting green energy transformation, responding to extreme events, ensuring energy security, promoting high-quality energy development, and supporting the achievement of the “dual carbon” goal. This article proposes a cooperative game theory-based capacity optimization method for multi-type energy storage systems. The objective function is to minimize the investment cost of energy storage, and the search algorithm is used to solve the problem. Finally, a case study is conducted using multiple types of energy storage systems in a certain region to compare and analyze the impact of different new energy utilization rates on energy storage capacity configuration. The results shows that the proposed method can improve the economics of hybrid energy storage capacity configuration.