A comprehensive techno-economic analysis framework of battery energy storage system (BESS) is proposed. In this framework, a detailed battery degradation model is embedded, which models the influencing factors, such as depth-of-[JP]discharge, temperature, charging/discharging rate, and state of charge in the battery aging process. Total energy throughput and levelized cost of storage of BESS over the whole lifespan are evaluated under different operating conditions. Also, the techno-economic performance of BESS under different electricity price mechanisms is analyzed, including the time-of-use plan and the real-time pricing mechanism.