Research on Comprehensive Assessment Method of Battery Consistency Based on Scaled Energy Storage Power Station

In the long-term operation of a megawatt-scale energy storage plant composed of series-parallel connections, the single batteries will have different degrees of inconsistency problems. To solve this problem, this paper proposes a comprehensive assessment method based on the consistency of batteries in scaled energy storage power stations. According to the consistency indexes such as single battery voltage and voltage polarity difference in series connection between modules, the consistency evaluation criterion of battery monomer was established. Based on the historical data of a battery energy storage system, the consistency evaluation criterion of a single battery is used to analyze the consistency of a single battery of an energy storage power station at different charging and discharging stages. The results show that this method can accurately assess cell consistency. It provides data support for the health status assessment of energy storage plants and reduces the systematic operational risk of energy storage plants.