Capacity testing revolves around two primary metrics: nominal capacity (rated energy storage) and actual usable capacity under operational conditions. Unlike basic voltage checks, this process requires controlled discharge/charge cycles at specified C-rates (0. 5%. . This report describes development of an effort to assess Battery Energy Storage System (BESS) performance that the U. As global industries prioritize longer runtime and faster charging for applications ranging from EVs to grid storage, standardized. . Power capacity or power rating: The maximum amount of power that a battery can instantaneously produce on a continuing basis. It can be compared to the nameplate rating of a power plant. Power capacity or rating is measured in megawatts (MW) for larger grid-scale projects and kilowatts (kw) for. . Battery capacity testing is a critical process in evaluating the performance, health, and reliability of batteries used in various applications, from consumer electronics to electric vehicles and renewable energy storage systems.