IEC 60933 does not apply to energy storage systems; it relates to printed board design. You likely meant IEC 62933, which is the series of international standards for electrical energy storage (EES) systems. IEC 62933 provides a comprehensive framework for performance, safety, testing, and grid integration of BESS and other energy storage technologies. It includes general principles, system guidelines, and testing protocols for safe and efficient deployment of energy storage in power systems.