IEC 62973-4:20 21适用于机车车辆辅助供电系统的二次密封镍氢电池技术。 本文件规定了密封镍金属氢化物电池的特性和测试要求，并补充了IEC 62973-1，适用于任何类型的机车车辆（如轻轨车辆、有轨电车、有轨电车、地铁、通勤列车、区域列车、高速列车、机车等）。）.除非另有规定，否则适用IEC 62973-1的要求。本文件还规定了电池和电池充电器之间接口的要求。本文件应与IEC 62675、IEC 63115-1和IEC 63115-2结合使用。

IEC 62973-4:2021 applies to secondary sealed nickel-metal hydride battery technologies for auxiliary power supply systems used on rolling stock.
This document specifies the requirements of the characteristics and tests for the sealed nickel-metal hydride cells and supplements IEC 62973-1 which applies to any rolling stock types (e.g. light rail vehicles, tramways, streetcars, metros, commuter trains, regional trains, high speed trains, locomotives, etc.). Unless otherwise specified, the requirements of IEC 62973-1 apply. This document also specifies the requirements of the interface between the batteries and the battery chargers. This document is to be used in conjunction with IEC 62675, IEC 63115-1 and IEC 63115-2.