This standard is a recommended national standard specifically for the determination of trace moisture in cathode materials for lithium-ion batteries. Its core specifies the use of the Karl Fischer coulometric method (also known as the coulometric method) to accurately measure the moisture content in various cathode materials such as lithium cobalt oxide, lithium nickel cobalt manganese oxide, and lithium iron phosphate, covering a detection range from 0.0005% to 0.5000%. The method is based on chemical and electrochemical principles, where iodine is generated electrolytically by the instrument and undergoes a quantitative reaction with water in the sample. The moisture content is calculated based on the amount of electricity consumed. This method is characterized by its extremely high sensitivity, making it particularly suitable for the analysis of trace and ultra-trace moisture. Implementing this standard requires the use of specialized Karl Fischer moisture titrators, particularly those of the coulometric (coulometric method) type, and is typically combined with auxiliary equipment such as Karl Fischer ovens to ensure complete evaporation of moisture from the sample and its delivery into the titration cell for reaction.