This standard specifies methods for testing magnetic foreign matter content in electrode materials for lithium ion batteries, including terms and definitions, overview of test methods, required instruments and appliances, reagents, Environmental requirements, pretreatment, instrumental analysis, calculation of results, precision and reporting. Applicable for the detection of magnetic foreign matter content between 10 μg/kg~ 5,000 μg/kg in anode and cathode powder materials for lithium ion batteries and their slurries. Not applicable to lithium iron phosphoric acid materials. Overview of test methods includes dissolving the sample and detecting the content of elements such as iron, chromium, nickel, zinc by Inductance Coupled Plasma Emission Light Spectrometer.