This standard provides unified technical specifications for the determination of the tap density of lithium-ion battery cathode material powders. It systematically defines the core content of the testing method, including its principles, equipment, testing procedures, and data processing. Powder tap density is a key parameter affecting battery energy density. The standard calculates the density value under compaction by applying specific pressure to cause displacement and deformation of the powder, filling the gaps between particles. During the testing process, an automatic powder tap density instrument equipped with a high-precision displacement sensor (resolution of 0.001 mm) must be used. The pressure (e.g., 5-20 tons) is precisely controlled via a servo or hydraulic power system, and real-time data such as stress, density, and displacement are collected through a 7-inch touchscreen and PC software to generate analytical graphs. Additionally, an analytical balance with an accuracy of one ten-thousandth (0.00001 g) is required to measure the sample mass, combined with a standard mold (e.g., inner diameter of 13 mm) for compaction. This provides reliable data support for the research, development, and quality control of new energy battery materials.