GB/T 41232.2-2021 "Nanofabrication, Key Control Characteristics, Nano Energy Storage, Part 2: Density Testing of Nano-anode Materials" is a special project standard in the field of nano-energy storage, which clarifies the principle, equipment requirements, operation process and data processing specifications of nano-anode material density testing. The standard is suitable for the density detection scenario of anode materials for nano-energy storage devices, providing a unified technical basis for product mass control, R & D and performance evaluation, ensuring the accuracy and comparability of test results, and helping the standardization and high-mass development of nano-manufacturing and energy storage industries.