▎ 摘 要
NOVELTY - A negative active material comprises graphene and metal phosphate particles dispersed on graphene surfaces, and having ratio of number of metal phosphate particles having a particle diameter of 10-40 nm to the total number of metal phosphate particles of 0.8 or more. USE - Negative active material for sodium secondary battery (claimed). ADVANTAGE - The negative material has improved electrical conductivity, high capacity due to the presence of metal phosphate having uniform size, and is economically prepared by simple method. The negative material provides the battery with improved electrochemical property and excellent charge and discharge capacity, and discharge retention. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) preparation of negative active material; and (2) sodium secondary battery.