▎ 摘　　要

NOVELTY - The method involves ball-milling a mixture to obtain a phosphorus-carbon composite. The mixture comprises a first precursor and a second precursor for a conductive carbon matrix, and phosphorus. An anode is prepared with the phosphorus-carbon composite. The electrochemical device is assembled with the anode. The first precursor comprises multiple graphites, graphene, expanded graphite, reduced graphene oxide, acetylene black, carbon black, a metal-organic framework, porous carbon, carbon spheres, or carbon aerogel. The second precursor comprises multiple single-walled carbon nanotubes, multi-walled carbon nanotubes, carbon nanofibers, carbon nanotube arrays, polypyrrole, or polyaniline. The phosphorus-carbon composite comprises nano-sized phosphorus particles uniformly dispersed on the surface and pores of the carbon matrix. The nano-sized phosphorus particles comprise black phosphorus, and the ball-milling is performed at a rotation speed of about 700 to about 1500 rpm. USE - Method for preparing electrochemical device. ADVANTAGE - The nano-sized particles of phosphorus produced during a high energy ball milling process can shorten the diffusion path of cations and accommodate the volume changes during repeated charge/discharge. The high surface area of the conductive carbon matrix enables a uniform dispersion of phosphorus nano-sized particles in the phosphorus-carbon composite, which can prevent the aggregation of phosphorus particles during charge/discharge cycling. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into equal halves, thirds, quarters, fifths, tenths, etc. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a sodium-ion battery. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a representation of high energy ball milling process.