A novel surface modification approach for graphite anode of lithium-ion batteries was developed in this study. Ionic conductive copolymer poly{[oligo(oxyethylene)methylacrylate]-co-(methylacrylic acid lithium)} [poly(MEO8-MALi)] was in situ encapsulated on the surface of natural graphite particles by means of radiation-initiated polymerization. After the encapsulation, the cointercalation of solvated Li+ in propylene carbonate-based electrolyte during the first cycle was depressed successfully and cyclability was improved. The stability of the solid electrolyte interface film formed on the encapsulated graphite electrode was enhanced during the cycling, which was demonstrated by electrochemical impedance spectroscopy and scanning electron microscope.