▎ 摘　　要

NOVELTY - Producing (P1) anode or negative electrode for lithium-ion battery, comprises: (a) dispersing catalyst metal-coated silicon particles, graphene sheets and optional blowing agent in liquid medium to get graphene/silicon dispersion; (b) dispensing and depositing graphene/silicon dispersion onto surface of supporting substrate to get wet layer of graphene/silicon mixture and partially or completely removing liquid medium from wet layer of graphene/silicon mixture to get dried layer of graphene/silicon mixture material; and (c) exposing dried layer of graphene/silicon mixture to high temperature. USE - The process is useful for producing an anode or negative electrode for a lithium-ion battery. ADVANTAGE - The process: is cost-effective; and provides graphene foam structures that exhibit higher thermal conductivity, higher electrical conductivity, minimal electrode volume changes, more effective anode-protecting capability, improved cycle stability and significantly higher energy storage capability to the high-capacity anodes. DETAILED DESCRIPTION - Producing (P2) an anode or negative electrode for a lithium-ion battery, the anode comprising a solid graphene foam composed of multiple pores and pore walls and silicon nanowires residing in the pores, comprises: (a) dispersing catalyst metal-coated silicon particles, graphene sheets and an optional blowing agent in a liquid medium to get a graphene/silicon dispersion, where the silicon particles have a particle diameter of 0.2-20 mu m and the catalyst metal is in a form of nano particles having a diameter of 0.5-100 nm or a thin coating having a thickness of 1-100 nm deposited on surfaces of the silicon particles and optionally on surfaces of graphene sheets, and the silicon particles contain pure silicon having at least 99.9 wt.% of silicon element or a silicon alloy or mixture having 70-99.9 wt.% of silicon in it; (b) dispensing and depositing the graphene/silicon dispersion onto a surface of a supporting substrate to get a wet layer of graphene/silicon mixture and partially or completely removing the liquid medium from the wet layer of graphene/silicon mixture to get a dried layer of graphene/silicon mixture material; and (c) exposing the dried layer of graphene/silicon mixture to a high temperature environment, including a temperature of 100-2500 degrees C to induce volatile gas molecules from the graphene sheets or to activate the blowing agent for producing the graphene foam and, concurrently, to enable a catalyst metal-catalyzed growth of multiple silicon nanowires emanating from the silicon particles as a feed material in pores of the graphene foam to get the anode electrode layer, where the silicon nanowires have a diameter of 2-100 nm and a length-to-diameter aspect ratio of at least 5 and the silicon nanowires are in a concentration of 0.5-99 wt.% based on the total weight of the graphene foam and the silicon nanowires combined. INDEPENDENT CLAIMS are also included for: (1) producing (P2) the anode or negative electrode layer for the lithium battery, the anode layer comprising a solid graphene foam composed of multiple pores and pore walls and silicon nanowires residing in the pores, comprising (a1) dispersing silicon particles, graphene sheets, a catalytic metal precursor and an optional blowing agent in a liquid to form a graphene/silicon dispersion, where the silicon particles have a diameter of 0.2-20 mu m and contain pure silicon having at least 99.9 wt.% of silicon element or a silicon alloy or mixture having 70-99.9 wt.% of silicon in it, (b1) dispensing and depositing the graphene/silicon dispersion onto a surface of a supporting substrate to form a wet layer of graphene/silicon mixture and partially or completely removing the liquid medium from the wet layer of graphene/silicon mixture to form a dried layer of graphene/silicon mixture material, and (c1) exposing the dried layer of graphene/silicon mixture to a high temperature environment of 100-2000 degrees C to thermally convert the catalytic metal precursor to coating or nano particles of a catalyst metal deposited on surfaces of silicon particles and/or surfaces of graphene sheets, to induce volatile gas molecules from the graphene sheets or to activate the blowing agent for producing the graphene foam, and concurrently or sequentially, to enable a catalyst metal-catalyzed growth of multiple silicon nanowires emanating from the silicon particles as a feed material in pores of the graphene foam to form the anode electrode layer, where the silicon nanowires have a diameter of less than 100 nm and a length-to-diameter aspect ratio of at least 5 and the silicon nanowires are in a concentration of 0.5-95 wt.% based on the total weight of the graphene foam and the silicon nanowires combined; (2) the anode produced by the process (P1), where the anode comprises graphene foam structure composed of multiple pores and pore walls and silicon nanowires residing in the pores, where the pore walls contain a three dimensional network of interconnected graphene planes or stacked graphene planes having an inter-plane spacing d002 from 0.3354-0.4 nm as measured by X-ray diffraction and the silicon nanowires have a diameter of 2-100 nm and a length-to-diameter aspect ratio of at least 5 and the silicon nanowires are in a concentration of 5-99 wt.% based on the total weight of the graphene foam and the Si nanowires combined; and (3) the lithium battery containing the anode, a cathode or positive electrode, and an electrolyte in ionic contact with the anode and the cathode.