A negative active material includes a carbon material. The carbon material satisfies the following relationship: 6<Gr/K<16, Gr is a graphitization degree of the carbon material, measured by X-ray diffraction; and K is a ratio Id/Ig of a peak intensity Id of the carbon material at a wavenumber of 1250 cm.sup.−1 to 1650 cm.sup.−1 to a peak intensity Ig of the carbon material at a wavenumber of 1500 cm.sup.−1 to 1650 cm.sup.−1, and is measured by using Raman spectroscopy, and K is 0.06 to 0.15.

A negative electrode material includes silicon-based particles and graphite particles. In a case that a D.sub.n50/D.sub.v50 ratio of the graphite particles is A and a D.sub.n50/D.sub.v50 ratio of the silicon-based particles is B, the following conditional expressions (1) to (3) are satisfied: 0.1≤A≤0.65 (1); 0.3≤B≤0.85 (2); and B>A (3), where, D.sub.v50 is a particle diameter of particles measured when a cumulative volume fraction in a volume-based distribution reaches 50%, and D.sub.n50 is a particle diameter of particles measured when a cumulative number fraction in a number-based distribution reaches 50%. The present invention further provides a negative electrode plate, a lithium-ion secondary battery or electrochemical device containing the negative electrode plate, and an electronic device containing the lithium-ion secondary battery and/or electrochemical device.

Provided is a method of producing multiple isolated hollow graphene balls, comprising: (a) mixing multiple particles of a graphitic material and multiple particles of a solid polymer carrier material to form a mixture in an impacting chamber of an energy impacting apparatus; (b) operating the energy impacting apparatus to peel off graphene sheets from the graphitic material and transferring the graphene sheets to surfaces of solid polymer carrier material particles to produce graphene-coated polymer particles; (c) recovering the graphene-coated polymer particles from the impacting chamber; and (d) suspending the graphene-encapsulated polymer particles in a gaseous medium to keep the particles separated from each other while concurrently pyrolyzing the particles to thermally convert polymer into pores and carbon, wherein at least one of the graphene balls comprises a hollow core enclosed by a shell composed of graphene sheets bonded together by carbon.

Provided is a method of producing multiple isolated hollow graphene balls, comprising: (a) mixing multiple particles of a graphitic material and multiple particles of a solid polymer carrier material to form a mixture in an impacting chamber of an energy impacting apparatus; (b) operating the energy impacting apparatus to peel off graphene sheets from the graphitic material and transferring the graphene sheets to surfaces of solid polymer carrier material particles to produce graphene-coated polymer particles; (c) recovering the graphene-coated polymer particles from the impacting chamber; and (d) suspending the graphene-encapsulated polymer particles in a gaseous medium to keep the particles separated from each other while concurrently pyrolyzing the particles to thermally convert polymer into pores and carbon, wherein at least one of the graphene balls comprises a hollow core enclosed by a shell composed of graphene sheets bonded together by carbon.

A method of producing advanced carbon materials can include providing coal to a processing facility, beneficiating the coal to remove impurities from the coal, processing the beneficiated coal to produce a pitch, and treating the pitch to produce an advanced carbon material such as carbon fibers, carbon nanotubes, graphene, resins, polymers, biomaterials, or other carbon materials.

A method of producing advanced carbon materials can include providing coal to a processing facility, beneficiating the coal to remove impurities from the coal, processing the beneficiated coal to produce a pitch, and treating the pitch to produce an advanced carbon material such as carbon fibers, carbon nanotubes, graphene, resins, polymers, biomaterials, or other carbon materials.

The invention is directed to a thermally expandable composition comprising at least one solid rubber, at least on tackifying resin, a vulcanization system, and a thermally expandable graphite. The invention is also directed to a welding sealer tape comprising a substrate layer composed of the thermally expandable composition, to a method for providing sealing, structural adhesion, baffling, or combination thereof to a structure of a manufactured article, to a baffle and/or reinforcing element comprising the thermally expandable composition, to a method for sealing, baffling and/or reinforcing a cavity or a hollow structure, and to use of a thermally expandable graphite as a blowing agent in a thermally expandable material.

The invention is directed to a thermally expandable composition comprising at least one solid rubber, at least on tackifying resin, a vulcanization system, and a thermally expandable graphite. The invention is also directed to a welding sealer tape comprising a substrate layer composed of the thermally expandable composition, to a method for providing sealing, structural adhesion, baffling, or combination thereof to a structure of a manufactured article, to a baffle and/or reinforcing element comprising the thermally expandable composition, to a method for sealing, baffling and/or reinforcing a cavity or a hollow structure, and to use of a thermally expandable graphite as a blowing agent in a thermally expandable material.

An electrode material for a lithium ion secondary battery and method of forming the same, the electrode material including composite particles, each composite particle including: a primary particle including an electrochemically active material; and an envelope disposed on the surface of the primary particle. The envelope includes turbostratic carbon having a Raman spectrum having: a D band having a peak intensity (I.sub.D) at wave number between 1330 cm.sup.-1 and 1360 cW.sup.-1; a G band having a peak intensity (I.sub.G) at wave number between 1530 cm.sup.-1 and 1580 cm.sup.-1; and a 2D band having a peak intensity (I.sub.2D) at wave number between 2650 cm.sup.-1 and 2750 cm.sup.-1. In one embodiment, a ratio of I.sub.D/I.sub.G ranges from greater than zero to about 1.1, and a ratio of 1.sub.2D/I.sub.G ranges from about 0.4 to about 2.

The objective of the present invention is to provide a carbon material excellent in conductivity. The carbon material according to the present invention has a graphene sheet as a basic skeleton and is doped with boron so that carbon is substituted with boron, the carbon material being characterized in that the boron content in the carbon material is 0.005-15 mol %, and when the content of dopant boron that substitutes carbon on the surface of the carbon material is denoted by X (mol %) and the content of boron in the carbon material is denoted by Y (mol %), X/Y<0.8 is satisfied.