Abstract: A method for making a sulfur-graphene composite material is provided. In the method, an elemental sulfur solution and a graphene dispersion are provided. The elemental sulfur solution includes a first solvent and an elemental sulfur dissolved in the first solvent. The graphene dispersion includes a second solvent and graphene sheets dispersed in the second solvent. The elemental sulfur solution is added to the graphene dispersion, a number of elemental sulfur particles are precipitated and attracted to a surface of the graphene sheets to form the sulfur-graphene composite material. The sulfur-graphene composite material is separated from the mixture.

Abstract: A method for making a sulfur-graphene composite material is provided. In the method, an elemental sulfur solution and a graphene dispersion are provided. The elemental sulfur solution includes a first solvent and an elemental sulfur dissolved in the first solvent. The graphene dispersion includes a second solvent and graphene sheets dispersed in the second solvent. The elemental sulfur solution is added to the graphene dispersion, a number of elemental sulfur particles are precipitated and attracted to a surface of the graphene sheets to form the sulfur-graphene composite material. The sulfur-graphene composite material is separated from the mixture.

Abstract: A method for cycling a sulfur composite lithium ion battery includes a step of charging and discharging the sulfur composite lithium ion battery at a first voltage range between a predetermined highest voltage and a predetermined lowest voltage. The lithium ion battery includes an electrode active material. The electrode active material includes a sulfur composite. The step of charging and discharging satisfies at least one conditions of (1) and (2): (1) the predetermined lowest voltage of the first voltage range is larger than a discharge cutoff voltage of the sulfur composite; and (2) the predetermined highest voltage of the first voltage range is smaller than a charge cutoff voltage of the sulfur composite. A method for using a sulfur composite as an electrode active material of a lithium ion battery is also disclosed.

Abstract: In the method for making graphene, an electrolyte solution is formed by dissolving an electrolyte lithium salt in an organic solvent. Lithium ions are separated out from the electrolyte lithium salt in the electrolyte solution. Metal lithium and graphite are disposed in the electrolyte solution, and the metal lithium and the graphite are in contact with each other. In the electrolyte solution, lithium ions and organic solvent molecules jointly insert between adjacent layers of the graphite to form a graphite intercalation compound. The graphene is peeled off from the graphite intercalation compound.

Abstract: A method for making an anode active material is described. The anode active material includes a phosphorus composite material. In the method, a solid-state red phosphorus and a porous conductive carbon material are provided. The solid-state red phosphorus and the porous conductive carbon material are spaced disposed in a vessel and the vessel is sealed. The solid-state red phosphorus is sublimed by heating the vessel to make the sublimed red phosphorus diffused in the porous conductive carbon material. The sublimed red phosphorus is condensed. The condensed red phosphorus adsorbs in the porous conductive carbon material to form the phosphorus composite material.

Abstract: A lithium iron phosphate hierarchical structure includes a plurality of lithium iron phosphate nano sheets and has an overall spherical-shaped structure. The overall spherical-shaped structure is constructed by a plurality of lithium iron phosphate nano sheets layered together. A method for making a lithium iron phosphate hierarchical structure includes several steps. In the method, a lithium ion contained liquid solution, a ferrous ion contained liquid solution, and a phosphate ion contained liquid solution are respectively provided. A concentration of lithium ions in the lithium ion contained liquid solution is equal to or larger than 1.8 mol/L. The lithium ion contained liquid solution, the ferrous ion contained liquid solution, and the phosphate ion contained liquid solution are mixed to form a liquid mixture. The liquid mixture is heated in a sealed reactor to form the lithium iron phosphate hierarchical structure.

Abstract: A lithium ion battery includes a cathode electrode, an anode electrode, and an electrolyte. The anode electrode is spaced from the cathode electrode. The anode electrode includes an anode active material. The anode active material includes sulfur grafted poly(pyridinopyridine). The sulfur grafted poly(pyridinopyridine) includes a poly(pyridinopyridine) matrix and sulfur dispersed in the poly(pyridinopyridine) matrix. The electrolyte is located between the cathode electrode and the anode electrode.

Abstract: The present disclosure relates to a sulfurized polyacrylonitrile and a lithium-ion battery cathode active material. The sulfurized polyacrylonitrile includes a structural unit. A general molecular formula of the structural unit is C3HNSn, in which n is a positive integer. The lithium-ion battery cathode active material includes sulfurized polyacrylonitrile and a sulfurized polyacrylonitrile with inserted ions.

Abstract: A method for making sulfur-graphene composite material is disclosed. In the method, a dispersed solution including a solvent and a plurality of graphene sheets dispersed in the solvent is provided. A sulfur-source chemical compound is dissolved into the dispersed solution to form a mixture. A reactant, according to the sulfur-source chemical compound, is introduced to the mixture. Elemental sulfur is produced on a surface of the plurality of graphene sheets due to a redox reaction between the sulfur-source chemical compound and the reactant, to achieve the sulfur-graphene composite material. The sulfur-graphene composite material is separated from the solvent.

Abstract: A method for cycling a sulfur composite lithium ion battery includes a step of charging and discharging the sulfur composite lithium ion battery at a first voltage range between a predetermined highest voltage and a predetermined lowest voltage. The lithium ion battery includes an electrode active material. The electrode active material includes a sulfur composite. The step of charging and discharging satisfies at least one conditions of (1) and (2): (1) the predetermined lowest voltage of the first voltage range is larger than a discharge cutoff voltage of the sulfur composite; and (2) the predetermined highest voltage of the first voltage range is smaller than a charge cutoff voltage of the sulfur composite. A method for using a sulfur composite as an electrode active material of a lithium ion battery is also disclosed.

Abstract: A lithium ion battery includes a cathode electrode, an anode electrode, and an electrolyte. The anode electrode is spaced from the cathode electrode. The anode electrode includes an anode active material. The anode active material includes sulfur grafted poly(pyridinopyridine). The sulfur grafted poly(pyridinopyridine) includes a poly(pyridinopyridine) matrix and sulfur dispersed in the poly(pyridinopyridine) matrix. The electrolyte is located between the cathode electrode and the anode electrode.

Abstract: A method for making an anode active material is described. The anode active material includes a phosphorus composite material. In the method, a solid-state red phosphorus and a porous conductive carbon material are provided. The solid-state red phosphorus and the porous conductive carbon material are spaced disposed in a vessel and the vessel is sealed. The solid-state red phosphorus is sublimed by heating the vessel to make the sublimed red phosphorus diffused in the porous conductive carbon material. The sublimed red phosphorus is condensed. The condensed red phosphorus adsorbs in the porous conductive carbon material to form the phosphorus composite material.

Abstract: A method for making sulfur-graphene composite material is disclosed. In the method, a dispersed solution including a solvent and a plurality of graphene sheets dispersed in the solvent is provided. A sulfur-source chemical compound is dissolved into the dispersed solution to form a mixture. A reactant, according to the sulfur-source chemical compound, is introduced to the mixture. Elemental sulfur is produced on a surface of the plurality of graphene sheets due to a redox reaction between the sulfur-source chemical compound and the reactant, to achieve the sulfur-graphene composite material. The sulfur-graphene composite material is separated from the solvent.

Abstract: A method for making a sulfur-graphene composite material is provided. In the method, an elemental sulfur solution and a graphene dispersion are provided. The elemental sulfur solution includes a first solvent and an elemental sulfur dissolved in the first solvent. The graphene dispersion includes a second solvent and graphene sheets dispersed in the second solvent. The elemental sulfur solution is added to the graphene dispersion, a number of elemental sulfur particles are precipitated and attracted to a surface of the graphene sheets to form the sulfur-graphene composite material. The sulfur-graphene composite material is separated from the mixture.

Abstract: In the method for making graphene, an electrolyte solution is formed by dissolving an electrolyte lithium salt in an organic solvent. Lithium ions are separated out from the electrolyte lithium salt in the electrolyte solution. Metal lithium and graphite are disposed in the electrolyte solution, and the metal lithium and the graphite are in contact with each other. In the electrolyte solution, lithium ions and organic solvent molecules jointly insert between adjacent layers of the graphite to form a graphite intercalation compound. The graphene is peeled off from the graphite intercalation compound.

Abstract: A lithium iron phosphate hierarchical structure includes a plurality of lithium iron phosphate nano sheets and has an overall spherical-shaped structure. The overall spherical-shaped structure is constructed by a plurality of lithium iron phosphate nano sheets layered together. A method for making a lithium iron phosphate hierarchical structure includes several steps. In the method, a lithium ion contained liquid solution, a ferrous ion contained liquid solution, and a phosphate ion contained liquid solution are respectively provided. A concentration of lithium ions in the lithium ion contained liquid solution is equal to or larger than 1.8 mol/L. The lithium ion contained liquid solution, the ferrous ion contained liquid solution, and the phosphate ion contained liquid solution are mixed to form a liquid mixture. The liquid mixture is heated in a sealed reactor to form the lithium iron phosphate hierarchical structure.

Abstract: The present disclosure relates to a method for making a conjugated polymer. In the method, polyacrylonitrile, a solvent, and a catalyst are provided. The polyacrylonitrile is dissolved in the solvent to form a polyacrylonitrile solution. The catalyst is uniformly dispersed into the polyacrylonitrile solution. The polyacrylonitrile solution with the catalyst is heated to induce a cyclizing reaction of the polyacrylonitrile, thereby forming a conjugated polymer solution with the conjugated polymer dissolved therein.

Abstract: In a method for making sulfurized polyacrylonitrile, polyacrylonitrile, a first solvent, a catalyst, and sulfur or sodium thiosulfate are provided. The polyacrylonitrile is dissolved in the first solvent to form a polyacrylonitrile solution. The catalyst is uniformly dispersed in the polyacrylonitrile solution. The polyacrylonitrile solution with the catalyst is heated to induce a cyclizing reaction of the polyacrylonitrile, thereby forming a first conjugated polymer solution with a conjugated polymer. The sulfur or sodium thiosulfate is uniformly mixed with the conjugated polymer to form a mixture. The mixture is heated to form sulfurized polyacrylonitrile.

Abstract: The present disclosure relates to a method for making a conjugated polymer. In the method, polyacrylonitrile, a solvent, and a catalyst are provided. The polyacrylonitrile is dissolved in the solvent to form a polyacrylonitrile solution. The catalyst is uniformly dispersed into the polyacrylonitrile solution. The polyacrylonitrile solution with the catalyst is heated to induce a cyclizing reaction of the polyacrylonitrile, thereby forming a conjugated polymer solution with conjugated polymer.

Abstract: The present disclosure relates to a method for making a conjugated polymer. In the method, polyacrylonitrile, a solvent, and a catalyst are provided. The polyacrylonitrile is dissolved in the solvent to form a polyacrylonitrile solution. The catalyst is uniformly dispersed into the polyacrylonitrile solution. The polyacrylonitrile solution with the catalyst is heated to induce a cyclizing reaction of the polyacrylonitrile, thereby forming a conjugated polymer solution with the conjugated polymer dissolved therein.