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: 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 current collector includes a metal foil and a graphene film coated on a surface of the current collector. An electrode of an electrochemical battery includes the current collector and an electrode active material layer coated on a surface of the current collector. An electrochemical battery is also provided which including the electrode.

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: The present disclosure relates to a piezoelectric sensor. The piezoelectric sensor includes a polymer layer, a first metal layer, and a second metal layer. The polymer layer includes pyrolytic polyacrylonitrile. The first metal layer is located on a surface of the polymer layer. The first metal layer includes a first work function. The second metal layer is located on another surface of the polymer layer and includes a second work function different from the first work function. The present disclosure also relates to a method for making the piezoelectric sensor.

Abstract: A phosphorated polymer includes a conductive polymer main-chain and a side-chain connected to the conductive polymer main-chain. The side-chain includes an electrochemically active phosphorated group Pm. A method for making the phosphorated polymer and a lithium-ion battery using the phosphorated polymer is also provided.

Abstract: A lithium-ion battery includes an anode, a cathode, and an electrolyte. The anode includes a phosphorated composite including a conductive matrix and a red phosphorus. The conductive matrix includes a material being selected from the group consisting of conductive polymer and conductive carbonaceous material. A weight percentage of the conductive matrix in the phosphorated composite ranges from about 10% to about 85%. A weight percentage of the red phosphorus in the phosphorated composite ranges from about 15% to about 90%.

Abstract: An electrode composite material includes an individual electrode active material particle and a protective film coated on a surface of the particle. A composition of the protective film is AlxMyPO4, AlxMy(PO3)3, or a combination thereof. M represents at least one of Cr, Zn, Mg, Zr, Mo, V, Nb, or Ta. A valence of M is represented by k, in which 0<x<1, 0<y<1, and 3x+ky=3. In addition, a molar ratio of an aluminum element, an M element, and a phosphorous element in AlxMyPO4 or AlxMy(PO3)3 is set by (MolAl+MolMetal):Molp equal to about 1:2.5 to about 1:4, MolAl is the amount of substance of the aluminum element, MolMetal is the amount of substance of the M element, and Molp is the amount of substance of the phosphorous element. A lithium ion battery includes the electrode composite material.

Abstract: A method for making a modified current collector of a lithium ion battery is provided. In the method, the modifier and a metal plate are provided. The modifier is a mixture of a phosphorus source having a phosphate radical, a trivalent aluminum source, and a metallic oxide provided in a liquid phase solvent. The modifier is coated on a surface of the metal plate to form a coating layer. The coated metal plate is heat treated to transform the coating layer into a protective film formed on the surface of the metal plate.

Abstract: A modified current collector includes a metal plate and a protective film disposed on a surface of the metal plate. A composition of the protective film is at least one of AlxMyPO4 and AlxMy(PO3)3. M represents at least one chemical element selected from the group consisting of Cr, Zn, Mg, Zr, Mo, V, Nb, and Ta. A valence of M is represented by k, wherein 0<x<1, 0<y<1, and 3x+ky=3.

Abstract: An electrode composite material includes an individual electrode active material particle and a protective film coated on a surface of the particle. A composition of the protective film is AlxMyPO4, AlxMy(PO3)3, or a combination thereof. M represents at least one of Cr, Zn, Mg, Zr, Mo, V, Nb, or Ta. A valence of M is represented by k, in which 0<x<1, 0<y<1, and 3x+ky=3. In addition, a molar ratio of an aluminum element, an M element, and a phosphorous element in AlxMyPO4 or AlxMy(PO3)3 is set by (MolAl+MolMetal):Molp equal to about 1:2.5 to about 1:4, MolAl is the amount of substance of the aluminum element, MolMetal is the amount of substance of the M element, and Molp is the amount of substance of the phosphorous element. A lithium ion battery includes the electrode composite material.

Abstract: An electrode composite material includes an individual electrode active material particle and a protective film coated on a surface of the particle. A composition of the protective film is at least one of AlxMyPO4 and AlxMy(PO3)3, M represents at least one chemical element selected from the group consisting of Cr, Zn, Mg, Zr, Mo, V, Nb, and Ta, and a valence of M is represented by k, wherein 0<x<1, 0<y<1, and 3x+ky=3.

Abstract: A method for making a separator of a lithium ion battery is provided. In the method, a modifier, and a porous membrane are provided. The modifier is a mixture of a phosphorus source having a phosphate radical, a trivalent aluminum source, and a metallic oxide provided in a liquid phase solvent. The modifier is coated on a surface of the porous membrane to form a coating layer. The coated porous membrane is dried to form a modifier layer disposed on the surface of the porous membrane.

Abstract: A separator of a battery includes a porous membrane and a modifier layer disposed on a surface of the porous membrane, wherein a material of the modifier layer is a dried mixture of a phosphorus source having a phosphate radical, a trivalent aluminum source, and a metallic oxide in a liquid phase solvent.

Abstract: A modified current collector includes a metal plate and a protective film disposed on a surface of the metal plate. A composition of the protective film is at least one of AlxMyPO4 and AlxMy(PO3)3. M represents at least one chemical element selected from the group consisting of Cr, Zn, Mg, Zr, Mo, V, Nb, and Ta. A valence of M is represented by k, wherein 0<x<1, 0<y<1, and 3x+ky=3.

Abstract: An electrode composite material includes an individual electrode active material particle and a protective film coated on a surface of the particle. A composition of the protective film is at least one of AlxMyPO4 and AlxMy(PO3)3, M represents at least one chemical element selected from the group consisting of Cr, Zn, Mg, Zr, Mo, V, Nb, and Ta, and a valence of M is represented by k, wherein 0<x<1, 0<y<1, and 3x+ky=3.

Abstract: A separator of a battery includes a porous membrane and a modifier layer disposed on a surface of the porous membrane, wherein a material of the modifier layer is a dried mixture of a phosphorus source having a phosphate radical, a trivalent aluminum source, and a metallic oxide in a liquid phase solvent.

Abstract: The present disclosure relates to a method for making an electrode material of lithium-ion batteries. In the method, a lithium source solution and a plurality of titanium source particles are provided. The lithium source solution and the titanium source particles are mixed, wherein a molar ratio of lithium element to titanium element is in a range from about 4:5 to about 9:10, thereby forming a sol. A carbon source compound is dispersed into the sol to form a sol mixture. The sol mixture is spray dried to form a plurality of precursor particles. The precursor particles are heated to form a lithium titanate composite electrode material.

Abstract: The present disclosure relates to a method for making an electrode material of lithium-ion batteries. In the method, a carbon source compound is dissolved into a solvent to form a liquid phase solution. A number of titanium dioxide particles are provided and are dispersed into the liquid phase solution. The carbon source compound is pyrolyzed, thereby forming a number of carbon coating titanium dioxide particles. A lithium source solution is provided. The lithium source solution and the carbon coating titanium dioxide particles are mixed, according to a molar ratio in a range from about 4:5 to about 9:10, of lithium element to titanium element, thereby forming a sol. The sol is spray dried to form a number of precursor particles. The precursor particles are heated to form a lithium titanate composite electrode material.

Abstract: The present disclosure relates to a piezoelectric sensor. The piezoelectric sensor includes a polymer layer, a first metal layer, and a second metal layer. The polymer layer includes pyrolytic polyacrylonitrile. The first metal layer is located on a surface of the polymer layer. The first metal layer includes a first work function. The second metal layer is located on another surface of the polymer layer and includes a second work function different from the first work function. The present disclosure also relates to a method for making the piezoelectric sensor.