Abstract: Provided is a method for producing a silicon material, the method including: a molten metal preparing step of preparing Ca-x at % Si alloy (42?x?75) molten metal; a solidifying step of cooling the molten metal by a rapid cooling device to solidify the Ca-x at % Si alloy; a synthesizing step of reacting the solidified Ca-x at % Si alloy with acid to obtain a layered silicon compound; and a heating step of heating the layered silicon compound at not less than 300° C.

Abstract: Provided is a method for producing a CaSi2-containing composition, the method including: a molten metal step of adding Ca and/or M (M is at least one element selected from elements of groups 3 to 9) to a CaSi2-containing composition containing crystalline silicon to prepare a molten metal containing Ca, M and Si that satisfy the following condition: when a molar ratio of Ca, M and Si is x:y:z (x+y+z=100), x, y and z satisfy 23<x?100/3, 0<y<10 and 64<z?200/3, respectively; and a cooling step of cooling the molten metal to obtain a CaSi2-containing composition containing a reduced amount of crystalline silicon.

Abstract: A polymer compound for use as a binder for a negative electrode of an electrical storage device is formed by condensing polyacrylic acid and a multifunctional amine represented by the following formula (1), in which Y represents a straight chain alkyl group having 1 to 4 carbon atoms, a phenylene group, or an oxygen atom, and R1 and R2 each independently represent one or more hydrogen atoms, methyl groups, ethyl groups, trifluoromethyl groups, or methoxy groups.

Abstract: Providing a silicon-containing material having a novel structure being distinct from the structure of conventional silicon oxide disproportionated to use. A silicon-containing material according to the present invention includes at least the following: a continuous phase including silicon with Si—Si bond, and possessing a bubble-shaped skeleton being continuous three-dimensionally; and a dispersion phase including silicon with Si—O bond, and involved in an area demarcated by said continuous phase to be in a dispersed state.

Abstract: A polymer compound, which is used as a binder for a negative electrode of an electricity storage device, is obtained by condensation of a vinyl polymer that contains a carboxyl group and a third compound that is selected from among an aromatic multifunctional amine, phosphorous acid, phosphorous acid ester, trialkoxysilane, and phosphoric acid.

Abstract: A polymer compound for use as a binder for a negative electrode of an electrical storage device is formed by condensing polyacrylic acid and a multifunctional amine represented by the following formula (1), in which Y represents a straight chain alkyl group having 1 to 4 carbon atoms, a phenylene group, or an oxygen atom, and R1 and R2 each independently represent one or more hydrogen atoms, methyl groups, ethyl groups, trifluoromethyl groups, or methoxy groups.

Abstract: A production process for carbon-coated silicon material includes the step of: heating CaSi2 and a halogen-containing polymer at a temperature being a carbonization temperature or more of the halogen-containing polymer in a state where the CaSi2 and the halogen-containing polymer coexist.

Abstract: A production process for carbon-coated silicon material includes the steps of: a lamellar-silicon-compound production step of reacting CaSi2 with an acid to turn the CaSi2 into a lamellar silicon compound; a silicon-material production step of heating the lamellar silicon compound at 300° C. or more to turn the lamellar silicon compound into a silicon material; a coating step of coating the silicon material with carbon; and a washing step of washing the silicon material, or another silicon material undergone the coating step, with a solvent of which the relative permittivity is 5 or more.

Abstract: A silicon material useful as a negative electrode active material is provided. The silicon material has a band gap within a range of greater than 1.1 eV and not greater than 1.7 eV. A secondary battery in which this silicon material is used as a negative electrode active material has improved initial efficiency.

Abstract: A nano silicon material having reduced amounts of oxygen (O) and chlorine (Cl) contained therein is provided. The nano silicon material contains fluorine (F) and nano-sized silicon crystallites. Generation of a layer in which oxygen (O) and chlorine (Cl) are present is suppressed due to the presence of fluorine (F), so that a decrease in the moving speed of lithium ions is suppressed. In addition, due to the presence of fluorine (F), the concentrations of oxygen (O) and chlorine (Cl) are reduced, so that reaction thereof with lithium ions is suppressed.

Abstract: A silicon material useful as a negative electrode active material is provided. The silicon material has an Si/O atom ratio within a range of greater than 1/0.5 and not greater than 1/0.1 and a band gap within a range of greater than 1.1 eV and not greater than 2.1 eV. A secondary battery in which this silicon material is used as a negative electrode active material has long life.

Abstract: Provided is a negative electrode for a nonaqueous secondary battery which achieves both suppression of reductive decomposition of an electrolyte or an electrolytic solution and suppression of an increase in resistance. Also provided are a method for producing such a negative electrode and a nonaqueous secondary battery employing such a negative electrode. A polymer coating layer is formed so as to coat at least part of surfaces of negative electrode active material particles containing silicon oxide (SiOx; 0.5?x?1.6). The polymer coating layer contains a cationic polymer having a positive zeta potential under neutral conditions. Since silicon oxide has a negative zeta potential, a thin uniform coating layer can be formed owing to Coulomb's force.

Abstract: Provided is a negative electrode active material including complex particles formed of: nano silicon aggregated particles produced by heating a layered polysilane represented by a composition formula of (SiH)n and having a structure in which multiple six-membered rings formed from silicon atoms are connected; and a composited carbon layer formed from an amorphous carbon and at least covering one portion of the aggregated particles. A mean particle diameter D50 of the aggregated particles is within a range of 0.2 ?m to 30 ?m, and a mean particle diameter D50 of the complex particles is within a range of 0.5 ?m to 40 ?m.

Abstract: Cycle characteristics of a nonaqueous secondary battery are to be improved. An active material including: a first active material that contains a nano silicon produced by heating a layered polysilane represented by a composition formula (SiH)n and having a structure in which multiple six-membered rings formed from silicon atoms are connected; and a second active material that contains a graphite, is used in a negative electrode. With this, expansion and contraction due to stress during charging and discharging can be mitigated, and thereby cycle characteristics improve.

Abstract: An object is to provide a nonaqueous electrolyte secondary battery that has an SEI coating with a special structure and has excellent battery characteristics. As an electrolytic solution of the nonaqueous electrolyte secondary battery, an electrolytic solution containing: a salt whose cation is an alkali metal, an alkaline earth metal, or aluminum and whose cation is an alkali metal, an alkaline earth metal, or aluminum; and an organic solvent having a heteroelement is used, wherein, Is>Io is satisfied, and an S,O-containing coating having an S?O structure is formed on the surface of a positive electrode and/or a negative electrode. Alternatively, the above described electrolytic solution is used, and, as a binding agent for negative electrodes, a binding agent formed of a polymer having a hydrophilic group is used.

Abstract: To provide a nonaqueous electrolyte secondary battery that suppresses elution of Al from a positive electrode current collector formed of aluminum or an aluminum alloy, and is superior in thermal characteristics and input-output characteristics. Provided is a nonaqueous electrolyte secondary battery including a positive electrode, a negative electrode, and an electrolytic solution. The positive electrode has a positive electrode current collector formed of aluminum or an aluminum alloy. The electrolytic solution contains a metal salt and an organic solvent having a heteroelement. Regarding an intensity of a peak derived from the organic solvent in a vibrational spectroscopy spectrum of the electrolytic solution, Is>Io is satisfied when an intensity of an original peak of the organic solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is.

Abstract: To improve battery characteristics by an optimum combination of an electrolytic solution and a negative electrode active material. An electrolytic solution of a nonaqueous electrolyte secondary battery contains a metal salt, and an organic solvent having a heteroatom and satisfying, regarding an intensity of a peak derived from the organic solvent in a vibrational spectroscopy spectrum, Is>Io, when an intensity of an original peak of the organic solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is. As a negative electrode, any of the following (1) to (5) is used: (1) a graphite whose G/D ratio, which is a ratio of G-band and D-band peaks in a Raman spectrum, is not lower than 3.

Abstract: Provided is an electrolytic solution in which a metal salt and a solvent exist in a new state. The electrolytic solution of the present invention is an electrolytic solution containing a salt whose cation is an alkali metal, an alkaline earth metal, or aluminum, and an organic solvent having a heteroelement. Regarding an intensity of a peak derived from the organic solvent in a vibrational spectroscopy spectrum of the electrolytic solution, Is>Io is satisfied when an intensity of an original peak of the organic solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is.

Abstract: A positive electrode of a nonaqueous secondary battery has a positive electrode active material including at least one selected from lithium metal complex oxides having a layered rock salt structure, lithium metal complex oxides having a spinel structure, and polyanion based materials. The electrolytic solution contains a metal salt whose cation is an alkali metal, an alkaline earth metal, or aluminum, and an organic solvent having a heteroelement. Regarding an intensity of a peak derived from the organic solvent in a vibrational spectroscopy spectrum of the electrolytic solution, when an intensity of an original peak of the organic solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is; Is>Io is satisfied. The nonaqueous secondary battery may have a usage maximum potential of the positive electrode of not lower than 4.5 V when Li/Li+ is used for reference potential.

Abstract: A negative-electrode active material includes a mixed power of a first active-material powder composed of a granular graphite particle, and a second active-material powder composed of a plate-shaped graphite particle having a thickness of from 0.3 nm to 100 nm and a major-axis-direction length of from 0.1 ?m to 500 ?m. Since the plate-shaped graphite particle has a lam liar structure, the plate-shaped graphite particle excels in the strength and flexibility, and function as a negative-electrode active material because lithium ions come in and out between the layers. Therefore, while securing the flexibility of negative-electrode active-material layer, the contradictory event between the capacity and the conductive property is solved.