Abstract: A non-aqueous battery comprising a positive electrode material capable of being doped with and liberating lithium, a negative electrode material capable of being doped with and liberating lithium, and a polymer electrolyte disposed between the positive and negative electrode materials. The polymer electrolyte is formed by mixing a vinylidene fluoride copolymer and a nonaqueous electrolytic solution with a solvent, followed by evaporation of the solvent, so as to retain a high proportion of the nonaqueous electrolytic solution, leading to high electroconductivity and excellent strength in this state. The vinylidene fluoride copolymer comprises 80 to 97 wt. % of vinylidene fluoride monomer units and 3 to 20 wt. % of units of at least one monomer copolymerizable with vinylidene fluoride monomer, and has an inherent viscosity of 1.7 to 7 dl/g, as measured at 30° C. in a solution at a concentration of 4 g of polymer in 1 liter of N,N-dimethylformamide.

Abstract: A method for producing a vinylidene fluoride based polymer powder having a high molecular weight and excellent solubility in an organic solvent, which is useful as an electrode binder for nonaqueous cells, is provided. Methods for producing an NMP solution and an electrode mixture are also provided. A vinylidene fluoride based polymer powder produced by supercritical suspension polymerization in an aqueous dispersion medium wherein a volume of pores having a pore diameter of 0.03 ?m to 1.0 ?m, as measured by a mercury porosimeter, is 77 vol % to 93 vol % of a total pore volume and an inherent viscosity is 2.0 dl/g or greater is obtained.

Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 90 to 97 wt. % of vinylidene fluoride monomer units and 3 to 10 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.

Abstract: A process for producing a polymer electrolyte for a nonaqueous battery by mixing a vinylidene fluoride copolymer and a nonaqueous electrolytic solution with a solvent that can be evaporated, wherein the vinylidene fluoride copolymer comprises 80 to 97 wt. % of vinylidene fluoride monomer units and 3 to 20 wt % of units of at least one monomer copolymerizable with vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g, and evaporating the solvent to form a polymer electrolyte comprising the vinylidene fluoride copolymer impregnated with the nonaqueous electrolytic solution.

Abstract: A method for producing a vinylidene fluoride based polymer powder having a high molecular weight and excellent solubility in an organic solvent, which is useful as an electrode binder for nonaqueous cells, is provided. Methods for producing an NMP solution and an electrode mixture are also provided. A vinylidene fluoride based polymer powder produced by supercritical suspension polymerization in an aqueous dispersion medium wherein a volume of pores having a pore diameter of 0.03 ?m to 1.0 ?m, as measured by a mercury porosimeter, is 77 vol % to 93 vol % of a total pore volume and an inherent viscosity is 2.0 dl/g or greater is obtained.

Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 90 to 97 wt. % of vinylidene fluoride monomer units and 3 to 10 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.

Abstract: A process for producing a polymer electrolyte for a nonaqueous battery by introducing 80 to 97 wt. % of vinylidene fluoride monomer and 3 to 20 wt % of at least one monomer copolymerizable with vinylidene fluoride monomer simultaneously all at once into a polymerization vessel, polymerizing the monomers to provide a vinylidene fluoride copolymer having polymerized units of the monomers and having an inherent viscosity of 1.5 to 10 dl/g, and impregnating the vinylidene fluoride copolymer with a nonaqueous electrolytic solution to provide a polymer electrolyte.

Abstract: As a polymer composition for electrical wire coating is provided a vinylidene fluoride polymer composition, which has such heat-resistance as to withstand the heat generated from a wire in service and exhibits satisfactory flexibility even after the change with the passage of time. The polymer composition for electrical wire coating comprises a vinylidene fluoride copolymer and a vinylidene fluoride homopolymer. The preferable compounding ratio in the polymer composition is in the range of 20 to 80% by weight of a vinylidene fluoride copolymer and 80 to 20% by weight of a vinylidene fluoride homopolymer. The vinylidene fluoride copolymer is preferably one comprising 95 to 70% by weight of vinylidene fluoride and 5 to 30% by weight of a monomer copolymerizable with vinylidene fluoride.

Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 80 to 97 wt. % of vinylidene fluoride monomer units and 3 to 20 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.

Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 90 to 97 wt. % of vinylidene fluoride monomer units and 3 to 10 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.

Abstract: A vinylidene fluoride polymer having good high-temperature coloring resistance is produced through suspension polymerization at 10-100° C. in a mixture solvent of 100 wt. parts of an aqueous medium and 10-50 wt. parts of a halogenated hydrocarbon solvent showing a good dissolving power to both a vinylidene fluoride monomer and a polymerization initiator and represented by a formula of: CX3CX2CHX2, wherein X is a fluorine or chlorine atom, and 7 X's include 4-6 fluorine atoms and 1-3 chlorine atoms. The vinylidene fluoride polymer is characterized by an elutable total organic carbon content in pure water at 95° C. of at most 1.1 &mgr;g/cm2.

Abstract: A vinylidene fluoride polymer having good high-temperature coloring resistance is produced through suspension polymerization at 10-100° C. in a mixture solvent of 100 wt. parts of an aqueous medium and 10-50 wt.

Abstract: A solid polymer electrolyte having improved ionic conductivity and adhesion with an electroconductive substrate and also remarkably enhanced heat resistance is formed with a vinylidene fluoride copolymer which contains 50-97 mol. % of vinylidene fluoride monomer and 0.1-5 mol. % of an unsaturated dibasic acid monoester or an epoxy group-containing vinyl monomer and further has been crosslinked, thereby improving the performances of a non-aqueous battery, such as a lithium ion battery.

Abstract: A vinylidene fluoride polymer binder solution for forming an electrode for a non-aqueous-type battery is formed by adding an acid, preferably an organic acid, as a stabilizer to a solution of a vinylidene fluoride polymer in an organic solvent. The acid is preferably added in an amount sufficient to ensure a pH of at most 9 when measured with respect to a 10-times dilution of the binder solution with deionized water. The acid addition is effective for preventing a problematic viscosity increase in the binder solution and also gelling of an electrode-forming composition formed by adding a powdery electrode material in the binder solution.

Abstract: A binder solution for providing an electrode suitable for use in non-aqueous-type electrochemical devices, such as a battery and an electric double layer capacitor, is formed by dissolving a vinylidene fluoride polymer having an inherent viscosity (and thus a polymerization degree) higher than a conventional level in an organic solvent. An electrode-forming composition is formed by dispersing powdery electrode material in the binder solution and is applied onto an electroconductive substrate while avoiding the gelation of the polymer, followed by drying, to form a composite electrode layer, which retains the powdery electrode material at a smaller amount of vinylidene fluoride polymer than a conventional level and is well resistant to a non-aqueous electrolytic solution.

Abstract: A vinylidene fluoride copolymer having a relatively high molecular weight is formed by copolymerizing (a) vinylidene fluoride as a principal component, (b) a small amount of epoxy group-containing monomer, and (c) an optional component, such as an unsaturated dibasic acid monoester functioning as a curing agent for the epoxy group. When cured with an optional epoxy curing agent, the vinylidene fluoride copolymer provides a cured product having an adhesion with a metal substrate, etc., and also showing excellent solvent resistance and chemical resistance. The vinylidene fluoride copolymer is particularly suitable for constituting a binder for producing an electrode for a non-aqueous solvent-type secondary battery.

Abstract: This invention provides PVDF having such crystallization properties as to produce small spherulite sizes without sacrifices to properties, processability, purity, etc., and a suspension polymerization method to obtain the same.The PVDF obtained by this invention comprises the monomer unit content of 99.5-96 wt. % of vinylidene fluoride, and the monomer unit content of 0.5-4 wt. % of comonomers selected from hexafluoropropylene and/or tetrafluoroethylene, and has a logarithmic viscosity of 0.9-1.3 dl/g, and a molecular-weight distribution, as expressed in the ratio (Mw/Mn) of weight-average molecular weight and number-average molecular weight, of 2.2-2.8.In order to manufacture the PVDF of this invention, a mixture of vinylidene fluoride monomers containing 1-5 wt. % of monomers selected from hexafluoropropylene and/or tetrafluoroethylene is suspension-polymerized in an aqueous medium, using an oil-soluble initiator so that the logarithmic viscosity [.eta..sub.1 ] is kept at 1.3-1.

Abstract: Polyvinylidene fluoride (PVDF) having such crystallization properties as to produce small spheralite sizes without sacrificing properties, processability, purity, etc. comprises 99.5-96 wt. % of vinylidene fluoride and 0.5-4 wt. % of a comonomer selected from the group consisting of hexafluoropropylene, tetrafluoroethylene and mixtures thereof, has a logarithmic viscosity of 0.9-1.3 dl/g and a molecular weight distribution, as expressed by the ratio of weight average molecular weight to number average molecular weight, of 2.2-2.8. The PVDF is formed by suspension polymerizing vinylidene fluoride and 1-5 wt. % of the desired comonomer, in an aqueous medium in the presence of an oil-soluble initiator, so that a logarithmic viscosity [.eta..sub.1 ] of 1.3-1.9 dl/g is obtained at a vinylidene fluoride conversion of 10-50%; then adding a chain transfer agent to the medium and continuing polymerization so that the logarithmic viscosity [.eta..sub.2 ] of the final polymer is 0.3-0.7 dl/g lower than [.eta..sub.