Abstract: There is provided an electrode active material for a sodium secondary battery, containing Na and M1. Here, M1 is one or more elements selected from the group consisting of Si, Ge, Sn, Pb, Sb, and Bi, and a molar ratio (Na:M1) of Na to M1 is t:1, where t is a number of 2 or more and 3 or less.

Abstract: A positive electrode-active material is provided for use in a positive electrode for a sodium secondary cell and a sodium secondary cell. Also provided is a positive electrode for a sodium secondary cell and a sodium secondary cell having a high energy density. The positive electrode-active material for a sodium secondary cell includes a composite metal oxide, which has an ?-NaFeO2 type crystal structure and is denoted by Formula (1) described below: Naa(FewNixMny-zTiz)O2??(1), wherein a is greater than or equal to 0.6 and less than or equal to 1.0, w is greater than 0 and less than 0.5, x is greater than 0 and less than 0.5, y is greater than 0.03 and less than or equal to 0.5, z is greater than or equal to 0.03 and less than 0.5, and w+x+y=1.0, and y>z.

Abstract: The present invention provides a sodium secondary battery capable of reducing the amount of lithium used, and ensuring a larger discharge capacity maintenance rate when having repeated a charge and discharge, as compared with conventional techniques; and a mixed metal oxide usable as the positive electrode active material therefor. A mixed metal oxide of the present invention comprises Na and M1 wherein M1 represents three or more elements selected from the group consisting of Mn, Fe, Co and Ni with an Na:M1 molar ratio being a:1 wherein a is a value falling within the range of more than 0.5 and less than 1. Also, a mixed metal oxide of the present invention is represented by the following formula (1): NaaM1O2??(1) wherein M1 and a each have the same meaning as above. The positive electrode active material for secondary batteries of the present invention comprises the mixed metal oxide above.

Abstract: Disclosed is a mixed metal oxide comprising Na, M1, and M2, where M1 represents at least one element selected from the group consisting of Mg, Ca, Sr, and Ba; and M2 represents at least one element selected from the group consisting of Mn, Fe, Co, and Ni, wherein the molar ratio of Na:M1:M2 is a:b:1, where a is a value within the range of not less than 0.5 and less than 1; b is a value within the range of more than 0 and not more than 0.5; and “a+b” is a value within the range of more than 0.5 and not more than 1. An electrode having an active material containing the mixed metal oxide is also disclosed. Further disclosed is an electrode containing the electrode active material as well as a sodium secondary battery comprising the electrode as a positive electrode.

Abstract: A positive electrode-active material is provided for use in a positive electrode for a sodium secondary cell and a sodium secondary cell. Also provided is a positive electrode for a sodium secondary cell and a sodium secondary cell having a high energy density. The positive electrode-active material for a sodium secondary cell includes a composite metal oxide, which has an ?-NaFeO2 type crystal structure and is denoted by Formula (1) described below: Naa(FewNixMny-zTiz)O2??(1), wherein a is greater than or equal to 0.6 and less than or equal to 1.0, w is greater than 0 and less than 0.5, x is greater than 0 and less than 0.5, y is greater than 0.03 and less than or equal to 0.5, z is greater than or equal to 0.03 and less than 0.5, and w+x+y=1.0, and y>z.

Abstract: A sodium secondary battery capable of reducing the amount used of a scarce metal element such as lithium and cobalt and moreover, ensuring a larger discharge capacity after repeating charge/discharge as compared with conventional techniques, and a mixed metal oxide usable as the positive electrode active material therefor. The mixed metal oxide comprises Na, Mn and M1 wherein M1 is Fe or Ni, with a Na:Mn:M1 molar ratio being a:(1?b):b wherein a is a value falling within the range of more than 0.5 and less than 1, and b is a value falling within the range of from 0.001 to 0.5. Another mixed metal oxide is a mixed metal oxide represented by the following formula (1): NaaMn1?bM1bO2 (1) wherein M1, a and b each have the same meaning as above. The positive electrode active material for sodium secondary batteries comprises the mixed metal oxide above.

Abstract: Disclosed are a positive electrode active material and a method for producing an olivine-type phosphate. The positive electrode active material comprises an olivine-type phosphate represented by the following formula (I), wherein the maximum peak in an X-ray diffraction pattern obtained using a CuK? ray is the peak of the (031) plane of the olivine-type phosphate and the half-value width of the peak is 1.5° or less: AaMbPO4 (I), wherein A represents one or more elements selected from among alkali metals; M represents one or more elements selected from among transition metals; a is from 0.5 to 1.5; and b is from 0.5 to 1.5. The method for producing an olivine-type phosphate comprises preparing a raw material comprising element A, element M, and phosphorus (P) so that a A:M:P molar ratio may be a:b:1, preliminary calcining the raw material, and mainly calcining the preliminary calcined raw material.

Abstract: The present invention provides an electrode that can be used for a sodium secondary battery having a larger discharge capacity when charging and discharging are performed repeatedly than that of the prior art. This sodium secondary battery electrode contains tin (Sn) powder as an electrode active material. The electrode, particularly, further contains one or more electrode-forming agents selected from the group consisting of poly(vinylidene fluoride) (PVDF), poly(acrylic acid) (PAA), poly(sodium acrylate) (PAANa), and carboxymethylcellulose (CMC), thereby making it possible to provide a sodium secondary battery having even greater electrode performance.

Abstract: The present invention relates to a sodium secondary battery comprising a first electrode comprising a carbonaceous material which can be doped and dedoped with a sodium ion, a second electrode, and a non-aqueous electrolytic solution in which an electrolyte salt is dissolved in a non-aqueous solvent, wherein the non-aqueous electrolytic solution comprises a cyclic carbonate containing an unsaturated bond, a cyclic carbonate containing fluorine, or both, in the range of 0.01% by volume or more and 10% by volume or less relative to the non-aqueous electrolytic solution.

Abstract: Disclosed is a mixed metal oxide comprising Na, M1, and M2, where M1 represents at least one element selected from the group consisting of Mg, Ca, Sr, and Ba; and M2 represents at least one element selected from the group consisting of Mn, Fe, Co, and Ni, wherein the molar ratio of Na:M1:M2 is a:b:1, where a is a value within the range of not less than 0.5 and less than 1; b is a value within the range of more than 0 and not more than 0.5; and “a+b” is a value within the range of more than 0.5 and not more than 1. An electrode having an active material containing the mixed metal oxide is also disclosed. Further disclosed is an electrode containing the electrode active material as well as a sodium secondary battery comprising the electrode as a positive electrode.

Abstract: The present invention provides a sodium secondary battery. The sodium secondary battery includes a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and a nonaqueous electrolytic solution, the separator is composed of a porous laminate film in which a heat resistant porous layer and a porous film are stacked each other, and the heat resistant porous layer is disposed on the positive electrode side.

Abstract: The present invention provides a sodium secondary battery. The sodium secondary battery includes a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and a nonaqueous electrolytic solution, the separator is composed of a porous laminate film in which a heat resistant porous layer and a porous film are stacked each other, and the heat resistant porous layer is disposed on the negative electrode side.

Abstract: Disclosed are an electrode active material and a method for producing an electrode active material. The method for producing an electrode active material comprises the following steps (i), (ii) and (iii). (i) An aqueous solution containing M is brought into contact with a precipitant, thereby obtaining a precipitate, wherein M represents at least two elements selected from the group consisting of metal elements other than alkali metal elements. (ii) The precipitate is mixed with a sodium compound, thereby obtaining a mixture. (iii) The mixture is calcined.

Abstract: The present invention provides a sodium secondary battery having a superior cycling performance as compared with conventional techniques. A sodium secondary battery of the present invention comprises a positive electrode comprising a mixed metal oxide which comprises Na and M1 wherein M1 represents two or more elements selected from the group consisting of Mn, Fe, Co and Ni, with an Na:M1 molar ratio being a:1 wherein a is a value falling within the range of more than 0.5 and less than 1, a negative electrode comprising a carbonaceous material capable of storing and releasing Na ions, and an electrolyte. Further, the sodium secondary battery of the present invention may comprise a separator, and the separator may be a separator comprising a porous laminated film in which a heat-resistant porous layer comprising a heat-resistant resin and a porous film comprising a thermoplastic resin are stacked each other.

Abstract: The present invention provides a sodium secondary battery capable of reducing the amount used of a scarce metal element such as lithium and cobalt and moreover, ensuring a larger discharge capacity after repeating charge/discharge as compared with conventional techniques, and a mixed metal oxide usable as the positive electrode active material therefor. The mixed metal oxide of the present invention comprises Na, Mn and M1 wherein M1 is Fe or Ni, with a Na:Mn:M1 molar ratio being a:(1-b):b wherein a is a value falling within the range of more than 0.5 and less than 1, and b is a value falling within the range of from 0.001 to 0.5. Another mixed metal oxide of the present invention is a mixed metal oxide represented by the following formula (1): NaaMn1-bM1bO2 (1) wherein M1, a and b each have the same meaning as above. The positive electrode active material for sodium secondary batteries of the present invention comprises the mixed metal oxide above.

Abstract: The present invention provides a sodium secondary battery capable of reducing the amount of lithium used, and ensuring a larger discharge capacity maintenance rate when having repeated a charge and discharge, as compared with conventional techniques; and a mixed metal oxide usable as the positive electrode active material therefor. A mixed metal oxide of the present invention comprises Na and M1 wherein M1 represents three or more elements selected from the group consisting of Mn, Fe, Co and Ni with an Na:M1 molar ratio being a:1 wherein a is a value falling within the range of more than 0.5 and less than 1. Also, a mixed metal oxide of the present invention is represented by the following formula (1): NaaM1O2??(1) wherein M1 and a each have the same meaning as above. The positive electrode active material for secondary batteries of the present invention comprises the mixed metal oxide above.

Abstract: Disclosed are a positive electrode active material and a method for producing an olivine-type phosphate. The positive electrode active material comprises an olivine-type phosphate represented by the following formula (I), wherein the maximum peak in an X-ray diffraction pattern obtained using a CuK? ray is the peak of the (031) plane of the olivine-type phosphate and the half-value width of the peak is 1.5° or less: AaMbPO4 (I), wherein A represents one or more elements selected from among alkali metals; M represents one or more elements selected from among transition metals; a is from 0.5 to 1.5; and b is from 0.5 to 1.5. The method for producing an olivine-type phosphate comprises preparing a raw material comprising element A, element M, and phosphorus (P) so that a A:M:P molar ratio may be a:b:1, preliminary calcining the raw material, and mainly calcining the preliminary calcined raw material.

Abstract: Disclosed is a mixed metal oxide which is reduced in the amount of scarce metal used therein, while having excellent performance as a positive electrode active material for secondary batteries. Also disclosed are a positive electrode for sodium secondary batteries having excellent performance, and a sodium secondary battery. Specifically disclosed is a method for producing a sodium-manganese complex metal oxide which is characterized by comprising a step for calcining a material, which contains sodium carbonate (Na2CO3) and dimanganese trioxide (Mn2O3) in such amounts that the molar ratio of sodium to manganese (Na/Mn) is not less than 0.4 but not more than 0.7, at a temperature of not less than 850° C. Also specifically disclosed are a sodium-manganese complex metal oxide produced by the method, a positive electrode for sodium secondary batteries which contains such a sodium-manganese complex metal oxide, and a sodium secondary battery.

Abstract: Disclosed is a mixed metal oxide which is extremely useful as a positive electrode active material for secondary batteries, while being reduced in the amount of a scarce metal used therein. Also disclosed are a positive electrode for sodium secondary batteries, and a sodium secondary battery. Specifically disclosed is a mixed metal oxide having an ?-NaFeO2 type (layered rocksalt-type) crystal structure and represented by the following formula: NaxFe1-yMyO2 (wherein M represents one or more elements selected from the group consisting of group 4 elements, group 5 elements, group 6 elements and group 14 elements of the IUPAC periodic table and Mn; x represents a value more than 0.5 but less than 1; and y represents a value more than 0 but less than 0.5). Also specifically disclosed are a positive electrode for sodium secondary batteries, which contains the mixed metal oxide, and a sodium secondary battery.

Abstract: Disclosed are a phosphor having high luminance, a phosphor paste containing the phosphor and a light-emitting device. The phosphor includes an oxide containing M1, M2 and M3 (wherein M1 represents at least one element selected from the group consisting of Ba, Sr and Ca; M2 represents at least one element selected from the group consisting of Ti, Zr, Hf, Si, Ge and Sn, while containing at least Sn; and M3 represents at least one element selected from the group consisting of Si and Ge) as a base material, while being added with an activator.