Abstract: A method for producing a silicon material, the method including: a step of heating CaSi2 powder in a range of 400 to 1000° C.; a step of reacting acid with the CaSi2 powder having been subjected to the step of heating CaSi2 powder in a range of 400 to 1000° C., to obtain a layered silicon compound; and a step of heating the layered silicon compound at not less than 300° C.

Abstract: An active material expressed by a general formula; LiaNibCocMndDeOf (where 0.2?“a”?1, “b”+“c”+“d”+“e”=1, 0?“e”<1, “D” is at least one element selected from the group consisting of Li, Fe, Cr, Cu, Zn, Ca, Mg, Zr, S, Si, Na, K and Al, and 1.7?“f”?2.1) includes a high manganese portion, which is made of a metallic oxide including Ni, Co and Mn at least and of which the composition ratio between Ni, Co and Mn is expressed by Ni:Co:Mn=b2:c2:d2 (note that “b2”+“c2”+“d2”=1, 0<“b2”<1, 0<“c2”<“c”, and “d”<“d2”<1), in a superficial layer thereof.

Abstract: A lithium composite metallic oxide expressed by: LiaNibCocMndDeOf (where 0.2?“a”?1.5, “b”+“c”+“d”+“e”=1, 0<“e”<1, “D” is at least one of the following elements: Fe, Cr, Cu, Zn, Ca, Mg, Zr, S, Si, Na, K, Al, Ti, P, Ga, Ge, V, Mo, Nb, W, La, Hf and Rf, and 1.7?“f”?2.1), and including: a high manganese portion, which is made of a metallic oxide including Ni, Co and Mn at least and of which the composition ratio between Ni, Co and Mn is expressed by Ni:Co:Mn=g:h:i (note that “g”+“h”+“i”=1, 0<“g”<1, 0<“h”<“c”, and “d”<“i”<1), in a superficial layer thereof; and a metallic oxidation portion in an outermost superficial layer of the high manganese portion.

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 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: 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 novel silicon material is provided. An MSix-containing silicon material contains MSix (M is at least one element selected from the group 3 to 9 elements. 1/3?x?3) in a silicon matrix.

Abstract: An active material expressed by a general formula; LiaNibCocMndDeOf (where 0.2?“a”?1, “b”+“c”+“d”+“e”=1, 0?“e”<1, “D” is at least one element selected from the group consisting of Li, Fe, Cr, Cu, Zn, Ca, Mg, Zr, S, Si, Na, K and Al, and 1.7?“f”?2.1) includes a high manganese portion, which is made of a metallic oxide including Ni, Co and Mn at least and of which the composition ratio between Ni, Co and Mn is expressed by Ni:Co:Mn=b2:c2:d2 (note that “b2”+“c2”+“d2”=1, 0<“b2”<1, 0<“c2”<“c”, and “d”<“d2”<1), in a superficial layer thereof.

Abstract: A method for producing a silicon material, the method including: a step of heating CaSi2 powder in a range of 400 to 1000° C.; a step of reacting acid with the CaSi2 powder having been subjected to the step of heating CaSi2 powder in a range of 400 to 1000° C., to obtain a layered silicon compound; and a step of heating the layered silicon compound at not less than 300° C.

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: An active material expressed by a general formula; LiaNibCocMndDeOf (where 0.2?“a”?1, “b”+“c”+“d”+“e”=1, 0?“e”<1, “D” is at least one element selected from the group consisting of Li, Fe, Cr, Cu, Zn, Ca, Mg, Zr, S, Si, Na, K and Al, and 1.7?“f”?2.1) includes a high manganese portion, which is made of a metallic oxide including Ni, Co and Mn at least and of which the composition ratio between Ni, Co and Mn is expressed by Ni:Co:Mn=b2:c2:d2 (note that “b2”+“c2”+“d2”=1, 0<“b2”<1, 0<“c2”<“c”, and “d”<“d2”<1), in a superficial layer thereof.

Abstract: A novel silicon material is provided. An MSix-containing silicon material contains MSix (M is at least one element selected from the group 3 to 9 elements. 1/3?x?3) in a silicon matrix.

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 negative electrode active material having improved electron conductivity is provided. A reaction between an acid and a copper-containing calcium silicide represented by CaCuxSiy is caused, and a heat treatment is performed in a non-oxidizing atmosphere on the reaction product, to obtain a copper-containing silicon material. The copper-containing silicon material contains Si and copper in an amorphous phase, and fine copper silicide is uniformly deposited within the amorphous phase. Thus, electron conductivity improves. Therefore, a secondary battery in which the negative electrode active material is used as a negative electrode has improved rate characteristics and also has an increased charge/discharge capacity.

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: A lithium composite metallic oxide expressed by: LiaNibCocMndDeOf (where 0.2?“a”?1.5, “b”+“c”+“d”+“e”=1, 0<“e”<1, “D” is at least one of the following elements: Fe, Cr, Cu, Zn, Ca, Mg, Zr, S, Si, Na, K, Al, Ti, P, Ga, Ge, V, Mo, Nb, W, La, Hf and Rf, and 1.7?“f”?2.1), and including: a high manganese portion, which is made of a metallic oxide including Ni, Co and Mn at least and of which the composition ratio between Ni, Co and Mn is expressed by Ni:Co:Mn=g:h:i (note that “g”+“h”+“i”=1, 0<“g”<1, 0<“h”<“c”, and “d”<“i”<1), in a superficial layer thereof; and a metallic oxidation portion in an outermost superficial layer of the high manganese portion.

Abstract: An active material expressed by a general formula; LiaNibCocMndDeOf (where 0.2?“a”?1, “b”+“c”+“d”+“e”=1, 0?“e”<1, “D” is at least one element selected from the group consisting of Li, Fe, Cr, Cu, Zn, Ca, Mg, Zr, S, Si, Na, K and Al, and 1.7?“f”?2.1) includes a high manganese portion, which is made of a metallic oxide including Ni, Co and Mn at least and of which the composition ratio between Ni, Co and Mn is expressed by Ni:Co:Mn=b2:c2:d2 (note that “b2”+“c2”+“d2”=1, 0<“b2”<1, 0<“c2”<“c”, and “d”<“d2”<1), in a superficial layer thereof.

Abstract: Providing a positive-electrode active material for lithium-ion secondary battery, the positive-electrode active material contributing to upgrading the rate characteristic and cyclability, and providing a lithium-ion secondary battery including the same. The positive-electrode active material includes a positive-electrode active-material body, and an adhesion portion adhering on at least some of a surface of the positive-electrode active-material body. The adhesion portion is composed of a compound expressed by a chemical formula: (ZrO)2P2O7.

Abstract: An iron alloy according to the present invention comprises: Al in an amount of from 3 to 5.5%; Mn in an amount from 0.2 to 6%; and the balance being iron (Fe), and inevitable impurities and/or a modifying element; when the entirety is taken as 100%. Since a high damping factor is obtainable at a low-strain amplitude, this iron alloy demonstrates a stable damping property even in a high-temperature region. Moreover, since the alloying elements are Al and Mn alone, and since their contents are less, the iron alloy according to the present invention is low in cost.