Osaka Titanium Technologies Co., Ltd.

Yusuke Kashitani

Shingo Kizaki

Kohki Takeshita

Takehisa Fujita

[Problem to be solved] To produce an SiO powder having a rounded spherical particulate shape and a small particle diameter; and further having a low degree of impurity contamination, efficiently and economically. [Solution] A mixture of Si and SiOas an SiO gas generation raw materialis loaded into a crucible. The mixture in the crucibleis heated under a reduced pressure so as to generate SiO gas. The generated SiO gas is accumulated on a deposition baserotating on the crucible. When SiO depositaccumulated on the deposition baseis scraped off with a blade, a tip of the bladeis separated from a surface of the deposition base, and in a state in which a portion of the SiO depositaccumulated on the deposition baseis left on the deposition base, the remaining SiO depositis scraped off by the bladeand collected as an SiO powder

SiO powder production method and spherical particulate SiO powder

In a method for continuously generating silicon monoxide (SiO) gas, wherein a silicon monoxide gas-generating raw material in a raw material supply unit is continuously charged into a reaction chamber RM, an inert gas is flowed through the raw material supply unit so as to be directed toward the charging direction of the silicon monoxide gas-generating raw material. The method for continuously generating silicon monoxide gas prevents a decrease in yield of the silicon monoxide (SiO) gas-generating raw material.

Method for continuously generating silicon monoxide gas

To produce a silicon oxide-based negative electrode material containing Li and having uniform distribution of a Li concentration both inside particles and between particles although a C-coating film is formed on a surface, and yet in which generation of SiC is suppressed. A SiO gas and a Li gas are simultaneously generated by heating a Si-lithium silicate-containing raw material under reduced pressure. The Si-lithium silicate-containing raw material includes Si, Li, and O, in which a part of the Si is present as a Si simple substance and the Li is present as lithium silicate. By cooling the generated gases, Li-containing silicon oxide having an average composition of SiLiO(0.05&#x3c;x&#x3c;y and 0.5&#x3c;y&#x3c;1.5 are satisfied) is prepared. After adjusting the particle size, a C-coating film having an average film thickness of 0.5 to 10 nm is formed on a surface of particles at a treatment temperature of 900&#xb0; C. or less.

Method for producing silicon oxide powder and negative electrode material

[Problem] Provided is a silicon oxide-based negative electrode material capable of avoiding, as much as possible, decreased battery performance resulting from a heterogeneous distribution of a Li concentration. [Solution] Provided is a powder having an average composition of SiLiOwherein 0.05&#x3c;x&#x3c;y&#x3c;1.2 and a mean particle size of 1 &#x3bc;m or more. Further, 10 particles randomly selected from particles of the powder each satisfy 0.8&#x3c;L1/L2&#x3c;1.2 with the standard deviation of L2 being 0.1 or less, L1 being a Li concentration at a depth of 50 nm from an outermost surface of each of the 10 particles, and L2 being a Li concentration at a depth of 400 nm from the outermost surface.

Lithium doped silicon oxide-based negative electrode material and method of manufacturing the same

There is produced a Li-containing silicon oxide powder containing a crystallized lithium silicate that is mostly water-insoluble LiSiOand containing little crystalline Si. This object is attained through the mixing of a lower silicon oxide powder represented by a compositional formula SiO(0.5&#x3c;x&#x3c;1.5) with a powdered lithium source that involves grinding of the powdered lithium source; controlling a median diameter D1 of the lower silicon oxide powder and a median diameter D2 of the powdered lithium source so as to fulfill 0.05&#x2264;D2/D1&#x2264;2; and calcining the mixed powder at 300&#xb0; C. or higher and 800&#xb0; C. or lower.

Li-containing silicon oxide powder and production method thereof

This invention provides a powder for a negative electrode of a lithium ion secondary battery, which is a powder that includes a silicon oxide powder containing Li. When a molar ratio between Li, Si and O is taken as y:1:x, the average composition of the powder overall satisfies the relation 0.5&#x3c;x&#x3c;1.5 and the relation 0.1&#x3c;y/x&#x3c;0.8. The volume median diameter of the powder for a negative electrode is within a range from 0.5 to 30 &#x3bc;m. When X-ray diffraction measurement of the powder is performed using a Cu Kray, a relation P2/P1&#x2264;1.0 and a relation P3/P1&#x2264;1.0 are satisfied, where P1 represents a height of a peak attributed to LiSiO, P2 represents a height of a peak attributed to crystalline Si, and P3 represents a height of a peak attributed to LiSiO.

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Amagasaki, Japan

Yusuke Kashitani