Shin-etsu Chemical Co., Ltd.

Kohta Takahashi

Takakazu Hirose

Takumi Matsuno

Masahiro Furuya

Hiroki Yoshikawa

Hiromichi Kamo

Reiko Sakai

Yusuke Osawa

Hidekazu Awano

Koichiro Watanabe

Katsunori Nishiura

Yoshiyasu Yamada

Nan Fang

A negative electrode active material including negative electrode active material particles, wherein the negative electrode active material particles contain silicon compound particles containing a silicon compound, the silicon compound particles contain LiSiO, at least a part of a surface of the silicon compound particles is covered with a carbon layer, and a surface layer of the negative electrode active material particles contains a substance having a carboxylic acid structure. Provided by this configuration is a negative electrode active material capable of increasing battery capacity due to improved initial efficiency and capable of realizing satisfactory battery cycle characteristics.

Negative electrode active material, negative electrode and method for producing them

A negative electrode active material for a non-aqueous electrolyte secondary battery containing a negative electrode active material particle which includes a silicon compound particle containing a silicon compound (SiO: 0.5≤x≤1.6). The silicon compound particle contains a Li compound, at least a part of the silicon compound particle is coated with a carbon material, and at least a part of a surface of the silicon compound particle, a surface of the carbon material, or both of them is coated with a layer containing a compound having a silyl group.

Negative electrode active material for non-aqueous electrolyte secondary battery, non-aqueous electrolyte secondary battery, and method for producing negative electrode material for non-aqueous electrolyte secondary battery

A negative electrode active material containing negative electrode active material particles. The negative electrode active material particles include silicon compound particles each containing an oxygen-containing silicon compound. The silicon compound particle contains at least one of LiSiOand LiSiO. The silicon compound particle has, in a Si K-edge spectrum obtained from a XANES spectrum: a peak P derived from the Li silicate and located near 1847 eV; and a peak Q gentler than the peak P and located near 1851 to 1852 eV. This provides a negative electrode active material that is capable of stabilizing a slurry when the negative electrode active material is used for a secondary battery, and capable of increasing the battery capacity by improving the initial efficiency.

Negative electrode active material and method for producing the same

The inventive negative electrode active material for a non-aqueous electrolyte secondary battery contains negative electrode active material particles which include silicon compound (SiO: 0.5≤x≤1.6) particles. The negative electrode active material particles are at least partially coated with a carbon material, contain one or more selected from LiSiOand LiSiO, and satisfy Ib/Ia≤4.8 and Ic/Ia≤6.0 in an X-ray diffraction measurement using a Cu-Kα line. Ia represents an intensity of a peak around 2θ=28.4° attributable to Si obtained by the X-ray diffraction. Ib represents a peak intensity of a peak attributable to LiSiOobtained by the X-ray diffraction. Ic represents a peak intensity of a peak attributable to LiSiOobtained by the X-ray diffraction. Thus, the present invention provides a negative electrode active material for a non-aqueous electrolyte secondary battery, which is stable over a long period even in an aqueous slurry and enables high capacity, favorable cycle characteristics and first-time efficiency.

A negative electrode material containing a negative electrode active material particle which includes a silicon compound particle containing a silicon compound (SiO: 0.5≤x≤1.6). The silicon compound particle contains at least one or more of LiSiOand LiSiO, and the negative electrode material further contains at least one of a metal compound particle containing a metal compound and an aggregate of the metal compound particle. The negative electrode material is capable of stabilizing a slurry prepared in production of a negative electrode for a secondary battery, and improving initial charge-discharge characteristics and cycle characteristics when it is used as a negative electrode active material for a secondary battery.

Negative electrode material, method of producing the negative electrode material, and mixed negative electrode material

A negative electrode active material for a non-aqueous electrolyte secondary battery, containing negative electrode active material particles, including silicon compound particles each containing a silicon compound (SiO: 0.5≤x≤1.6) and at least one or more of LiSiOand LiSiO, the material includes a phosphate, the negative electrode active material particles each have a surface containing lithium element, and a ratio m/msatisfies 0.02≤m/m≤3, where mrepresents a molar quantity of the lithium element and contained per unit mass of the particles, and mrepresents a molar quantity of phosphorus element contained per unit mass of the particles. Thereby, a negative electrode active material is capable of stabilizing an aqueous negative electrode slurry prepared in producing a negative electrode of a secondary battery, and capable of improving initial charge-discharge characteristics when the negative electrode active material is used for a secondary battery.

Negative electrode active material, mixed negative electrode active material, aqueous negative electrode slurry composition, and method for producing negative electrode active material

Methods for producing a negative electrode active material particle which includes a silicon compound particle containing a silicon compound that contains oxygen. The methods including preparing a silicon compound particle containing a silicon compound that contains oxygen; inserting Li into the silicon compound particle; and heating, while stirring, the Li-inserted silicon compound particle in a furnace to produce a negative electrode active material particle, wherein at least part of Si constituting the silicon compound particle is present in at least one state selected from oxide of Sito Sicontaining no Li, and compound containing Li and Sito Si.

Method for producing negative electrode active material particle

A negative electrode active material containing a negative electrode active material particle which includes a silicon compound particle containing a silicon compound (SiO: 0.5&#x2264;x&#x2264;1.6). The silicon compound particle has three or more peaks in a chemical shift value ranging from &#x2212;40 ppm to &#x2212;120 ppm but has no peak in a chemical shift value within a range of &#x2212;65&#xb1;3 ppm in a spectrum obtained fromSi-MAS-NMR of the silicon compound particle. This provides a negative electrode active material capable of improving cycle characteristics when it is used as a negative electrode active material for a secondary battery.

Negative electrode active material, mixed negative electrode active material, and method of producing negative electrode active material

A negative electrode active material for a non-aqueous electrolyte secondary battery, containing a negative electrode active material particle, wherein the negative electrode active material particle includes a silicon compound particle containing a silicon compound (SiO: 0.5&#x2264;x&#x2264;1.6), the silicon compound particle contains a Li compound, at least a part of the silicon compound particle is coated with a carbon material, and an O-component fragment and a CH-component fragment are detected from the negative electrode active material particle in a measurement by TOF-SIMS, and a ratio of a peak intensity A of the O-component fragment to a peak intensity B of the CH-component fragment is 0.5&#x2264;A/B&#x2264;100. This provides a negative electrode active material for a non-aqueous electrolyte secondary battery capable of increasing battery capacity and improving the cycle characteristics and battery initial efficiency.

A negative electrode active material contains a negative electrode active material particle which includes a silicon compound particle containing a silicon compound that contains oxygen. The silicon compound particle contains a Li compound, and at least part of Si constituting the silicon compound particle is present in at least one state selected from oxide of Sito Sicontaining no Li, and compound containing Li and Sito Si. A negative electrode active material is capable of increasing battery capacity and improving cycle characteristics and initial charge-discharge characteristics when the negative electrode active material is used for a secondary battery. A mixed negative electrode active material contains the negative electrode active material. A method produces a negative electrode active material particle which enables production of the negative electrode active material particle to be contained in the negative electrode active material as described above.

Negative electrode active material, mixed negative electrode active material, and method for producing negative electrode active material particle

A negative electrode active material contains a negative electrode active material particle; the negative electrode active material particle including a silicon compound particle containing a silicon compound (SiO: 0.5&#x2264;x&#x2264;1.6), wherein the silicon compound particle contains a Li compound, and the negative electrode active material particle contains at least one kind of salt selected from salts of polyacrylic acid and salts of carboxymethyl cellulose, together with a metal salt containing at least one kind of metal selected from Mg and Al. This provides a negative electrode active material that is capable of stabilizing slurry that is produced in production of a negative electrode for a secondary battery, and improving initial charge-discharge characteristics and cycle performance when it is used as a negative electrode active material for a secondary battery.

A negative electrode active material containing a negative electrode active material particle; the negative electrode active material particle including a silicon compound particle containing a silicon compound (SiO: 0.5&#x2264;x&#x2264;1.6), wherein the silicon compound particle contains a Li compound, and the negative electrode active material particle contains an Al element and an Na element as constituent elements, with a mass ratio M/Mof the Al element and the Na element satisfying the following Formula 1. This provides a negative electrode active material that is capable of stabilizing slurry that is produced in production of a negative electrode for a secondary battery, and improving initial charge-discharge characteristics and cycle performance when it is used as a negative electrode active material for a secondary battery.0.022&#x2264;M/M&#x2264;61&#x2003;&#x2003;Formula 1

The present invention relates to a negative electrode material for nonaqueous electrolyte secondary batteries, which is composed of a silicon composite body that has a structure wherein microcrystals or fine particles of silicon are dispersed in a substance having a composition different from that of the microcrystals or fine particles, said silicon composite body having a crystallite size of the microcrystals or fine particles of 8.0 nm or less as calculated using Scherrer's equation on the basis of the half width of the diffraction peak belonging to Si(220) in an X-ray diffraction. The present invention is able to provide a negative electrode material for nonaqueous electrolyte secondary batteries, which has excellent coulombic efficiency, and a nonaqueous electrolyte secondary battery.

Negative electrode material for nonaqueous electrolyte secondary batteries, and secondary battery

The present invention provides a negative electrode material for a non-aqueous electrolyte secondary battery, comprising negative electrode active material particles containing a silicon compound expressed by SiOat least partially coated with a carbon coating where 0.5&#x2264;x&#x2264;1.6. The negative electrode active material particles have a negative zeta potential and exhibiting fragments of CHcompound in an outermost surface layer of the silicon compound when subjected to TOF-SIMS. This negative electrode material can increase the battery capacity and improve the cycle performance and battery initial efficiency. The invention also provides a negative electrode active material layer, a negative electrode, and a non-aqueous electrolyte secondary battery using this material, and a method of producing this material.

Negative electrode material for non-aqueous electrolyte secondary battery, method of producing the same, negative electrode active material layer for non-aqueous electrolyte secondary battery, negative electrode for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery

A negative electrode active material for nonaqueous electrolyte secondary batteries including: a particle of negative electrode active material, wherein the particle of negative electrode active material contains a particle of silicon compound containing a silicon compound (SiO:0.5&#x2264;x&#x2264;1.6), on at least a part of a surface of the silicon compound a carbon coating film being formed, and the negative electrode active material contains 2% by mass or less of particle of silicon dioxide and the negative electrode active material contains a silicon dioxide-carbon composite secondary particle containing a plurality of the particles of silicon dioxide and carbon. As a result, the negative electrode active material for nonaqueous electrolyte secondary batteries capable of increasing battery capacity and improving the cycle characteristics and battery initial efficiency is provided.

Negative electrode active material for nonaqueous electrolyte secondary battery, negative electrode for nonaqueous electrolyte secondary battery, nonaqueous electrolyte secondary battery, and production method of negative electrode active material for nonaqueous electrolyte secondary battery

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Takasaki, Japan

Kohta Takahashi