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

Patent metadata

Field	Value
Publication number	US-2019341602-A1
Application number	US-201816477686-A
Country	US
Kind code	A1
Filing date	Feb 26, 2018
Priority date	Mar 13, 2017
Publication date	Nov 7, 2019
Grant date	—

Abstract

A negative electrode material containing a negative electrode active material particle which includes a silicon compound particle containing a silicon compound (SiOx: 0.5≤x≤1.6). The silicon compound particle contains at least one or more of Li2SiO3 and Li4SiO4, 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.

First claim

1 .- 15 . (canceled)

16 . A negative electrode material comprising a negative electrode active material particle;
the negative electrode active material particle comprising a silicon compound particle containing a silicon compound (SiO x : 0.5≤x≤1.6), wherein the silicon compound particle contains at least one or more of Li 2 SiO 3 and Li 4 SiO 4 , and the negative electrode material further comprises at least one of a metal compound particle containing a metal compound and an aggregate of the metal compound particle.

17 . The negative electrode material according to claim 16 , wherein the metal compound particle contains at least one or more of aluminum, zirconium, and yttrium.

18 . The negative electrode material according to claim 16 , wherein
the metal compound particle has an average primary particle size of 0.1 μm or more and 4 μm or less, and the aggregate of the metal compound particle has an average secondary particle size of 0.1 μm or more and 20 μm or less.

19 . The negative electrode material according to claim 16 , wherein the metal compound has a bond between a metal element and oxygen.

20 . The negative electrode material according to claim 16 , wherein the metal compound is any one of an oxide, a phosphate, and a silicate.

21 . The negative electrode material according to claim 16 , wherein
an X-ray fluorescence spectrum obtained from X-ray fluorescence analysis of the negative electrode material has a peak indicating an aluminum Kα line around 1.49 keV and a peak indicating a silicon Kα line around 1.74 keV, and a ratio Al(Kα)/Si(Kα) of an intensity of the peak indicating the aluminum Kα line to an intensity of the peak indicating the silicon Kα line is 0.002 or more and 0.01 or less.

22 . The negative electrode material according to claim 16 , wherein an X-ray fluorescence spectrum obtained from X-ray fluorescence analysis of the negative electrode material has a peak indicating a zirconium Kα line around 15.74 keV and a peak indicating a zirconium Kβ line around 17.66 keV.

23 . The negative electrode material according to claim 16 , wherein an X-ray fluorescence spectrum obtained from X-ray fluorescence analysis of the negative electrode material has a peak indicating a yttrium Kα line around 14.93 keV but no peak indicating a yttrium Kβ line around 16.73 keV.

24 . The negative electrode material according to claim 16 , wherein
the silicon compound particle has a diffraction peak attributable to a Si(111) crystal face obtained from an X-ray diffraction using a Cu-Kα line, a half value width (2θ) of the diffraction peak is 1.2° or more, and a crystallite size corresponding to the crystal face is 7.5 nm or less.

25 . The negative electrode material according to claim 16 , wherein the silicon compound particle satisfies a relationship of A>B where A is a maximum peak intensity value in Si and Li silicate regions given as a chemical shift value of −60 to −95 ppm, and B is a peak intensity value in a SiO 2 region given as a chemical shift value of −96 to −150 ppm, the values being obtained from a 29 Si-MAS-NMR spectrum of the silicon compound particle.

26 . The negative electrode material according to claim 16 , wherein the negative electrode active material particle has a median diameter of 1.0 μm or more and 15 μm or less.

27 . The negative electrode material according to claim 16 , wherein the negative electrode active material particle has a surface layer portion containing a carbon material.

28 . The negative electrode material according to claim 27 , wherein an average thickness of the carbon material is 10 nm or more and 5000 nm or less.

29 . A mixed negative electrode material comprising:
the negative electrode material according to claim 16 ; and a carbon-based active material.

30 . A method of producing a negative electrode material containing a negative electrode active material particle including a silicon compound particle, comprising the steps of:
preparing a silicon compound particle containing a silicon compound (SiOx: 0.5≤x≤1.6); inserting Li into the silicon compound particle so as to include at least one or more of Li 2 SiO 3 and Li 4 SiO 4 to prepare a negative electrode active material particle; and mixing the negative electrode active material particle with at least one of a metal compound particle containing a metal compound and an aggregate of the metal compound particle to produce a negative electrode material.

Assignees

• Shinetsu Chemical Co

Inventors

• Matsuno Takumi
• Hirose Takakazu
• Takahashi Kohta

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• C01B33/113

  Silicon oxides; Hydrates thereof {(preparing monoxide by reduction of siliceous material C01B33/182)} · CPC title

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title