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

Patent metadata

Field	Value
Publication number	US-2018351172-A1
Application number	US-201615779155-A
Country	US
Kind code	A1
Filing date	Nov 29, 2016
Priority date	Jan 21, 2016
Publication date	Dec 6, 2018
Grant date	—

Abstract

A negative electrode active material contains particles of negative electrode active material, wherein, the particles of negative electrode active material contain particles of silicon compound which contain a silicon compound (SiOx: 0.5≤x<1.0), the particles of silicon compound contain lithium, and when the negative electrode active material is used for a negative electrode of a secondary battery having metal lithium as a counter electrode, and 1.2 V constant current discharge is carried out after 0 V constant current and constant voltage charging of the secondary battery, an obtained discharge capacity is 1,550 mAh/g or more and 2,200 mAh/g or less. According to this constitution, a negative electrode active material capable of improving discharge capacity, cycle characteristics and initial charge and discharge characteristics can be provided when it is used for a negative electrode active material of the secondary battery.

First claim

1 .- 16 . (canceled)

17 . A negative electrode active material which is a negative electrode active material containing particles of negative electrode active material, wherein,
the particles of negative electrode active material contain particles of silicon compound which contain a silicon compound (SiO x : 0.5≤x<1.0). the particles of silicon compound contain lithium, and when the negative electrode active material is used for a negative electrode of a secondary battery having metal lithium as a counter electrode, and 1.2 V constant current discharge is carried out after 0 V constant current and constant voltage charging of the secondary battery, an obtained discharge capacity is 1,550 mAh/g or more and 2,200 mAh/g or less.

18 . The negative electrode active material according to claim 17 , wherein “x” of the SiO x is in the range of 0.6≤x<0.8.

19 . The negative electrode active material according to claim 17 , wherein the particles of silicon compound contain one or more kinds selected from Li 2 SiO 3 and Li 4 SiO 4 .

20 . The negative electrode active material according to claim 17 , wherein the particles of negative electrode active material contain a carbon material at a surface layer portion.

21 . The negative electrode active material according to claim 17 , wherein the particles of negative electrode active material have a median diameter of 3.0 μm or more and 12 μm or less.

22 . A mixed negative electrode active material which comprises the negative electrode active material according to claim 17 and a carbon-based active material.

23 . A non-aqueous electrolyte secondary battery which comprises a negative electrode containing the negative electrode active material according to claim 17 .

24 . A non-aqueous electrolyte secondary battery which comprises a negative electrode containing the mixed negative electrode active material according to claim 22 .

25 . A method for producing a negative electrode active material which is a method for producing a negative electrode active material containing particles of negative electrode active material which contain particles of silicon compound, which comprises:
generating a silicon oxide gas by heating a raw material which generates a silicon oxide gas, reacting the silicon oxide gas with a reducing gas, producing particles of silicon compound containing a silicon compound (SiO x : 0.5≤x<1.0) by solidifying and depositing a material obtained by the reaction on an adsorption plate, and inserting lithium into the particles of silicon compound.

26 . A method for producing a negative electrode active material which is a method for producing a negative electrode active material containing particles of negative electrode active material which contain particles of silicon compound, which comprises:
separately preparing a container in which a raw material which generates a silicon gas is contained and a container in which a raw material which generates a silicon oxide gas is contained, generating a silicon gas by heating the raw material which generates a silicon gas, generating a silicon oxide gas by heating the raw material which generates a silicon oxide gas, mixing the silicon gas and the silicon oxide gas to obtain a mixed gas, producing particles of silicon compound containing a silicon compound (SiO x : 0.5≤x<1.0) by solidifying and depositing the mixed gas on an adsorption plate, and inserting lithium into the particles of silicon compound.

27 . The method for producing a negative electrode active material according to claim 25 , wherein a heating temperature at the time of heating the raw material which generates the silicon oxide gas is made a temperature range of 900° C. to 1,700° C.

28 . A method for producing a negative electrode active material which is a method for producing a negative electrode active material containing particles of negative electrode active material which contain particles of silicon compound, which comprises:
preparing a container in which silicon has been contained, melting the silicon contained in the container to form a silicon melt, generating a mixed gas in which a silicon gas and a silicon oxide gas are mixed by introducing a raw material which generates a silicon oxide gas into the silicon melt, producing particles of silicon compound containing a silicon compound (SiO x : 0.5≤x<1.0) by solidifying and depositing the mixed gas on an adsorption plate, and inserting lithium into the particles of silicon compound.

29 . The method for producing a negative electrode active material according to claim 25 , wherein the silicon oxide gas is generated in the presence of an inert gas or under reduced pressure.

30 . The method for producing a negative electrode active material according to claim 26 , wherein the silicon oxide gas is generated in the presence of an inert gas or under reduced pressure.

31 . The method for producing a negative electrode active material according to claim 28 , wherein the silicon oxide gas is generated in the presence of an inert gas or under reduced pressure.

32 . A method for producing a negative electrode active material which comprises producing a negative electrode active material, wherein, when the negative electrode active material is used for a negative electrode of a secondary battery having metal lithium as a counter electrode, and 1.2 V constant current discharge is carried out after 0 V constant current and constant voltage charging of the secondary battery, an obtained discharge capacity is 1,550 mAh/g or more and 2,200 mAh/g or less, by the method for producing of the negative electrode active material according to claim 25 .

33 . A method for producing a negative electrode active material which comprises producing a negative electrode active material, wherein, when the negative electrode active material is used for a negative electrode of a secondary battery having metal lithium as a counter electrode, and 1.2 V constant current discharge is carried out after 0 V constant current and constant voltage charging of the secondary battery, an obtained discharge capacity is 1,550 mAh/g or more and 2,200 mAh/g or less, by the method for producing of the negative electrode active material according to claim 26 .

34 . A method for producing a negative electrode active material which comprises producing a negative electrode active material, wherein, when the negative electrode active material is used for a negative electrode of a secondary battery having metal lithium as a counter electrode, and 1.2 V constant current discharge is carried out after 0 V constant current and constant voltage charging of the secondary battery, an obtained discharge capacity is 1,550 mAh/g or more and 2,200 mAh/g or less, by the method for producing of the negative electrode active material according to claim 28 .

35 . A method for producing a non-aqueous electrolyte secondary battery which comprises producing a negative electrode using the negative electrode active material produced by the method for producing the negative electrode active material according to claim 25 , and producing a non-aqueous electrolyte secondary battery by using the produced negative electrode.

36 . A method for producing a non-aqueous electrolyte secondary battery which comprises producing a negative electrode using the negative electrode active material produced by the method for producing the negative electrode active material according to claim 26 , and producing a non-aqueous electrolyte seco

Assignees

• Shinetsu Chemical Co

Inventors

• Hirose Takakazu
• KAMO Hiromichi
• Furuya Masahiro
• Matsuno Takumi

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/485 Primary

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M4/483 Primary

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title