Composite of metal oxide nanoparticles and carbon, method of production thereof, electrode and electrochemical element employing said composite

Patent metadata

Field	Value
Publication number	US-2016172124-A1
Application number	US-201615052726-A
Country	US
Kind code	A1
Filing date	Feb 24, 2016
Priority date	Mar 31, 2010
Publication date	Jun 16, 2016
Grant date	—

Abstract

A composite powder in which highly dispersed metal oxide nanoparticle precursors are supported on carbon is rapidly heated under nitrogen atmosphere, crystallization of metal oxide is allowed to progress, and highly dispersed metal oxide nanoparticles are supported by carbon. The metal oxide nanoparticle precursors and carbon nanoparticles supporting said precursors are prepared by a mechanochemical reaction that applies sheer stress and centrifugal force to a reactant in a rotating reactor. The rapid heating treatment in said nitrogen atmosphere is desirably heating to 400° C. to 1000° C. By further crushing the heated composite, its aggregation is eliminated and the dispersity of metal oxide nanoparticles is made more uniform. Examples of a metal oxide that can be used are manganese oxide, lithium iron phosphate, and lithium titanate. Carbons that can be used are carbon nanofiber and Ketjen Black.

First claim

What is claimed is:

1 . A method for producing a composite of metal oxide nanoparticles ,and carbon in which sheer stress and centrifugal force is applied to a solution including a starting material of metal oxide and carbon powder in a rotating reactor to allow reaction and obtain a composite powder in which highly dispersed metal oxide nanoparticle precursors are supported on carbon under nitrogen atmosphere, and the composite powder is rapidly heated under nitrogen atmosphere to allow progression of crystallization of metal oxide so that metal oxide nanoparticles having ultra thin film structure is highly dispersed and supported by the carbon.

2 . The method for producing a composite of metal oxide nanoparticles and carbon according to claim 1 , wherein the composite powder is rapidly heated under nitrogen atmosphere to 400-1000° C.

3 . The method for producing a composite of metal oxide nanoparticles and carbon according to claim 2 , wherein sheer stress and centrifugal force is applied to the solution including a reaction suppressor along with a reactant in said reactor to allow reaction.

4 . The method for producing a composite of metal oxide nanoparticles and carbon according to claim 1 , wherein the metal oxide is represented by MxOz, AxMyOz, Mx (D04) y, and AxMy (D04) z (wherein M: metal element and A: alkali metal or lanthanoids).

5 . The method for producing a composite of metal oxide nanoparticles and carbon according to claim 4 , wherein said metal oxide is any one of manganese oxide MnO, lithium iron phosphate LiFeP04, and lithium titanate Li 4 Ti 5 0 12 .

6 . A composite of metal oxide nanoparticles and carbon produced by the method according to claim 5 .

7 . An electrode obtained by mixing the composite according to said claim 1 with a binder and then shaping.

8 . An electrochemical element that employs the electrode according to claim 7 .

8 . An electrochemical element that employs the electrode according to claim 7 .

9 . The electrochemical element according to claim 8 that employs lithium iron phosphate LiFeP0 4 as the positive electrode and lithium titanate Li 4 Ti 5 0 12 as the negative electrode.

Assignees

• Nippon Chemicon

Inventors

• Naoi Katsuhiko
• Naoi Wako
• Ishimoto Shuichi
• Tamamitsu Kenji

Classifications

• H01G11/50

  specially adapted for lithium-ion capacitors, e.g. for lithium-doping or for intercalation · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/485

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