Non-aqueous electrolyte secondary battery negative electrode material, and negative electrode and non-aqueous electrolyte secondary battery using the same

Patent metadata

Field	Value
Publication number	US-2020091508-A1
Application number	US-201816495474-A
Country	US
Kind code	A1
Filing date	Mar 26, 2018
Priority date	Mar 24, 2017
Publication date	Mar 19, 2020
Grant date	—

Abstract

The non-aqueous electrolyte secondary battery negative electrode material according to the invention has a core portion including carbonaceous negative electrode active material particles; and a shell portion including a polyimide and silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles. There is a feature that the value of the ratio of the volume average particle size (D50) of the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles with respect to the volume average particle size (D50) of the carbonaceous negative electrode active material particles is 0.001 to 0.1, and the content of the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles with respect to 100% by mass of the content of the carbonaceous negative electrode active material particles is 2% to 20% by mass.

First claim

1 .- 9 . (canceled)

10 . A non-aqueous electrolyte secondary battery negative electrode material comprising:
a core portion including carbonaceous negative electrode active material particles; and a shell portion including a polyimide and silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles, wherein a value of a ratio of a volume average particle size (D50) of the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles with respect to a volume average particle size (D50) of the carbonaceous negative electrode active material particles is 0.001 to 0.1, and a content of the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles with respect to 100% by mass of a content of the carbonaceous negative electrode active material particles is 2% to 20% by mass.

11 . The non-aqueous electrolyte secondary battery negative electrode material according to claim 10 , wherein the shell portion further includes a conductive aid.

12 . The non-aqueous electrolyte secondary battery negative electrode material according to claim 10 , wherein the carbonaceous negative electrode active material particles contain hard carbon.

13 . The non-aqueous electrolyte secondary battery negative electrode material according to claim 10 , wherein the silicon-based negative electrode active material particles and/or tin-based negative electrode active material particles contain simple substance of silicon or a silicon oxide.

14 . The non-aqueous electrolyte secondary battery negative electrode material according to claim 10 , wherein the polyimide includes an aromatic polyimide.

15 . The non-aqueous electrolyte secondary battery negative electrode material according to claim 10 , wherein a value of the ratio of the volume average particle size (D50) of the silicon-based and/or tin-based negative electrode active material particles with respect to the volume average particle size (D50) of the carbonaceous negative electrode active material particles is 0.001 to 0.05.

16 . A non-aqueous electrolyte secondary battery negative electrode comprising a negative electrode active material layer on a surface of a current collector,
wherein the negative electrode active material layer includes the non-aqueous electrolyte secondary battery negative electrode material according to claim 10 and conductive fibers.

17 . The non-aqueous electrolyte secondary battery negative electrode according to claim 16 , wherein the conductive fibers include carbon fibers.

18 . The non-aqueous electrolyte secondary battery negative electrode according to claim 16 , wherein a content of a binder in the negative electrode active material layer is 1% by mass or less with respect to 100% by mass of a total solid content.

19 . A non-aqueous electrolyte secondary battery comprising a power generating element including:
a non-aqueous electrolyte secondary battery negative electrode according to claim 16 ; a positive electrode comprising a positive electrode active material layer containing a positive electrode active material on a surface of a current collector; and an electrolyte layer disposed between the negative electrode and the positive electrode.

Assignees

• Nissan Motor

Inventors

• Ohsawa Yasuhiko
• Kusachi Yuki
• Satou Hajime
• Akama Hiroshi
• Horie Hideaki
• Shoji Naofumi

Classifications

• H01M4/366

  as layered products · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/387

  Tin or alloys based on tin · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01M10/052

  Li-accumulators · CPC title