Active material, method of manufacturing active material, electrode, and secondary battery

Patent metadata

Field	Value
Publication number	US-2015318542-A1
Application number	US-201314432187-A
Country	US
Kind code	A1
Filing date	Oct 4, 2013
Priority date	Oct 5, 2012
Publication date	Nov 5, 2015
Grant date	—

Abstract

A secondary battery includes a cathode, an anode including an active material, and non-aqueous electrolytic solution. The active material includes a center portion and a covering portion provided on part or all of the center portion. The center portion includes silicon, tin, or both as constituent elements. The covering portion includes a plurality of fibrous carbon materials. Part or all of the fibrous carbon materials extend in a direction along a surface of the center portion and are closely attached to the center portion.

First claim

1 . A secondary battery, comprising:
a cathode; an anode including an active material; and non-aqueous electrolytic solution, the active material including a center portion and a covering portion provided on part or all of the center portion, the center portion including silicon (Si), tin (Sn), or both as constituent elements, the covering portion including a plurality of fibrous carbon materials, and part or all of the fibrous carbon materials extending in a direction along a surface of the center portion and being closely attached to the center portion, and being tangled with one another.

2 . The secondary battery according to claim 1 , wherein the covering portion includes a mesh structure that is formed of part or all of the fibrous carbon materials.

3 . The secondary battery according to claim 1 , wherein
the anode includes a plurality of the active materials, and part of the fibrous carbon materials are cross-linked to one another between the active materials.

4 . The secondary battery according to claim 1 , wherein the fibrous carbon materials include one or more carbon nanotubes, one or more carbon nanofibers, or both.

5 . The secondary battery according to claim 1 , wherein 85 percent or higher of the fibrous carbon materials have a fiber length of 4 micrometers or smaller.

6 . The secondary battery according to claim 1 , wherein the fibrous carbon materials have an average fiber diameter of 102 nanometers or smaller.

7 . The secondary battery according to claim 1 , wherein a ratio of area of G-band peak to area of D-band peak (the area of the G-bank peak/the area of the D-band peak) is 1 or higher in Raman spectrum of the fibrous carbon materials that is measured by Raman spectroscopy.

8 . The secondary battery according to claim 1 , wherein
the anode includes a plurality of the active materials, and the center portion has a median system (D50) of 7.8 micrometers or surface thereof.

9 . The secondary battery according to claim 1 , wherein part of all of the fibrous carbon materials each have a carboxyl group (—COOH) on a surface thereof.

10 . The secondary battery according to claim 1 , wherein a peak derived from a 1s orbit (O1s) of oxygen (O) is detected as a result of element analysis of the fibrous carbon materials by X-ray photoelectron spectroscopy (XPS).

11 . The secondary battery according to claim 1 , wherein the center portion includes one or more of a simpler substance of silicon, alloy of silicon, a compound of silicon, a simple substance of tin, alloy of tin, and a compound of tin.

12 . The secondary battery according to claim 1 , wherein
the active material includes an intermediate portion provided on part of all of the center portion, the intermediate portion including carbon (C) as a constituent element, and the covering portion is provided on the center portion with the intermediate portion in between.

13 . The secondary battery according to claim 1 , wherein the anode includes another active material including carbon as a constituent element.

14 . The secondary battery according to claim 1 , wherein the secondary battery is a lithium ion secondary battery.

15 . An electrode, comprising
an active material including a center portion and a covering portion provided on apart or all of the center portion, the center portion including silicon (Si), tin (Sn), or both as constituent elements, the covering portion including a plurality of fibrous carbon materials, and part of all of the fibrous carbon materials extending in a direction along a surface of the center portion, being closely attached to the center portion, and being tangled with one another.

16 . An active material, comprising
a center portion; and a covering portion provided on part or all of the center portion, the center portion including silicon (Si), tin (Sn), or both as constituent elements, the covering portion including a plurality of fibrous carbon materials, and part of all of the fibrous carbon materials extending in a direction along a surface of the center portion, being closely attached to the center portions, and being tangled with one another.

17 . A method of manufacturing an active material, the method comprising bringing sol solution that includes a plurality of fibrous carbon materials into contact with part or all of a center portion, then heating the sol solution, and thereby forming a covering portion including the fibrous carbon materials, the center portion including silicon (Si), tin (Sn), or both as constituent elements.

18 . (canceled)

Assignees

• Sony Corp

Inventors

• Morozumi Takeshi
• Kitada keitaro
• Nagata Yoshihide
• Munaoka Takatoshi
• Matsubara Kenji
• Ohtaniuchi Yuko
• Kanazawa Aiko
• Nagaoka Nobuyuki
• Kikkawa Masahiro

Classifications

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M2220/10

  Batteries in stationary systems, e.g. emergency power source in plant · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/387

  Tin or alloys based on tin · CPC title