Nonaqueous electrolyte secondary cell

• US 20060166098A1
• Filed: 05/06/2003
• Published: 07/27/2006
• Est. Priority Date: 05/08/2002
• Status: Active Grant

• Current Assignee: GS Yuasa International Ltd. (GS Yuasa Corporation)
• Original Assignee: GS Yuasa International Ltd. (GS Yuasa Corporation)
• Inventors: Aoki, Toshiyuki, Teshima, Minoru, Tabuchi, Toru, Nishie, Katsushi
• Granted Patent: US 8,092,940 B2
• Time in Patent Office: Days
• US Class Current: 429/232
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 2004/027 Negative electrodes
• CPC Class Codes: H01M 4/131 Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• CPC Class Codes: H01M 4/133 Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/134 Electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/364 as mixtures
• CPC Class Codes: H01M 4/366 as layered products
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/48 of inorganic oxides or hydroxides
• CPC Class Codes: H01M 4/483 for non-aqueous cells H01M4/485 takes precedence
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 4/62 Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The present invention provides a non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode having a negative active material, and a non-aqueous electrolyte; characterized in that said negative active material contains composite particle (C), which has silicon-containing particle (A) and electronic conductive additive (B), and carbon material (D), wherein the weight of said electronic conductive additive (B) falls within the range of 0.5 wt. % to 60 wt. % to the weight of said composite particle (C). The negative active material contains silicon which is capable of performing high discharge capacity, so that a non-aqueous electrolyte secondary battery having a large discharge capacity can be obtained. In addition, since the negative active material contains the electronic conductive additive (B) and the carbon material (D), the contact conductivity between the silicon-containing particle (A) or between the negative active material improves and, as a result, a non-aqueous electrolyte secondary battery having satisfactory cycle performance can be attained.

Claims

1. A non-aqueous electrolyte secondary battery comprising:

a positive electrode;

a negative electrode having a negative active material; and

a non-aqueous electrolyte;

characterized in that

said negative active material contains composite particle (C), which has silicon-containing particle (A) and electronic conductive additive (B), and carbon material (D), and

the weight of said electronic conductive additive (B) falls within the range of 0.5 wt. % to 60 wt. % to the weight of said composite particle (C).

2. The non-aqueous electrolyte secondary battery according to claim 1, characterized in that

said silicon-containing particle (A) has a content of carbon, and

said composite particle (C) is configured by coating said silicon-containing particle (A) with said electronic conductive additive (B).

3. The. non-aqueous electrolyte secondary battery according to claim 1 or claim 2, characterized in that the proportion of the weight of said composite particle (C) to the total weight of said composite particle (C) and said carbon material (D) falls within the range of 60 wt. % to 99.5 wt. %.

4. The non-aqueous electrolyte secondary battery according to claim 1 or claim 2, characterized in that said silicon-containing particle (A) has a content of silicon oxide SiOx (where O<

X≦

2).

5. The non-aqueous electrolyte secondary battery according to claim 4, characterized in that the proportion of the weight of said composite particle (C) to the total weight of said composite particle (C) and said carbon material (D) falls within the range of 1 wt. % to 30 wt. %.

6. A non-aqueous electrolyte secondary battery comprising:

a positive electrode;

a negative electrode having a negative active material; and

a non-aqueous electrolyte;

characterized in that

said negative active material has silicon-containing particle (A), and

said silicon-containing particle (A) contains silicon oxide SiOx (where O<

X≦

2) and carbon.

7. A non-aqueous electrolyte secondary battery comprising:

a positive electrode;

a negative electrode having a negative active material; and

a non-aqueous electrolyte;

characterized in that

said negative active material contains composite particle (C), which has silicon-containing particle (A) and electronic conductive additive (B),

said silicon-containing particle (A) has a content of carbon, and

when measured at a temperature rising rate of 10±

2°

C./min by thermogravimetry, said composite particle (C) exhibits two stages of weight loss in the range of 30 to 1000°

C.