Nonaqueous electrolyte secondary battery

• US 6,926,992 B2
• Filed: 07/01/2002
• Issued: 08/09/2005
• Est. Priority Date: 06/29/2001
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Satoh, Yuji, Kanda, Motoya, Isozaki, Yoshiyuki
• Primary Examiner(s): DOVE, TRACY MAE
• Application Number:
  US10/184,851
• Publication Number:
  US 20030031919A1
• Time in Patent Office: 1,135 Days
• Field of Search: 429/53, 429/54, 429/56, 429/57, 429/59, 429/82, 429/175
• US Class Current: 429/59
• 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 50/107 having curved cross-section, e.g. round or elliptic H01M50/103, H01M50/109, H01M50/11 take precedence
• CPC Class Codes: H01M 50/184 characterised by their shape or structure
• CPC Class Codes: H01M 50/186 characterised by the disposition of the sealing members
• CPC Class Codes: H01M 50/3425 in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member
• CPC Class Codes: H01M 50/578 in response to pressure
• CPC Class Codes: H01M 6/10 with wound or folded electrodes
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Disclosed is a nonaqueous electrolyte secondary battery comprises a sealing unit including a conductive support plate, wherein the conductive support plate contains at least one kind of a conductive material selected from the group consisting of a metal, an alloy and a composite metallic material, each of the metal, the alloy and the composite metallic material has a modulus of elasticity (Young'"'"'s modulus) at 25° C. that falls within a range from 1×10¹¹ Pa to 3.27×10¹¹ Pa, and the conductive support plate has an area resistance value RS at 20° C. falling within a range from 0.032 (μΩ·cm²) to 1.24 (μΩ·cm²).

Claims

1. A nonaqueous electrolyte secondary battery comprising:

a case;

an electrode group provided in the case and including a positive electrode, a negative electrodes, and a nonaqueous electrolyte; and

a sealing unit arranged in an open portion of the case, the sealing unit including a conductive safety vent comprising a rupture portion that is ruptured by an increase in an internal pressure of the case, a positive electrode terminal electrically connected to the positive electrode, and a conductive support plate arranged between the conductive safety vent and the positive electrode terminal, wherein;

the conductive support plate is formed of a composite matellic material, the composite metallic material being a clad material comprising a Cu-containing layer and Ni-containing layers formed on both surfaces of the Cu-containing layer;

a ratio of a total thickness of the Ni-containing layers to a thickness of the Cu-containing layer is within a range between 0.1;

1 and 1;

1; and

the conductive support plate has an area resistance value RS at 20°

C. falling within a range from 0.032 μ

Ω

·

cm² to 1.24 μ

Ω

·

cm².

2. The nonaqueous electrolyte secondary battery according to claim 1, wherein the area resistance value RS at 20°

C. of the conductive support plate falls within a range from 0.05 μ

Ω

·

cm² to 0.35 μ

Ω

·

cm².

3. The nonaqueous electrolyte secondary battery according to claim 1, wherein a thickness of the conductive support plate falls within a range from 0.2 mm to 0.5 mm.

4. The nonaqueous electrolyte secondary battery according to claim 1, wherein the conductive safety vent includes a recessed portion recessed downward and an annular peripheral portion arranged around an upper edge of the recessed portion, and the rupture portion is a groove formed on a surface of the recessed portion.

5. The nonaqueous electrolyte secondary battery according to claim 4, wherein the conductive safety vent is formed of aluminum or an aluminum alloy.

6. The nonaqueous electrolyte secondary battery according to claim 1, wherein the ratio of the total thickness of the Ni-containing layers to the thickness of the Cu-containing layers is within a range between 0.25:

1 and 0.5;

1.

7. The nonaqueous electrolyte secondary battery according to claim 1, wherein the area resistance value RS at 20°

C. of the conductive support plate falls within a range from 0.05 μ

Ω

·

cm² to 0.21 μ

Ω

·

cm².

8. The nonaqueous electrolyte secondary battery according to claim 1, wherein the thickness of the conductive support plate falls within a range from 0.25 mm to 0.35 mm.

9. The nonaqueous electrolyte secondary battery according to claim 1, wherein a percentage of Ni and Cu contained in the conductive support plate is 80% by weight or more.

10. The nonaqueous electrolyte secondary battery according to claim 1, wherein a percentage of Ni and Cu contained in the conductive support plate falls within a range from 90 to 100% by weight.

11. The nonaqueous electrolyte secondary battery according to claim 1, wherein a percentage of Ni and Cu contained in the conductive support plate falls within a range from 95 to 100% by weight.

12. A nonaqueous electrolyte secondary battery comprising:

a case;

an electrode group provided in the case and including a positive electrode, a negative electrode, and a nonaqueous electrolyte; and

a sealing unit arranged in an open portion of the case, the sealing unit including a conductive safety vent comprising a rupture portion that is ruptured by an increase in an internal pressure of the case, a positive electrode terminal electrically connected to the positive electrode, and a conductive support plate arranged between the conductive safety vent and the positive electrode terminal;

wherein;

the conductive support plate comprises a Cu-containing plate as a supporting body, a first Ni-containing layer plated on one main surface of the Cu-containing plate and a second Ni-containing layer plated on another main surface of the Cu-containing plate;

a sum of a thickness of the first Ni-containing layer and a thickness of the second Ni-containing layer falls within a range from 2 μ

m to 10 μ

m; and

the conductive support plate has an area resistance value RS 20°

C. falling within a range from 0.032 μ

Ω

·

cm² to 1.24 μ

Ω

·

cm².

13. The nonaqueous electrolyte secondary battery according to claim 12, wherein the area resistance value RS of the conductive support plate falls within a range from 0.05 μ

Ω

·

cm² to 0.35 μ

Ω

·

cm².

14. The nonaqueous electrolyte secondary battery according to claim 12, wherein a thickness of the conductive support plate falls within a range from 0.2 mm to 0.5 mm.

15. The nonaqueous electrolyte secondary battery according to claim 12, wherein the sum of the thickness of the first Ni-containing layer and the thickness of the second Ni-containing layer falls within a range from 4 μ

m to 6 μ

m.

16. The nonaqueous electrolyte secondary battery according to claim 12, wherein the area resistance value RS at 20°

C. of the conductive support plate falls within a range from 0.05 μ

Ω

·

cm² to 0.21 μ

Ω

·

cm².

17. The nonaqueous electrolyte secondary battery according to claim 12, wherein the thickness of the conductive support plate fails within a range from 0.25 mm to 0.35 mm.

18. The nonaqueous electrolyte secondary battery according to claim 12, wherein a percentage of Ni and Cu contained in the conductive support plate is 80% by weight or more.

19. The nonaqueous electrolyte secondary battery according to claim 12, wherein a percentage of Ni and Cu contained in the conductive support plate falls within a range from 90 to 100% by weight.

20. The nonaqueous electrolyte secondary battery according to claim 12, wherein a percentage of Ni and Cu contained in the conductive support plate falls within a range from 95 to 100% by weight.