ELECTRODE STRUCTURE FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, METHOD FOR PRODUCING THE SAME, AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

• US 20100285353A1
• Filed: 06/24/2009
• Published: 11/11/2010
• Est. Priority Date: 06/25/2008
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Kasamatsu, Takeshi, Kato, Seiichi, Imashiku, Shoichi, Katayama, Hitoshi, Sumihara, Masanori, Nonoshita, Takashi
• Granted Patent: US 8,530,084 B2
• Time in Patent Office: Days
• US Class Current: 429/185
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/058 Construction or manufacture
• CPC Class Codes: H01M 4/70 characterised by shape or form
• CPC Class Codes: H01M 4/742 perforated material
• CPC Class Codes: H01M 50/533 characterised by the shape of the leads or tabs
• CPC Class Codes: H01M 50/534 characterised by the material of the leads or tabs
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

An electrode 13 has an active material layer 12 formed on each of two whole main surfaces of a current collector 11. A part of an electrode lead 14 overlaps the electrode 13. One end face of the electrode 13 in the width direction of the electrode 13 is flush with one end face of the electrode lead 14. Joints 15 are formed at the one end of the electrode 13 in the width direction. The joints 15 join the electrode 13 and the electrode lead 14 so as to provide electrical continuity between the exposed part of the current collector 11 at the one end face of the electrode 13 in the width direction and the electrode lead 14. The joints 15 are formed, for example, by plasma welding.

Claims

1. An electrode structure for a non-aqueous electrolyte secondary battery, comprising:

an electrode including a current collector with two main surfaces and an active material layer formed on each of the main surfaces of the current collector, the current collector comprising a long strip-like metal foil and having an exposed part at at least one of an end of the electrode, a through-hole penetrating through the electrode, and a recess formed by removing the active material layer from one of the main surfaces of the electrode;

an electrode lead; and

a joint for joining the electrode and the electrode lead so as to provide electrical continuity between the exposed part of the current collector and the electrode lead.

2. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 1, wherein the joint is formed at one end of the electrode in the width direction of the electrode.

3. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 2,

wherein the electrode lead has a part overlapping the electrode and one end face which is disposed so as to be flush with an end face of the electrode at the one end in the width direction, and

the joint is formed so as to extend over the end face of the electrode at the one end in the width direction and the one end face of the electrode lead.

4. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 3, further comprising an additional joint formed at the other end of the electrode in the width direction.

5. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 4,

wherein the electrode lead has a step that is formed so as to be flush with an end face of the electrode at the other end in the width direction, and

the joint formed at the other end joins the current collector exposed at the other end of the electrode in the width direction and the step of the electrode lead.

6. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 3,

wherein the electrode lead is affixed to the other end of the electrode in the width direction with adhesive tape.

7. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 2,

wherein the joint comprises a first contact part in contact with one end face of the electrode lead, a second contact part in contact with an end face of the electrode at the one end, and a bent part between the first contact part and the second contact part, and

the one end face of the electrode lead faces the end face of the electrode at the one end.

8. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 1, wherein the joint is formed at one end of the electrode in the longitudinal direction of the electrode.

9. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 8,

wherein the electrode lead has a part overlapping the electrode and one end face which is disposed so as to be flush with an end face of the electrode at the one end in the longitudinal direction, and

the joint is formed so as to extend over the end face of the electrode at the one end in the longitudinal direction and the one end face of the electrode lead.

10. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 9,

wherein the other end of the electrode lead is affixed to the electrode with adhesive tape.

11. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 1,

wherein the electrode lead has a part which is cut and raised, and the joint comprises the cut-raised part inserted and resolidified in the through-hole.

12. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 11,

wherein the cut-raised part of the electrode lead has a sharp tip.

13. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 11, wherein the cut-raised part of the electrode lead has a quadrangular shape.

14. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 11, wherein the cut-raised part of the electrode lead has a rounded tip.

15. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 1,

wherein the electrode has the through-hole or recess shaped like a slit at a position overlapping or adjacent to an end of the electrode lead, and

the joint comprises the end of the electrode lead resolidified so as to join the current collector exposed in the slit-like through-hole or recess and the electrode lead.

16. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 15,

wherein the slit-like through-hole or recess is parallel to the longitudinal direction of the electrode.

17. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 15,

wherein the slit-like through-hole or recess is perpendicular to the longitudinal direction of the electrode.

18. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 15,

wherein the slit-like through-hole or recess is slanted relative to the longitudinal direction of the electrode.

19. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 1, wherein the electrode lead has a crimped part penetrating through the thickness of the electrode.

20. The electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 1, wherein the electrode lead and the electrode overlap each other and are bonded together at the overlapping part with adhesive.

26. A non-aqueous electrolyte secondary battery comprising:

an electrode assembly comprising a positive electrode and a negative electrode which are wound or layered with a separator interposed therebetween, each of the positive and negative electrodes being shaped like a long strip;

an electrode lead joined to the positive electrode and an electrode lead joined to the negative electrode;

a non-aqueous electrolyte;

a battery case housing the electrode assembly and the non-aqueous electrolyte; and

a seal member sealing an opening of the battery case,

wherein at least one of an electrode structure comprising the electrode lead joined to the positive electrode and an electrode structure comprising the electrode lead joined to the negative electrode is the electrode structure of claim 1 for a non-aqueous electrolyte secondary battery.

21. A method for producing an electrode structure for a non-aqueous electrolyte secondary battery, comprising the steps of:

(a) providing an electrode having an active material layer on each of two main surfaces of a current collector comprising a long strip-like metal foil, the current collector being exposed at at least one of an end of the electrode, a through-hole penetrating through the electrode, and a recess formed by removing the active material layer from one of the main surfaces of the electrode; and

(b) forming a joint that joins the exposed current collector and an electrode lead so as to provide electrical continuity therebetween.

22. The method for producing an electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 21,

wherein the step b comprises the steps of:

overlapping the electrode lead and the electrode so that one end face of the electrode lead is flush with one end face of the electrode in the width direction of the electrode; and

forming the joint so as to extend over the one end face of the electrode lead and the one end face of the electrode in the width direction.

23. The method for producing an electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 22,

wherein the step b further includes the step of turning around the joint so that the one end face of the electrode lead faces the one end face of the electrode in the width direction.

24. The method for producing an electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 21,

wherein the step b comprises the steps of cutting and raising a part of the electrode lead, inserting the cut-raised part of the electrode lead in the through-hole, melting the cut-raised part, and resolidifying the molten cut-raised part to form the joint.

25. The method for producing an electrode structure for a non-aqueous electrolyte secondary battery in accordance with claim 21,

wherein the step b comprises the steps of:

forming the through-hole or recess shaped like a slit at a position overlapping or adjacent to an end of the electrode lead; and

melting the end of the electrode lead so as to cause a molten portion to flow into the slit-like through-hole or recess and resolidifying the molten portion to form the joint.