Electrochemical device

1. An electrochemical device comprising:

an element body in which a pair of a first inner electrode and a second inner electrode are laminated to sandwich a separator layer;

an exterior sheet covering the element body;

a first lead terminal which is electrically connected to the first inner electrode and is drawn to an outside of the exterior sheet; and

a second lead terminal which is electrically connected to the second inner electrode and is drawn to the outside of the exterior sheet, wherein

a proof stress of the exterior sheet is 390 to 980 N/mm 2 in JIS Z2241,

a hardness of the exterior sheet is 230 to 380 Hv in Vickers hardness (JIS Z2244),

a thickness t of the element body is 0.5 mm or less, and

a width W4 from an edge part of a pair of electrodes of the element body to a most inner end of a seal part is 1 mm or larger.

2. The electrochemical device as set forth in claim 1 , wherein a peripheral edge of the exterior sheet is sealed by the seal part so that the element body is immersed in an electrolyte solution and

the first lead terminal and the second lead terminal are drawn to an outside of the seal part at mutually opposite positions along a longitudinal direction of the first inner electrode and the second inner electrode.

3. The electrochemical device as set forth in claim 2 , wherein sealing tapes sandwiching the first lead terminal and the second lead terminal respectively are inserted between the peripheral edges of the exterior sheet and thermally sealed, in order that the seal part is partially formed.

4. The electrochemical device as set forth in claim 3 , wherein a width of the seal part corresponding to a length of the sealing tape is 1 mm or more.

5. The electrochemical device as set forth in claim 2 , further comprising a support sheet which prevents bending of the first lead terminal and the second lead terminal drawn from the seal part.

6. The electrochemical device as set forth in claim 5 , wherein the support sheet is formed by outwardly extending a part of a peripheral edge of the exterior sheet located at the seal part.

7. The electrochemical device as set forth in claim 5 , wherein a protruding length of the support sheet is longer than that of the first lead terminal and the second lead terminal.

8. An electrochemical device comprising:

an element body in which a pair of a first inner electrode and a second inner electrode are laminated to sandwich a separator layer;

an exterior sheet covering the element body;

a first lead terminal which is electrically connected to the first inner electrode and is drawn to an outside of the exterior sheet; and

a second lead terminal which is electrically connected to the second inner electrode and is drawn to the outside of the exterior sheet, wherein

a proof stress of the exterior sheet is 390 to 980 N/mm2 in JIS Z2241,

a hardness of the exterior sheet is 230 to 380 Hv in Vickers hardness (JIS Z2244),

a material of a metal sheet of the exterior sheet is SUS304 (BA) or SUS304 (1/2H), and

a width W4 from an edge part of a pair of electrodes of the element body to a most inner end of a seal part is 1 mm or larger.

9. The electrochemical device as set forth in claim 8 , wherein a thickness of the element body is 1 mm or less.

10. The electrochemical device as set forth in claim 8 , wherein a peripheral edge of the exterior sheet is sealed by a seal part so that the element body is immersed in an electrolyte solution and

the first lead terminal and the second lead terminal are drawn to an outside of the seal part at mutually opposite positions along a longitudinal direction of the first inner electrode and the second inner electrode.

11. The electrochemical device as set forth in claim 10 , wherein a thickness of the element body is 1 mm or less.

12. The electrochemical device as set forth in claim 11 , wherein sealing tapes sandwiching the first lead terminal and the second lead terminal respectively are inserted between the peripheral edges of the exterior sheet and thermally sealed, in order that the seal part is partially formed.

13. The electrochemical device as set forth in claim 12 , wherein a width of the seal part corresponding to a length of the sealing tape is 1 mm or more.

14. The electrochemical device as set forth in claim 11 , further comprising a support sheet which prevents bending of the first lead terminal and the second lead terminal drawn from the seal part.

15. The electrochemical device as set forth in claim 14 , wherein the support sheet is formed by outwardly extending a part of a peripheral edge of the exterior sheet located at the seal part.

16. The electrochemical device as set forth in claim 14 , wherein a protruding length of the support sheet is longer than that of the first lead terminal and the second lead terminal.

17. The electrochemical device as set forth in claim 10 , wherein sealing tapes sandwiching the first lead terminal and the second lead terminal respectively are inserted between the peripheral edges of the exterior sheet and thermally sealed, in order that the seal part is partially formed.

18. The electrochemical device as set forth in claim 17 , wherein a width of the seal part corresponding to a length of the sealing tape is 1 mm or more.

19. The electrochemical device as set forth in claim 10 , further comprising a support sheet which prevents bending of the first lead terminal and the second lead terminal drawn from the seal part.

20. The electrochemical device as set forth in claim 19 , wherein the support sheet is formed by outwardly extending a part of a peripheral edge of the exterior sheet located at the seal part.

21. The electrochemical device as set forth in claim 19 , wherein a protruding length of the support sheet is longer than that of the first lead terminal and the second lead terminal.