Secondary battery and battery module having thereof

1. A secondary battery, comprising:

a cell body member accommodating an electrode assembly therein, including three sealing sides and provided adjacently to a cooling plate member,

wherein the cell body member, in contact with a heat conductive member on a lower surface thereof, comprises a surface area-increasing groove formed to be concave in the lower surface thereof and the lower surface is a region in which a sealing portion is not formed,

wherein the heat conductive member provided in at least a portion between the cell body member and the cooling plate member to form a heat path for transferring heat from the cell body member to the cooling plate member,

wherein the surface area-increasing groove includes a curved-region in a cross section in a thickness direction of the cell body member, and

wherein the curved-region is in contact with the heat conductive member.

2. The secondary battery of claim 1 , wherein the cell body member is formed to have the surface area-increasing groove formed to be asymmetrical.

3. The secondary battery of claim 2 , wherein the surface area-increasing groove is asymmetrical in a thickness direction of the cell body member.

4. The secondary battery of claim 3 , wherein the surface area-increasing groove has one side formed to have a first radius of curvature in the thickness direction of the cell body member and the other side, connected thereto, formed to have a second radius of curvature, wherein the first and second radii of curvature are different from each other.

5. The secondary battery of claim 1 , wherein the cell body member is formed to have the surface area-increasing groove formed in a central portion in the thickness direction to be elongated in a length direction.

6. The secondary battery of claim 1 , wherein the cell body member is formed with the surface area-increasing groove in the central portion of a thickness direction and a rounded portion at both ends in the thickness direction.

7. The secondary battery of claim 6 , wherein the cell body member has the rounded portion having a radius of curvature smaller than a radius of curvature of the surface area-increasing groove.

8. A battery module, comprising:

a plurality of stacked secondary batteries, wherein each secondary battery includes a cell body member accommodating an electrode assembly therein, the cell body member including three sides;

a heat conductive member provided in at least a portion between the cell body member and a cooling plate member; and

a housing member comprising the cooling plate member for exchanging heat with the cell body member mediated by the heat conductive member and accommodating the plurality of stacked secondary batteries therein,

wherein the cell body member comprises a surface area-increasing groove formed to be concave on a lower surface thereof in contact with the heat conductive member, and the lower surface is a region in which a sealing portion is not formed,

wherein the surface area-increasing groove includes a curved-region in a cross section in a thickness direction of the cell body member, and

wherein the curved-region is in contact with the heat conductive member.

9. The battery module of claim 8 , wherein the surface area-increasing groove is asymmetrical in a thickness direction of the cell body member.

10. The battery module of claim 9 , wherein the surface area-increasing groove has one side formed to have a first radius of curvature in the thickness direction of the cell body member and the other side, connected thereto, formed to have a second radius of curvature, wherein the first and second radii of curvature are different from each other.

11. The battery module of claim 10 , wherein, when the cell body member is seated and coupled onto the heat conductive member applied to the cooling plate member, the surface area-increasing groove has the first radius of curvature of the one side initially contacting the heat conductive member applied to the cooling plate member greater than the second radius of curvature.

12. The battery module of claim 8 , wherein the cooling plate member has a surface-increasing tap formed to protrude from a portion in which the cell body member is seated and having at least a portion inserted in the surface area-increasing groove.

13. The battery module of claim 12 , wherein the surface-increasing tap is formed to protrude to correspond to a shape of the surface area-increasing groove.

14. The battery module of claim 12 , wherein the surface-increasing tap is formed to have a width smaller than a width of the surface area-increasing groove in the thickness direction of the cell body member.

15. The battery module of claim 8 , wherein the housing member further includes a side wall forming a side portion of the housing member.

16. The battery module of claim 8 , wherein the housing member further includes a cover member provided on an upper end of the side wall to protect an upper end of the secondary batteries.

17. The battery module of claim 8 , wherein the housing member further includes a bus bar for electrically connecting the secondary batteries.

18. The battery module of claim 8 , wherein the cell body member is formed with the surface area-increasing groove in the central portion of a thickness direction and a rounded portion at both ends in the thickness direction, wherein a radius of curvature of the rounded portion is smaller than a radius of curvature of the surface area-increasing groove.

19. The battery module of claim 8 , wherein the cell body member comprises the surface area-increasing groove formed in a central portion in a thickness direction to accommodate the heat conductive member and both ends in the thickness direction to be in contact with the cooling plate member.