Vehicle battery pack assembly

1 . A vehicle battery pack assembly comprising:

a battery module including a plurality of battery cells stacked and provided in a transverse direction, and an endplate provided at an outermost side of the battery module in a width direction of the battery module and formed with a mounting portion protruding outward therefrom; and

a battery casing provided with a casing member extending along a longitudinal direction of the battery module, the casing member, of which a surface facing toward the battery module is in surface-contact with the endplate to support a surface pressure of the battery module,

wherein the casing member is internally divided into an upper space and a lower space by an intermediate wall,

wherein the intermediate wall of the casing member is formed with a fastening groove at a position corresponding to the mounting portion,

wherein an upper side of the upper space at the fastening groove is open, and

wherein the mounting portion is inserted into the fastening groove in a vertical direction and fastened to the casing member.

2 . The vehicle battery pack assembly of claim 1 , further including a compression pad mounted between the battery cells to compensate for a space caused by contract and expansion of the battery cells.

3 . The vehicle battery pack assembly of claim 1 , wherein the casing member includes:

side members provided at opposite sides of the battery casing in the longitudinal direction;

a middle member provided between the side members in the longitudinal direction; and

crossing members provided between the side members and the middle member in the transverse direction,

wherein the battery module is provided in a lateral direction with respect to the middle member between the side members.

4 . The vehicle battery pack assembly of claim 3 , wherein the side members, the middle member and the crossing members support the battery module in the lateral direction.

5 . The vehicle battery pack assembly of claim 1 , wherein the casing member has a cross-section of which includes a plurality of hollow portions.

6 . The vehicle battery pack assembly of claim 5 , wherein the mounting portion supports the endplate and the intermediate wall when inserted in the fastening groove and fastened to the casing member.

7 . The vehicle battery pack assembly of claim 1 ,

wherein the mounting portion includes a plurality of mounting portions, and

wherein the fastening groove includes a plurality of fastening grooves formed in the casing member and spaced apart at predetermined intervals, and the mounting portions are respectively inserted in the fastening grooves and fastened to the casing member.

8 . The vehicle battery pack assembly of claim 1 , wherein the mounting portion is inserted in the fastening groove and fastened to the casing member by bolting the mounting portion and the casing member.

9 . The vehicle battery pack assembly of claim 1 , wherein the mounting portion is formed to overlap with a middle point of the endplate with respect to a height direction of the battery module.

10 . The vehicle battery pack assembly of claim 1 ,

wherein a portion in the casing member, to which the mounting portion inserted in the fastening groove is fastened, is formed at a same height as the mounting portion.

11 . The vehicle battery pack assembly of claim 10 ,

wherein a portion in the casing member, in which the mounting portion is not inserted and fastened to the fastening groove, is formed at a same or lower height than the battery module.

12 . The vehicle battery pack assembly of claim 5 ,

wherein a lateral surface of the lower space is in surface-contact with the endplate and supports the surface pressure of the battery module in a portion of the casing member to which the mounting portion inserted in the fastening groove is fastened.

13 . The vehicle battery pack assembly of claim 5 ,

wherein lateral surfaces of the upper space and the lower space are in surface-contact with the end plate and support the surface pressure of the battery module in a portion of the casing member in which the mounting portion is not inserted in and not fastened to the fastening groove.

14 . The vehicle battery pack assembly of claim 3 ,

wherein the side members of the casing member are formed with a flange to be coupled to a vehicle body.