Pouch case, and secondary battery and secondary battery pack using the same
Provided is a pouch case including first and second accommodation portions formed to accommodate the electrode assembly, a sealing portion formed along an outer part of the pouch case to surround the first and second accommodation portions, and a connecting portion formed with the same depth as that of the first and second accommodation portion and configured to connect the first and second accommodation portions at a predetermined interval, wherein a protrusion protrudes in a direction toward the sealing portion at opposite ends of the connecting portion. Accordingly, in the pouch case, and a secondary battery and a secondary battery pack using the same, a perfect cooling structure is acquired by uniformly forming one side surface of the secondary battery, and thus, an effect of holding one side surface of the secondary battery to be close to a cooling plate to maximize cooling efficiency is achieved.
1. A secondary battery pack comprising:
a plurality of secondary batteries; and
a cooling plate including a first side surface, a second side surface facing the first side surface, and an upper surface, which surface contacts side surfaces of the plurality of secondary batteries;
wherein a sealing portion of each of the secondary batteries includes extension portions protruding by a predetermined length in a perpendicular direction to the side surface of each of the secondary batteries at respective portions adjacent to opposite end portions in a longitudinal direction of the side surface of each of the secondary batteries,
wherein a step difference is formed with a height equal to or larger than the predetermined length of the extension portion of each of the secondary batteries on each of the first and second side surfaces of the cooling plate,
wherein the upper surface of the cooling plate is formed with a flat shape as a whole, and
wherein the side surface of each of the secondary batteries is formed with a flat shape as a whole.
2. The secondary battery pack of claim 1 , wherein a width between the first and second side surfaces of the cooling plate is larger than a length of a connecting portion of each of the secondary batteries.
3. The secondary battery pack of claim 1 , wherein the extension portion of each of the secondary batteries is formed to be put on the step difference formed on the cooling plate.
4. The secondary battery pack of claim 1 , wherein dimples that are recessed toward an internal part of each of the secondary batteries are formed at opposite ends of the side surface of each of the secondary batteries.