| 摘要 |
<p>PURPOSE: A middle or large-sized battery pack case is provided to minimize the temperature deviation between unit cells, to remove the heat accumulated between unit cells, and to improve performance and life span of a battery. CONSTITUTION: A middle or large-sized battery pack case(370) includes a battery module where a plurality of rechargeable battery cells or unit modules ('unit cell') are stacked. A refrigerant inlet(310) and a refrigerant outlet(320) are positioned at the upper part and lower part of the pack case in a counter direction so that refrigerant for cooling unit cells flows into the opposite side from one side of the battery module in the direction perpendicular to a cell stacking direction. A flow space ('refrigerant inlet portion') from the refrigerant inlet to the battery module and a flow space ('refrigerant outlet portion') from the battery module to the refrigerant outlet are respectively formed in the pack case.; An inner surface of the upper end of the refrigerant inlet portion, which faces the upper end portion of a unit cell stack, has a structure with the surface inclined at a positive (+) angle (A) relative to the upper end surface of the unit cell stack, wherein the surface is inclined to the refrigerant inlet from the opposite end portion of the refrigerant inlet. The refrigerant inlet is inclined at an angle (B) larger than the angle (A) of the inclined surface corresponding to a structure of the inner surface of a device on which the medium and large-sized battery pack case including the battery module is mounted. When the angle (B) of slope of the refrigerant inlet is 20-80 degrees, the angle (A) of slope of the inclined surface is 3-8 degrees.</p> |
