Battery module, battery pack comprising same, and vehicle
A battery module prevents performance degradation due to a swelling phenomenon caused by charging and discharging and increases durability. The battery module includes a cell assembly including a plurality of battery cells stacked in a left-right direction; and a module housing configured to accommodate the cell assembly therein. The module housing includes an upper plate covering an upper portion of the cell assembly, a left plate covering a left portion of the cell assembly, a right plate covering a right portion of the cell assembly, and a lower plate covering a lower portion of the cell assembly, and at least one of the left plate and the right plate includes a support portion having a shape protruding toward the cell assembly from an inner surface facing the plurality of battery cells to pressurize at least a part of the cell assembly with a relatively small volume expansion.
1 . A battery module comprising:
a cell assembly comprising a plurality of battery cells stacked in a first direction; and
a module housing configured to accommodate the cell assembly therein,
wherein the module housing comprises an upper plate covering an upper portion of the cell assembly, a left plate, the left plate defining a left exterior of the battery module and covering a left portion of the cell assembly, a right plate, the right plate defining a right exterior of the battery module and covering a right portion of the cell assembly, and a lower plate covering a lower portion of the cell assembly,
wherein at least one of the left plate and the right plate comprises a support portion having a shape protruding toward the cell assembly from an inner surface facing the plurality of battery cells to pressurize at least a part of the cell assembly having a smaller volume expansion than a remainder of the cell assembly,
wherein the battery module further comprises an elastic pad interposed between the cell assembly and at least one of the left plate and the right plate,
wherein at least one of the upper plate and the lower plate includes bent portions at first and second ends,
wherein at least one of the left plate and the right plate includes step portions at first and second ends,
wherein the step portions are located on a side of the at least one of the left plate and the right plate facing away from the cell assembly, and
wherein the step portions are configured to seat the bent portions.
2 . The battery module of claim 1 , wherein the support portion is provided on at least one of a lower portion and an upper portion of at least one of the left plate and the right plate, and
wherein the support portion is configured to have a shape that a protruding length gradually increases as the support portion is closer to the lower plate or the upper plate.
3 . The battery module of claim 1 , further comprising an adhesive having a thermal conductivity and applied to fix one or more of an upper surface and a lower surface of the cell assembly to an inner surface of the module housing.
4 . The battery module of claim 3 , wherein the support portion protrudes toward a part of a first battery cell of the plurality of battery cells, the first battery cell being located at an outermost side in the first direction and fixed by the adhesive.
5 . The battery module of claim 1 , wherein the module housing comprises a recess portion formed as a part of the module housing facing a part of the cell assembly having a volume expansion during charging and discharging which is larger than a remainder of the cell assembly.
6 . The battery module of claim 1 , wherein the elastic pad is disposed to surround at least a part of an outer surface of the cell assembly and configured to be deformed according to a volume contraction and a volume expansion of the cell assembly, and
wherein at least a part of the elastic pad is interposed between the support portion of the module housing and the cell assembly.
7 . The battery module of claim 6 , wherein the elastic pad comprises a pressurizing portion having a part formed to protrude toward the cell assembly to pressurize the part of the cell assembly with the smaller volume expansion, on an inner surface facing the plurality of battery cells, during charging and discharging.
8 . The battery module of claim 1 , further comprising a tube filled with a fluid, the tube configured to allow the fluid to move toward the part of the cell assembly with the smaller volume expansion, during charging and discharging.
9 . The battery module of claim 1 , wherein the support portion is a concave surface of at least one of the left plate and the right plate facing the cell assembly.
10 . The battery module of claim 1 , wherein the inner surface of at least one of the left plate and right plate has a flat first portion, and a second portion extending from the first portion in a direction toward at least one of the upper plate and the lower plate and protruding further toward the cell assembly.
11 . The battery module of claim 1 , wherein at least a part of the inner surface of at least one of the left plate and the right plate has a curved shape.
12 . The battery module of claim 1 , wherein the elastic pad is in direct contact with a battery cell being located at an outermost side of the cell assembly.
13 . A battery pack comprising at least one battery module according to claim 1 .
14 . A vehicle comprising at least one battery module according to claim 1 .