Battery module of improved stability

1. A battery module having a plurality of plate-shaped battery cells, each of which has electrode terminals respectively formed at an upper end and a lower end thereof, the battery module comprising:

two battery cells;

a buffering member disposed at an interface between the battery cells to restrain movement of the battery cells and to buffer volume change of the battery cells during charge and discharge of the battery cells; and

a pair of module housings coupled to entirely cover an outside of a stack of the battery cells excluding the electrode terminals of the battery cells, each of the module housings being formed of a sheet, wherein

the buffering member is disposed inside the coupled pair of module housings,

each of the module housings has an internal structure corresponding to a shape of the outside of the battery cell stack,

sectional coupling portions of the module housings are configured to have male and female fastening structures, by which the module housings are engaged with each other by elastic coupling when the module housings are pressed in a state in which the module housings are in contact with each other such that the module housings face each other,

each of the module housings is provided at sides adjacent to an upper end and a lower end thereof with depressed steps of a predetermined size to fix the battery cells,

each of the depressed steps has a shape and size corresponding to a sealed portion of each of the battery cells,

the battery module consisting of a sequentially stacked arrangement of a first module housing of the pair of module housings, one of the two battery cells, the buffering member, another of the two battery cells, and a second module housing of the pair of module housings, and

each of the module housings is provided at a top and bottom of an outside thereof with a first bar having a first shape extending in a width direction of the module housing and a second bar having a second shape extending in the width direction of the module housing, the first shape and second shape being configured to cooperate with each other such that when adjacent battery modules are fit together they fit with only a single orientation.

2. The battery module according to claim 1 , wherein each of the plate-shaped battery cells is configured to have a structure in which an electrode assembly is mounted in a battery case formed of a laminate sheet comprising a metal layer and a resin layer, and outer edges of the battery case is sealed.

3. The battery module according to claim 1 , wherein the buffering member is formed of a polymer resin having a porous structure.

4. The battery module according to claim 1 , wherein the buffering member is configured to have a porous structure comprising open pores or closed pores.

5. The battery module according to claim 1 , wherein each of the module housings is formed of a metal sheet.

6. The battery module according to claim 1 , wherein each of the module housings is provided at the outside thereof with a plurality of linear beads spaced apart from each other in a width direction (lateral direction) to provide a coolant flow space.

7. The battery module, according to claim 6 , wherein each of the beads has opposite ends reaching corresponding ends of the module housings.

8. A battery pack comprising a battery module according to claim 1 as a unit body, wherein the battery pack comprises two or more battery modules.

9. The battery pack according to claim 8 , wherein a stack of the two or more unit battery modules is mounted in pack frames in a state in which the battery module stack is erected in a lateral direction.

10. A vehicle comprising a battery pack according to claim 8 as a power source.

11. The vehicle according to claim 10 , wherein the vehicle is an electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle.