Battery module

1. A battery module comprising:

at least one cell group; and

a case accommodating the at least one cell therein,

wherein the at least one cell group includes:

at least one battery cell stack formed by stacking a plurality of battery cells;

a flame retardant cover coupled to the battery cell stack to encase both side surfaces and an upper portion of the battery cell stack; and

a flame retardant member disposed between an upper surface of the battery cell stack and the flame retardant cover and formed of a porous material,

wherein the case includes:

a first plate disposed below the at least one cell group and forming a base of the case disposed under the battery cell stack and a second plate disposed above the at least one cell group, and

wherein the at least one battery cell stack is disposed in an insulation space formed by the flame retardant cover and the first plate, and

wherein the flame retardant cover extends from the first plate forming the base of the case under the battery cell stack, extends along both of the side surfaces of the battery cell stack, and extends over the flame retardant member.

2. The battery module of claim 1 ,

wherein the flame retardant cover includes side surface portions coupled to both side surfaces of the battery cell stack and an upper surface portion connecting the two side surface portions and disposed on the upper portion of the battery cell stack, and

wherein at least one gas outlet is provided on the upper surface portion of the flame retardant cover.

3. The battery module of claim 2 , wherein the at least one gas outlet is disposed in a region facing to an electrode lead of the battery cell.

4. The battery module of claim 3 , wherein the upper surface portion includes a protrusion protruding in a direction in which the electrode lead of the battery cell is disposed, and the at least one gas outlet is disposed in the protrusion.

5. The battery module of claim 1 , wherein the flame retardant cover is formed of a sheet including mica.

6. The battery module of claim 1 , wherein the flame retardant cover is formed of any one selected from the group consisting of stainless steel, graphite, graphene, carbon fiber reinforced plastics (CFRP), glass fiber reinforced plastics (GFRP), and non-woven compressible fibers.

7. The battery module of claim 1 , wherein the flame retardant member is formed as a foam pad including mica.

8. The battery module of claim 1 , wherein the flame retardant member is disposed in a compressed volume state between the battery cell and the flame retardant cover, and pressure is exerted on the battery cell through a restoring force of the flame retardant member.

9. The battery module of claim 8 , wherein

the battery cell includes an accommodating portion accommodating an electrode assembly and sealing portions disposed along a circumference of the accommodating portion, and

at least one of the sealing portions is pressurized by the flame retardant member and is in close contact with the accommodating portion.

10. The battery module of claim 2 ,

the second plate is disposed above the flame retardant cover and facing the upper surface portion of the flame retardant cover, and

the second plate includes at least one discharge hole for discharging gas formed in the battery cell.

11. The battery module of claim 10 , wherein the at least one discharge hole is disposed to not overlap with the gas outlet.

12. The battery module of claim 1 , further comprising a heat transfer member disposed between the at least one battery cell stack and the first plate.

13. The battery module of claim 12 , wherein the heat transfer member includes any one of thermal grease, a thermally conductive adhesive, and a thermally conductive pad.