Battery module having pad composite having swelling absorption and heat shielding function, battery pack comprising same and vehicle

Abstract

A battery module includes a cell stack including a plurality of battery cells; at least one composite interposed between neighboring battery cells of the plurality of battery cells; and a module case configured to accommodate the cell stack, wherein the composite includes a pair of first members configured to be compressed by a volume expansion of the plurality of battery cell caused by swelling, the pair of first members comprising a same material; and a second member interposed between the pair of first members configured to block heat transfer between the neighboring battery cells.

What is claimed is: 
     
         1 . A battery module, comprising:
 a cell stack including a plurality of battery cells;   at least one composite interposed between neighboring battery cells of the plurality of battery cells; and   a module case configured to accommodate the cell stack,   wherein the composite includes:
 a pair of first members configured to be compressed by a volume expansion of the plurality of battery cell caused by swelling, the pair of first members comprising a same material; and 
 a second member interposed between the pair of first members configured to block heat transfer between the neighboring battery cells. 
   
     
     
         2 . The battery module according to  claim 1 , wherein the pair of first members is shrunken at a reference temperature or above to a reduced thickness. 
     
     
         3 . The battery module according to  claim 2 , wherein the second member is expanded at the reference temperature or above to fill a space created by shrinkage of the pair of first members. 
     
     
         4 . The battery module according to  claim 3 , wherein the second member has an expansion rate of 5 to 40 times in a thickness direction at the reference temperature or above. 
     
     
         5 . The battery module according to  claim 1 , wherein each of the plurality of battery cells is a pouch-type battery cell. 
     
     
         6 . The battery module according to  claim 1 , wherein the composite is provided in single, and the single composite is disposed at a center of the cell stack in a stacking direction. 
     
     
         7 . The battery module according to  claim 6 , further comprising a plurality of first members respectively disposed between cell groups, each cell group including a plurality of battery cells. 
     
     
         8 . The battery module according to  claim 1 , wherein the composite is provided in plural, and the plurality of composites are respectively disposed between cell groups, each cell group including a plurality of battery cells. 
     
     
         9 . The battery module according to  claim 1 , wherein the pair of first members includes at least one selected from the group consisting of expanded polypropylene (EPP) and urethane. 
     
     
         10 . The battery module according to  claim 1 , wherein the second member has a higher density than the pair of first members. 
     
     
         11 . The battery module according to  claim 1 , wherein the second member has a higher coefficient of thermal expansion than the pair of first members. 
     
     
         12 . The battery module according to  claim 1 , wherein the second member is solid. 
     
     
         13 . The battery module according to  claim 1 , wherein the pair of first members have a reduction of thickness at elevated temperatures. 
     
     
         14 . The battery module according to  claim 1 , wherein the pair of first members have a reduction of thickness at 300° C. 
     
     
         15 . The battery module according to  claim 1 , wherein a coefficient of heat transfer of the pair of first members is higher than a coefficient of heat transfer of the second member. 
     
     
         16 . A battery pack, comprising the battery module according to  claim 1 . 
     
     
         17 . A vehicle, comprising the battery pack according to  claim 16 .