Abstract: A battery module is provided with a battery cell stack and a module case. The battery cell stack includes a plurality of stacked flat secondary battery cells. The module case includes an inwardly protruding section, a low rigidity section and a high rigidity section. The inwardly protruding section is disposed on at least one of two oppositely facing sides of the module case that faces in a battery cell stacking direction and protruding toward the interior area of the module case to apply pressure to an end surface of the battery cell stack. The low rigidity section elastically supports a periphery of the inwardly protruding section due the low rigidity section having a lower rigidity than the inwardly protruding section. The high rigidity section supports a periphery of the low rigidity section with the high rigidity section having a higher rigidity than low rigidity section.

Abstract: A battery module is provided with a battery cell stack and a module case. The battery cell stack includes a plurality of stacked flat secondary battery cells. The module case includes an inwardly protruding section, a low rigidity section and a high rigidity section. The inwardly protruding section is disposed on at least one of two oppositely facing sides of the module case that faces in a battery cell stacking direction and protruding toward the interior area of the module case to apply pressure to an end surface of the battery cell stack. The low rigidity section elastically supports a periphery of the inwardly protruding section due the low rigidity section having a lower rigidity than the inwardly protruding section. The high rigidity section supports a periphery of the low rigidity section with the high rigidity section having a higher rigidity than low rigidity section.