BATTERY MODULE, BATTERY RACK, AND POWER STORAGE DEVICE

A battery module that reduces the risk of secondary ignition or explosion is provided. The battery module includes a plurality of cell assemblies including a plurality of secondary batteries; a module housing including an accommodation space configured to accommodate the plurality of cell assemblies; and a blocking member configured to, when a gas pressure more than a predetermined gas pressure or a heat more than a predetermined temperature is generated in at least some cell assemblies among the plurality of cell assemblies, block the generated gas or heat from moving to the other cell assemblies.