BATTERY PACK

A battery pack includes a battery module including a module housing and a plurality of battery cells accommodated in the module housing; a pack housing accommodating a plurality of battery modules therein and having at least one venting hole for discharging gas externally from the pack housing; a transverse member installed in the pack housing and disposed in a direction, intersecting an internal space of the pack housing; and a flow guide member disposed in an internal space of the transverse member in a longitudinal direction of the transverse member, and configured to guide gas introduced from a transverse portion connection hole in the transverse member, to form a first gas flow with directionality in the longitudinal direction of the transverse member.