Patent ID: 8642204

Claim:
A battery pack comprising: a battery module unit having a plurality of battery modules, each of the battery modules having a cell which is housed in a case and provided with a valve member for releasing gas generated in the cell into an inside of the case; a cooling air flow passage which is formed along an outer surface of the case of the battery module and in which a cooling air flow flows; and a gas exhaust duct forming a gas exhaust passage which extends in an arrangement direction of the plurality of the battery modules while the gas exhaust duct being contiguous to the battery module unit for exhausting the gas released in the case from the battery modules, and the gas exhaust duct having (a) a gas inlet for leading the gas released in the case into the gas exhaust duct, the gas inlet communicating with a gas emission hole that is provided in each case to emit the gas; and (b) at least one air intake for taking in the cooling air flow of the cooling air flow passage; and (c) a covering member that selectively opens the air intake when the cooling air flow flows, and selectively closes the air intake when the cooling air flow stops to control introduction of the cooling air flow into the exhaust duct.