US Patent 7879478 Battery module and method of manufacturing the same

A battery module comprises: first and second rechargeable batteries, each of which includes a casing for storing an electrode assembly and a cap assembly provided on top of the casing; an interconnector provided between an upper portion of the first rechargeable battery and a lower portion of the second rechargeable battery so as to connect the first and second rechargeable batteries with each other; and an insulation cover which covers interconnected portions of the first and second rechargeable batteries, and which has at least one ventilation outlet.