a battery module having improved interconnection members to connect rechargeable batteries together and to minimize an increase in a volume of the battery module includes : first and second rechargeable batteries , each having an electrode assembly including a first electrode , a second electrode , and a separator interposed therebetween , and a casing to contain the electrode assembly ; a first interconnection member arranged on an upper side surface of the casing of the first rechargeable battery and electrically connected to the first electrode of the first rechargeable battery ; and a second interconnection member arranged on a lower side surface of the casing of the second rechargeable battery and electrically connected to the second electrode of the second rechargeable battery , the second interconnection member being connected to the first interconnection member .