A battery pack includes a plurality of battery cells each having positive and negative cell terminals and a carrier mounted over and spanning across the plurality of battery cells. The carrier has trays with openings therethrough exposing the positive and negative cell terminals. A plurality of buss bars are received in corresponding trays. The buss bars each have a positive plate laser welded to the positive cell terminal of a corresponding battery cell through the corresponding opening and a negative plate laser welded to the negative cell terminal of a different battery cell through the corresponding opening. The buss bars may be bimetal buss bars.