a vehicle traction battery assembly which may include an array of battery cells is provided . each of the cells includes terminals of opposite polarity . each of the terminals may have a plurality of segment layers , and at least one of the segment layers of each of the terminals may have a melting point less than that of adjacent segment layers on either side thereof . one of the cells may be electrically isolated from other of the cells in response to at least one of the segment layers of the terminals of the one of the cells melting . the assembly may also include a housing , and the segment layers having a melting point less than that of adjacent segment layers may be located outside of the housing . the segment layers having a melting point less than that of adjacent segment layers may be located within the housing .