A nonaqueous electrolyte battery that includes a unit cell and a battery case that encloses the unit cell. The battery case includes a laminate film that encloses the unit cells by heat welding at least a portion of the laminate film. Upon heat welding, the unit cell further includes a number of electrode terminal leads in which a portion of the electrical terminal leads extend from the battery case. A sealant layer is further applied to at least a portion of the electrode terminal leads so as to contact the battery case upon heat welding in order to further seal the case and to further prevent short circuiting of the nonaqueous-electrolyte battery.