Patent ID: 8703309

Claim:
A battery pack comprising: a battery cell having an electrode assembly of a cathode/separator/anode structure mounted in a battery case made of a metal material together with an electrolyte in a sealed state; an insulative mounting member having openings, through which electrode terminals of the battery cell are exposed to an outside, the insulative mounting member being constructed in a structure in which a protection circuit module (PCM) is mounted to a top of the insulative mounting member, the insulative mounting member being in direct contact with a top of the battery cell; a positive temperature coefficient (PTC) element electrically connected to the electrode terminals of the battery cell and the PCM; and an insulative cap coupled to the top of the battery cell such that the insulative cap surrounds the insulative mounting member while the PCM is mounted to the insulative mounting member, wherein the PTC element is constructed in a structure in which a first connection plate for electrical connection with the battery cell and a second connection plate for electrical connection with the PCM are coupled to opposite major surfaces of a PTC body, the first connection plate being constructed in the shape of a plate, the first connection plate being directly coupled to a top of the battery case by welding, while the first connection plate is not bent, such that the first connection plate is electrically connected to the top of the battery case, wherein the first connection plate is constructed in a clad metal structure in which a part facing the battery cell is made of the same material as the battery case, the first connection plate being coupled to the battery case by resistance welding, wherein the first connection plate has a size greater than that of the PTC body and the second connection plate such that the first connection plate is coupled to the top of the battery case by welding, and a portion of the first connection plate extends beyond a perimeter of a protection circuit board of the PCM when viewed from above, wherein the second connection plate is a nonvariable nickel plate, which is coupled to the PCM by a surface mounting technology, and wherein the battery cell is provided at the top thereof with at least one coupling groove, and the insulative mounting member is provided at a bottom thereof with at least one coupling protrusion corresponding to the at least one coupling groove, whereby coupling of the insulative mounting member to the battery cell is accomplished by insertion of the at least one coupling protrusion into the at least one coupling groove.