Patent ID: 7122270

Claim:
An electrochemical cell comprising a container having a bottom end and an open top end; a positive electrode disposed in the container, a negative electrode disposed in the container; a seal member disposed in the open top end of the container for closing the open top end of the container, the seal member having an opening defined by a wall; and a current collector having a shaft extending through the opening in the seal member and contacting one of the positive and negative electrodes; wherein: the current collector shaft has a surface adjacent to the seal member wall; the seal member wall has a surface adjacent to the current collector shaft; a portion of the surface of the current collector shaft is in sealing contact with at least a portion of the seal member wall when in a sealed position; at least one of the current collector shaft and the seal member wall is axially moveable from the sealed position to a vent position upon experiencing a predetermined pressure, thereby breaking at least a portion of the sealing contact to provide a pressure relief passage for venting pressurized gases between the surfaces of the current collector shaft and the seal member wall when in the vent position; and the current collector shaft comprises one or more flutes in the surface of the shaft forming at least a portion of the pressure relief passage when the current collector and the seal member wall are in the vent position.