A battery assembly for a medical device includes an elongate cathode, an elongate anode, an electrolyte, and an elongate housing assembly encapsulating the cathode, the anode, and the electrolyte. The battery assembly also includes a first electrode that is exposed from and electrically insulated from the housing assembly. One of the anode and the cathode is electrically coupled to the first electrode, and the other of the anode and the cathode is electrically coupled to the housing assembly. One of the cathode and the anode includes a first portion and a second portion disposed in spaced relationship from the first portion. The other of the cathode and the anode is disposed between the first and second portions.