Elongate battery for implantable medical device

A method of operatively coupling a medical device to a patient comprising:

• operatively coupling a lead of the medical device to a biological tissue of the patient;
• implanting a control assembly and a battery assembly of the medical device within the patient, the battery assembly defining an axis, the battery assembly including an elongate cathode, an elongate anode, an electrolyte, an elongate housing assembly encapsulating the cathode, the anode, and the electrolyte, and a first electrode exposed from and electrically insulated from the housing assembly, the housing assembly, the cathode and the anode being substantially coaxial, one of the anode and the cathode being electrically coupled to the first electrode and the other of the anode and the cathode being electrically coupled to the housing assembly, and the cathode and the anode being coaxial and spaced apart in a direction substantially parallel to the axis;
• supplying power from the battery assembly to the control assembly;
• and
• controlling electrical signal transmission through the lead.

A battery assembly for an implantable cardiac device that is implantable in a biological tissue comprising:

• a cylindrical cathode;
• a cylindrical anode;
• an electrolyte;
• a substantially cylindrical housing assembly enclosing the cathode, the anode, and the electrolyte, the cathode and the anode being coaxial and spaced apart in a direction substantially parallel to the axis;
• and
• a first electrode exposed from and electrically insulated from the housing assembly, one of the anode and the cathode being electrically coupled to the first electrode and the other of the anode and the cathode having an outer surface that abuts an inner surface of the housing assembly to electrically couple to the housing assembly.