Miniature lithium electrochemical cell with grooved rod-shaped cathode current collector

An electrochemical cell, comprising:

• a) a casing, comprising:
• i) a casing tube extending from a base wall to an upper annular edge, the casing tube having an outer surface spaced from an inner annular surface;
• and
• ii) a glass-to-metal seal (GTMS) comprising an insulator glass contacting a terminal pin centered inside a ferrule, wherein the ferrule is secured to the upper annular edge of the casing tube;
• and
• b) an electrode assembly housed inside the casing, the electrode assembly comprising:
• i) an anode active material contacted to the inner annular surface of the casing tube, wherein the anode active material has a tube shape forming a lumen;
• ii) a cathode current collector comprising a rod having a cylindrically-shaped outer surface extending along a longitudinal axis, wherein at least one helical groove recessed into the cylindrically-shaped outer surface of the rod turns around the longitudinal axis at a constant distance while moving parallel to the longitudinal axis, and wherein the current collector is devoid of any feature extending radially outwardly beyond the cylindrically-shaped outer surface of the rod;
• iii) a cathode comprising a cathode active material in direct physical contact with the cathode current collector, wherein the cathode has a cylindrical shape and resides in the lumen of the tube-shaped anode active materials and
• iv) a separator segregating the anode active material from directed physical contact with the cathode active material;
• and
• c) an electrolyte in the casing activating the electrode assembly,
• d) wherein the casing tube contacting the anode active material serves as an anode terminal, and wherein the cathode current collector contacting the cathode active material and being connected to the terminal pin electrically isolated from the casing tube by the GIMS serves as the cathode terminal for the cell.