Hermetically sealed primary electrochemical cell and a method for its production

A method of producing a hermetically sealed primary electrochemical cell comprising the steps of:

• forming an electrically conductive hollow outer casing having a single opening therein;
• placing an anode of a selected electrochemical system within the outer casing and in mechanical and electrical contact with the outer casing so that the outer casing forms one terminal of the primary electrochemical cell;
• placing a cathode of the selected electrochemical system and a separator of non-conducting material within the outer casing so that physical contact between the anode and cathode materials is prevented;
• filling the outer casing with an effective amount of an electrolytic solution compatible with the selected electrochemical system, said electrolytic solution including a solvent and a solute dissolved therein;
• placing a layer of barrier material in sealing contact with the inner wall of the casing to temporarily seal the electrolytic solution from the casing opening;
• inserting a glass-to-metal seal into the opening in the outer casing, the glass-to-metal seal having a solid metallic feedthrough in the central portion thereof which engages the cathode material upon insertion and which serves as a current collector therefor;
• and
• welding the glass-to-metal seal to the outer casing to form a hermetic seal, the temporary seal generally preventing volatilization of electrolyte during the welding step.