METHOD OF DIRECT RESISTANCE WELDING - SELF BRAZING OF ALUMINUM TO MOLYBDENUM PIN

摘要

A direct welding process for joining a current collector to a terminal pin in the construction of electrochemical cells is described. The resistance welding process utilizes increased current combined with an applied force to bond dissimilar metals with a melting temperature differential of preferably more than 500° C. Preferably, the method is used to bond the terminal pin to the cathode current collector. This method of attachment is suitable for either primary or secondary cells, particularly those powering implantable biomedical devices.

主权项

1. A method of providing an electrochemical cell, comprising the steps of:
a) providing a first electrode including a first electrically conductive current collector of a first metal comprising a main body portion supporting at least one first electrode active material thereon and an extending tab not contacted by the first electrode active material; b) providing a header assembly comprising a casing lid including an aperture surrounding an insulating material supporting a terminal pin of a second metal having a length extending between spaced apart proximal and distal ends, wherein the terminal pin is in non-conductive relation with the lid; c) contacting the proximal end of the terminal pin to the tab positioned between first and second welding electrodes; d) welding the distal end of the terminal pin to the current collector tab by applying an electrical current between the first and second welding electrodes while simultaneously applying a force directed to the contact relationship between the terminal pin and the tab; e) electrically associating the first electrode with a second, counter electrode having a separator disposed therebetween as an electrode assembly housed inside a open ended container; f) securing the lid to the open end of the container to thereby provide a closed casing housing the electrode assembly; and g) activating the electrode assembly with an electrolyte filled into the casing.