Current collector assembly

Abstract

Collector assemblies and methods of making and using them, and electrochemical cells made with such current collector assemblies, are disclosed. The invention provides a current collector assembly which permits safe, effective venting of pressure in the cell; reduces early activation of venting structures in the current collector assembly; contains fewer piece parts than known structurally-robust current collectors; is easy to implement; and provides superior tolerance to outside impact forces. Current collectors of the invention provide a stiffer, more rigid washer, repositioned closer to the bottom plate at its central region while the washer maintains the traditional function of controlling positioning of the seal body of the current collector assembly. Increasing stiffness, rigidity, and the repositioning of the washer is accomplished by a combination of structurally sculpturing the cross-section of the washer, hardening the temper of the washer, and providing a plateau adjacent the center of the bottom plate. Washer vent holes are relocated away from the central region, the bottom plate being most vulnerable to attack in the central region. Overall, the improved washer provides both support to the seal body against outwardly-directed internal pressures within the cell and support to the bottom plate against inwardly directed impact forces from outside the cell.