Patent ID: 6737188
Filing Date: 2004-05-18
Classification: H01M,Y02E

Abstract:
An electrochemical cell, comprising:(a) a container having an open end, a closed end and a sidewall therebetween, said container comprising a separator and electrochemically active materials arranged on opposite sides of said separator; (b) a disc shaped seal body secured to the open end of said container, said seal body formed as a single component and having a top surface, a bottom surface and a perimeter contacting said top and bottom surfaces, a flexible diaphragm formed between said surfaces and positioned around a centrally located protrusion projecting perpendicularly from the center of said top surface and defining an opening between said top and bottom surfaces, said protrusion having a proximal section, a venting section and a distal section, said proximal section abutting said flexible diaphragm at a ventable interface and comprising an outer surface free of one or more indentations, said venting section concentrically aligned with and abutting said proximal section and comprising an outer surface with at least one indentation formed therein, said venting section's indentation creating an unobstructed pressure relief path along the outer surface of said venting section, said distal section concentrically aligned with and abutting said venting section; (c) a current collector extending through said opening in said protrusion and adapted to contact an electrochemically active material in said cell; and (d) an outer cover positioned between said seal body's flexible diaphragm and the cell's external environment.