Patent ID: 6204635
Filing Date: 2001-03-20
Classification: H01M,Y02E

Abstract:
Current interrupt apparatus for use with an electrochemical cell having a housing with an open end and comprising a cover having a support layer receivable in the open end co-extensive therewith to close the open end of the electrochemical cell, the electrochemical cell having a positive and a negative terminal, an aperture formed in the support layer, a membrane having at least a portion formed into a cup-shaped member having a generally flat end wall, the cup-shaped member having a side wall depending from the flat end wall extending along a length to a support portion, the support portion being attachable to the support layer with the cup-shaped member being in alignment with the aperture and with the side wall extending in a direction toward the interior of the housing and with the flat end wall generally lying in a plane parallel to a plane in which the cover lies, said membrane and the support layer forming a composite in which they are co-extensive with one another and with the open end of the electrochemical cell, an electrical current path formed between an electrode within the housing and one of the positive and negative terminals, the material of the membrane being chosen to have a selected material properties so that upon being subjected to a pressure level from within the housing above a predetermined level, the side wall will catastrophically collapse with the configuration of the cup-shaped member changing to an opposite, inverted configuration with the side wall extending in a direction away from the interior of the housing and with the flat end wall continuing to lie generally in a plane generally parallel to the plane in which the cover lies, the catastrophical collapse of the side wall interrupting the current path.