Method of producing an acid-tight joint between gas diffusion electrodes and the plastic housing of an electrochemical measuring cell

摘要

The invention relates to a method of producing an acid-tight joint between gas diffusion electrodes having a porous PTFE back layer and the plastic housing of an electrochemical measuring cell. Hitherto sealing was achieved by cementing the electrodes using a so-called acid-resistant adhesive or by using elastomeric flat seals or O-rings. A further problem is to bring the electrode contact wires out of the electrolyte chamber through the housing wall in an acid-tight manner. According to the invention, gas diffusion electrodes (4) and housing (2) are joined by thermally pressing (K) the overlapping edge (10) of the PTFE back layer (6) onto the housing (2); the electrode contact wires (8) are heated to a temperature above the softening point of the housing plastic and thereby sunk in the softened plastic. <IMAGE>