Effect of Clamping Pressure and Temperature on the Performance of a CuCl(aq)/HCl(aq) Electrolyzer

Abstract

A significance performance limitation for a CuCl(aq)/HCl(aq) electrolytic cell is the ohmic losses associated with the contact resistance. The contact resistance between the flow field channels of the end plate and the carbon cloth electrodes plays a significant part in ensuring good electrical connection. The contact resistance is heavily dependent on the clamping pressure, and despite the link between compressionandelectrochemicalperformance,therearenopublished results related to optimum amount of pressure needed to assemble a CuCl(aq)/HCl(aq) electrolytic cell. While insufficient clamping pressuremayresultinhighelectricalresistanceattheelectrodes/flow-field channel interface, a high clamping pressure could lead to mechanical deformation of the MEA and uneven pressure distribution. An excessive compression pressure also increases the mass transport problems with a reduction in cell performance at high current densities. 9,10 In this study, an optimum value of the compression pressure resulting from torque on the bolts that clamp the cell was observed to be 20 Nm. Also, this study highlights the increase in performance of a CuCl(aq)/HCl(aq) electrolyzer by increasing the temperature from 40 to 80 ◦ C.