Experimental and analytical techniques to determine the double-layer capacity of porous electrodes in the presence of faradaic effects are discussed. A triangular voltage sweep method was used with commercially available porous nickel plaque electrodes in KOH. No elaborate purification pretreatments were needed. A minimum double-layer capacity of about 28μF cm2 was determined at −0.40 V versus Hg/HgO which is close to the pzc reported for nickel. Overall the results agreed well with literature values for solid nickel.