Porous polyaniline (PANI) is prepared by using sodium dodecylsulfate as a soft template and ammonium persulfate as an oxidant. Transmission electron microscopy and nitrogen adsorption-desorption isotherms suggest the existence of both macro/mesopores and micropores, and the specific surface area of 211 m(2) g(-1). As a result of its porous structure, the porous PANI exhibits highly enhanced utilization ratio during the charge-discharge cycles. This porous PANI also displays high cycle stability and rate capability. (C) 2010 Elsevier Ltd. All rights reserved.