Abstract: This invention relates to an electrochemical cell comprising a cathode containing a proton-conducting compound as an electrode active material, an anode containing a proton-conducting compound as an electrode active material and an aqueous electrolytic solution containing a proton source as an electrolyte, wherein the electrolytic solution comprises a polymeric compound having an atom with an unpaired electron in its principal chain as an electron-transfer promoter. This invention can provide an electrochemical cell exhibiting improved capacity, high-speed charge/discharge properties and cycle properties.

Abstract: This invention provides an electrode comprising a porous conductive substrate as well as an electrode active material and a conductive auxiliary filled in the pores in the substrate. This electrode exhibits improved shape stability (strength), a lower resistivity and better response. This electrode can be used to provide an electrochemical cell capable of quick charge/discharge and exhibiting improved cycle properties.