AN ELECTROCHEMICAL ROUTE FOR MAKING POROUS NICKEL-OXIDE ELECTROCHEMICAL CAPACITORS

Porous nickel oxide films were prepared by electrochemically precipita ting nickel hydroxide and heating the hydroxide in air at 300 degrees C. The resulting nickel oxide films behave as an electrochemical capac itor with a specific capacitance of 59 F/g electrode material. These n ickel oxide films maintain high utilization at high rates of discharge (i.e., high power density) and have excellent cycle life. Porous coba lt oxide films were also synthesized. Although the specific capacitanc es of these films are approximately one-fifth that of the nickel oxide films, the results demonstrate the versatility of fabricating a wide range of porous metal oxide films using this electrochemical route for use in capacitor applications.