A supercapacitor based on charge storage at the interface between a high surface area carbon nanotube electrode and a Li-ClO4/PC electrolyte was assembled. The performance of the capacitor depends on not only the mate...A supercapacitor based on charge storage at the interface between a high surface area carbon nanotube electrode and a Li-ClO4/PC electrolyte was assembled. The performance of the capacitor depends on not only the material used in the cell but also the construction of the cell. From a constant charge-discharge test, the capacitance of 60 F was obtained. The performance of the power capacitor for pulse power sources was described. The specific energy (0.8 W·h·kg-1) and the specific power (0.75 kW·kg-1) of the power supercapacitor were demonstrated with a cell of the maximum operating voltage of 2.5 V. A hybrid power source consisting of a lithium ionic battery and the 60 F supercapacitor was demonstrated to power successfully a simulated power load encountered in GSM portable communication equipment. The addition of the supercapacitor to the power train of a cellular phone results in significantly more energy from the battery being used by the load. The experiments indicate that more than 33.8% energy is utilized by load and less stored energy is dissipated within the battery for each charge-discharge cycle.展开更多
A new sol-gel process for the preparation of ultrafine nickel hydroxideelectrode materials was developed. The composite electrodes consisting of carbon nanotubes andNi(OH)_2 were developed by mixing the hydroxide and ...A new sol-gel process for the preparation of ultrafine nickel hydroxideelectrode materials was developed. The composite electrodes consisting of carbon nanotubes andNi(OH)_2 were developed by mixing the hydroxide and carbon nanotubes together in different massratios. In order to enhance energy density, a combined type pseudocapacitor/electric double layercapacitor was considered and its electrochemical properties were characterized by cyclic voltammetryand dc charge/discharge test. The combined capacitor shows excellent capacitor behavior with anoperating voltage up to 1.6 V in KOH aqueous electrolyte. Stable charge/discharge behaviors wereobserved with much higher specific capacitance values of 24 F/g compared with that of EDLC (12 F/g)by introducing 60 percent Ni(0H)_2 in the anode material. By using the modified anode of aNi(OH)_2/carbon nanotubes composite electrode, the specific capacitance of the cell was lesssensitive to discharge current density compared with that of the capacitor employing pure nickelhydroxide as anode. The combined capacitor in this study exhibits high energy density and stablepower characteristics.展开更多
文摘A supercapacitor based on charge storage at the interface between a high surface area carbon nanotube electrode and a Li-ClO4/PC electrolyte was assembled. The performance of the capacitor depends on not only the material used in the cell but also the construction of the cell. From a constant charge-discharge test, the capacitance of 60 F was obtained. The performance of the power capacitor for pulse power sources was described. The specific energy (0.8 W·h·kg-1) and the specific power (0.75 kW·kg-1) of the power supercapacitor were demonstrated with a cell of the maximum operating voltage of 2.5 V. A hybrid power source consisting of a lithium ionic battery and the 60 F supercapacitor was demonstrated to power successfully a simulated power load encountered in GSM portable communication equipment. The addition of the supercapacitor to the power train of a cellular phone results in significantly more energy from the battery being used by the load. The experiments indicate that more than 33.8% energy is utilized by load and less stored energy is dissipated within the battery for each charge-discharge cycle.
文摘A new sol-gel process for the preparation of ultrafine nickel hydroxideelectrode materials was developed. The composite electrodes consisting of carbon nanotubes andNi(OH)_2 were developed by mixing the hydroxide and carbon nanotubes together in different massratios. In order to enhance energy density, a combined type pseudocapacitor/electric double layercapacitor was considered and its electrochemical properties were characterized by cyclic voltammetryand dc charge/discharge test. The combined capacitor shows excellent capacitor behavior with anoperating voltage up to 1.6 V in KOH aqueous electrolyte. Stable charge/discharge behaviors wereobserved with much higher specific capacitance values of 24 F/g compared with that of EDLC (12 F/g)by introducing 60 percent Ni(0H)_2 in the anode material. By using the modified anode of aNi(OH)_2/carbon nanotubes composite electrode, the specific capacitance of the cell was lesssensitive to discharge current density compared with that of the capacitor employing pure nickelhydroxide as anode. The combined capacitor in this study exhibits high energy density and stablepower characteristics.
