| The super-ionistor is a new type of electrochemical energy storage devices between the typical rechargeable batteries and the typical dielectric capacitors and have advantages of both of them. The typical dielectric capacitors can provide high power densities and have very long cycle life, but they have low energy densities. The typical rechargeable batteries can provide high energy densities, but have low power densities and short cycling life. Super-ionistors can meet both the power and the energy requirements for such systems as acceleration power for electric vehicles, burst power for the generation of electronic devices and so on, and have drawn more and more attention in recent years. The dissertation focus on the preparation, structure, properities of electrode material and mechanism of forming capacitance of super-ionistors utilizing carbon nanotube(CNT) and nickel oxide(NiO) electrodes. The main results are as follows.1. Films of nickel hydroxide are electrochemically precipitated on nickel substrate and then annealed in air to obtain films of nickel oxide. The effect of annealing temperature of Ni(OH)2, electrolyte solution and doped cobalt on the properties of pseudocapacitance of nickel oxide electrode material is studied. The mechanism of forming capacitance is also discussed. Of them, the nickel oxide film doped with cobalt and cerium is proposed as an electrode material of super-ionistor for the first time. The results show that specific capacitance decreases when the annealing temperature increases from 250 癈 to 500 "C because the size of crystallite of nickel oxide is enlarged and the amount of crystallite boundary is reduced. Nickel oxide film electrodes behave pseudocapacitance in aqueous KOH but behave double layer capacitance in LiClOVPC . The specific capacitance is enlarged when cobalt is doped into nickel oxide as a result of the increasing of lattice defects of nickel oxide. A specific capacitance of 280 F/g is achieved when using nickel oxide films doped with cobalt as electrodes and Imol/L aqueous KOH as an electrolyte.2. The properties of super-ionistors utilizing carbon nanotube electrodes are studied. The effects of reflux treatment, electrolyte solution and the diameter of carbon nanotube on the properties of electrodes are investigated. The BET area increases by 52 percent and the specific capacitance increases by 170 percent after reflux treatment. When carbon nanotubes refluxed by acid are used as electrodes and 30% H2SO4 is used as the electrolyte, super-ionistors with specific capacitance of 102F/g and good frequency response are obtained. For this type of super-ionistors, there is not only electric double layer capacitance, but also pseudocapacitance.HI3. A composite electrode material comprising carbon nanotubes and nickel oxide is obtained when carbon nanotubes refluxed with nitric acid are employed as base material and coated with nickel hydroxide sol, then fired at 400 ℃ for 2h. This CNT/NiO material is proposed and applied as an super-ionistor electrode material for the first time. The structure and morphology of this composite material are analyzed. The effect of refluxing treatment of acid and adding of nickel oxide to carbon nanotubes on the properties of super-ionistors is also studied. The results show that there is not only electric double-layer capacitance but also pseudocapacitance for super-ionistors based on this composite electrode material. The super-ionistors can also achieve high power and good frequency response ability. When the weight percent of nickel oxide in the composite is 50%, the specific capacitance of super-ionistors is 160 F/g. Percolation phenomenon is observed in the composite material.4. AC impedance analysis is employed to study frequency-response characteristic of super-ionistors utilizing carbon nanotube and activated carbon block electrodes. The frequency-response characteristic about carbon nanotube electrodes is studied for the first time. Charge saturation for super...
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