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Super capacitors is a new type of energy storage devices, with the instantaneous release of high-current, high energy density, high charge-discharge efficiency, long cycle life, etc., can be widely used in electric vehicles, start-up and braking systems, mobile communications, information technology, aviation in areas such as aerospace and defense technology. Nickel oxide as a supercapacitor electrode material, with the typical the Faraday quasi capacitance performance, and resource-rich, low prices, and therefore become a research hotspot. In this paper a method of nano-nickel oxide composites, analysis of the prima facie evidence of microscopic structure and morphology of the products, and its electrochemical properties of the system. The main contents are as follows: (1) coordination homogeneous precipitation method successfully prepared by the different paths the two different morphologies of granular and needle-shaped nano-nickel oxide. The results show that: a particulate nickel oxide than the needle-shaped nickel oxide having a smaller ohmic resistance, a higher specific capacitance. 6 mol / L KOH electrolyte, the former than the capacitance of 203.6 F / g, approximately twice that of the latter. Nickel oxide electrode electrochemical properties of the material by the heat treatment temperature, electrolyte concentration CV scan rate and constant current charge and discharge current density. (2) was prepared by hydrothermal method to β-cyclodextrin as the template agent, nano nickel oxide, the product form of spherical particles, the particle diameter of about 5 to 8 nm. The electrochemical test results show that, the best hydrothermal reaction conditions 140 ℃ to react for 24 h. Β-cyclodextrin as a templating agent to prepare the material, reducing the degree of the agglomeration of the product, to improve the dispersibility of the product, reducing the product ohmic resistance, improve the specific capacitance of the electrode. Nickel oxide synthesis in optimal conditions than the capacitance of 196.8 F / g, 59.6% higher than non-cyclodextrin system, the internal resistance of the electrode for 0.9?, 35.7% lower than non-Cyclodextrin Systems. (3) coordination homogeneous co-precipitation prepared nano-nickel-cobalt composite oxide cobalt content of the material of electrochemical capacitor performance have a greater impact, when the cobalt mole fraction of about 65% too composite electrochemical best performance, the proportion of the complexes having a smaller ohmic resistor (1.0?), higher than the capacitance (286.9 F / g), more suitable for use in the large current charge and discharge. SEM, TEM test results also show, Cobalt-doped, the morphology of the nickel oxide changed by the accumulation of the spherical nanoparticles into nanowires stacked structure more fluffy, and having a pore structure, specific surface area of 192.176 m2 / g (19.4%) compared to a pure nickel oxide, this structure makes the composite material more easily by the electrolyte infiltration, the electrochemical reaction is to expand the effective region. Further, the inherent resistance of the composite electrode by a pure nickel oxide is 1.8? Reduced to 1.0?, Significantly improve the performance of electrochemical capacitors. The composite material has good cycling stability. (4) In the nickel-cobalt composite oxide as the cathode, with activated carbon as a negative electrode, assembling a small hybrid capacitor, experimental results show that when the mass ratio of 1:2.7 of the positive and negative, the mass ratio of the hybrid capacitor Capacitance Maximum is 56.4 F / g. Compared with symmetric capacitor, the potential window of the hybrid capacitor increased to 1.2 V, the energy density is significantly improved, and has good power characteristics and cycle stability.
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