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Composite metal oxide as a new electrode material, not only has excellent capacitance characteristics, materials, and to achieve a reasonable balance of performance and cost. This article was prepared by different types of composite metal oxide by XRD, SEM, TG-DSC and XPS characterization of the physical properties of composites using cyclic voltammetry, galvanostatic charge-discharge test and AC impedance spectroscopy methods such as capacitive properties of materials a systematic study. Solid-phase reaction method (Ni-Sn) oxide, when the β-Ni (OH) 2 and SnO2 NiO conversion molar ratio of 9:1, calcining temperature of 200 ℃, the calcination time is 1h, the resulting compound nm was presented as a scaly thin stacked structure, 1mol · L -1 KOH solution, -0.2 ~ 0.3V (vs.SCE) range to 100mA · g -1 current density discharge, the discharge specific capacitance of 80.17F · g -1 . Were prepared using different type of crystal structure of MnO2, the SnO2 respectively under certain conditions with a solid phase reaction, (Mn-Sn) oxide. A molar ratio of 3:1 by KMnO4 and MnSO4 prepared by liquid phase precipitation temperature MnO2, and SnO2 at a molar ratio of 9:1, heat 2h, the resulting (Mn-Sn) oxide nano-spherical structure. The composite in 0.5mol · L -1 Na2SO4 solution, 0 ~ 1.0V (vs.SCE) voltage range, when the current density of 100mA · g -1 , the specific capacitance value of up to 291.2F · g -1 . Citrate, acetate, manganese and vanadium pentoxide by the sol-gel method (Mn-V) oxide, citric acid and manganese acetate molar ratio of 0.5:1, the pH of the reaction system is 6,400 ℃ calcined dry coagulation plastic, obtained (Mn-V) oxide thin sheet structure, the active substance in 0.5mol · L -1 Na2SO4 solution, -0.1 ~ 0.9V (vs.SCE) voltage within the specific capacitance value of up to 126.6F · g -1 . First use of KMnO4 and MnSO4 in two different molar ratios, through the liquid phase precipitation method at room temperature MnO2, respectively, and after it the V2O5 sol-gel method under different conditions by solid state reaction (Mn-V) oxide . KMnO4 and MnSO4 when the molar ratio of 2:3, MnO2 and V2O5 molar ratio of 17:1,300 ℃ heat 2h, the resulting compound in 0.5mol · L -1 Na2SO4 solution, -0.1 ~ 0.9V (vs.SCE) voltage range to 1.2A · g -1 current density discharge, the specific capacitance value of up to 161.8F · g -1 . Use of KMnO4, MnSO4 and V2O5 prepared by room temperature liquid precipitation (Mn-V) oxide, when KMnO4 and MnSO4 molar ratio of 2:3, the resulting (Mn-V) oxide nano-spherical structure, the complex in 0.5mol · L -1 Na2SO4 solution, -0.2 ~ 1.0V (vs.SCE) voltage range to 100mA · g -1 current density discharge, discharge capacity of up to 308.2F · g -1 . Cycle life test (375mA · g -1 constant current charge-discharge tests), the first discharge capacity of 248.3F · g -1 , after 180 cycles, more than capacity of 226.7F · g -1 , approximately 91.3% of the initial specific capacity.
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