A Study On The Synthesis, Characterization And Properties Of High Surface Area Carbon Supports NiO Supercapacitor Materials

Supercapacitor is a new energy storage equipment and component between batteries and electrostatic capacitors, which has higher energy density than that of electrostatic capacitor and higher power density than that of batteries. When working with batteries, they can meet the high power out-put need of electric vehicles when starting-up or accelerating. It can also be applied into many field such as hybrid electric vehicle, fuel cell mobile telephone and microcomputer. According to the principle of energy-storage there are two types of capacitors: electric double-layer capacitor and faradaic pseudocapacitor. Electrode material mainly includes carban matetial, metal oxide and conducting polymei.In this paper,the nano nickel oxide particles have been prepared by direct precipitation method with NiSO4 as materials and NaOH as the precipitating agent. The nano nickel oxide particles were mixed with BP2000 activated carbon powder with a ratio of 75:25 to prepare NiO / C composite material capacitance by mechanical milling. X-ray diffraction(XRD) and transmission electron microscopy (TEM) showed the performance of the composite materials, crystal type and morphology. The cyclic voltammetry, galvanostatic charge-discharge and AC impedance have study the performance of its super-capacitance.The NiO / C capacitor material possesses several advantage such as small particle size (30nm), good dispersion, crystal integrity, simple processing and good prospects for industrial application. In this paper, the impact of the morphology of the capacitance material, particle size and electrochemical properties of the material load capacitance with the heat treatment temperature have been researched. The impact amonge the electrolyte concentration, current density of charging and discharging have been discussed, and the influence of the mechanical milling conditions to the material particle size, structure and performance capacitance were studied.The results showed that the performance and the capacitance is the best by heated 2h when the temperature is 300℃. NiO in the KOH solution possesses a good performance of super capacitors; When the loading concentration is 5mg/cm2 and the charge current is 10mA/cm2, the more the concentration of KOH is, the more its capacitance is. When the concentration of KOH increased to 2mol / L, the capacitance of NiO / C would increase not obviously. In the 2mol / L KOH solution, if the charge current is large, the capacitance performance is better when the loading of NiO/C is 5 mg/cm2 compared with 10 mg/cm2. The particle size of the NiO/C composite materials decreased from 30nm to 15nm after mechanical milling 20h. The capacitance increased from 89.2F / g to 175.3F / g when the current density is 5mA/cm2. The equivalent series resistance of the electrochemical reaction decreased from2.122? to 1.097?, The capacitance is 150.2F / g and faded15.1% after the cycle of 1000 times under the 5mA / cm2 current density.