Carbon material with its excellent performance and become one of the hot spots of the materials in the field of research, materials scientists at home and abroad around Controllable Preparation of new nano-carbon materials in supercapacitor chemical energy storage devices, to carry out a large number of research work. In support of the Chinese Academy of Sciences "Hundred and the National Natural Science Foundation of China, Lanzhou Institute of Chemical Physics of Solid Lubrication, State Key Laboratory of Yanxing Bin researcher led the research team since 2009, around the nano-carbon material in supercapacitor a series of studies designed to develop environmentally friendly, wide operating temperature, high energy density and power density of the new super capacitor the nano carbon electrode material, and achieved good results.
More recently, the research team in graphene-based supercapacitor has made new progress. The researchers investigated ion molar concentration of the liquid electrolyte, and the influence of temperature on the performance of graphene capacitance as a result, the molar concentration of the ionic liquid 2M graphene capacitor best performance. At the same time, the study results show that graphene / ionic liquid system in the temperature range of -20 ℃ ~ 60 ℃ showed good capacitance and capacitor with less dependency on the temperature.
Previously, the research team also studied the impact of the type of organic solvent and the chain length of the alkyl chain imidazolium ionic liquid cations graphene capacitance performance; addition, the research team used the self-assembly and composite technology to prepare graphene films shape memory of electrode material, and these Welding Material exhibit excellent capacitance performance.
At the same time, the research team also conducted applied research in supercapacitors based on carbon nanotubes, mesoporous carbon and carbon nanofiber Welding Electrode Material
Nickel and nickel alloys, especially the temperature of commercially pure nickel and nickel-Copper Electrode alloy, the solid-liquid phase spacing is small, low liquidity. Under welding conditions of rapid cooling and solidification crystals, some of the gaseous components in the solid phase solubility is far lower than the liquid phase, vapor phase the late precipitated to form pores in the weld metal. Nickel and nickel alloy welding carbon steel and low alloy steel welding easier to form pores, especially in the oxidation resistance welding atmosphere, more likely to produce pores. Nickel and nickel alloy of the weld metal at high temperatures will react with oxygen forming NiO, steam generated during the cooling process, with the reaction of hydrogen dissolved in the metal, with the dissolved metals react with carbon monoxide (CO) is generated in the crystalline When these gases are often too late to escape the formation of pores. Especially when dissimilar metal welding is carried out in the nickel and Nickel Alloy Welding Wire and steel, tend to be higher due to the carbon content in the steel, the amount of carbon monoxide that may produce more, the formation of pores the sensitivity may be greater. In addition, the welding in a reducing atmosphere, may also be generated by the hydrogen stomatal sensitivity. Therefore before welding on the workpiece surface removal of oxide, water, organic matter can reduce blowholes possible. Containing manganese, titanium, aluminum and other elements in the weld metal can play a deoxidizing effect. Contains chromium, manganese can improve the solubility of the gas in the solid metal, to reduce the pores can also play a beneficial effect. In order to prevent the generation of pores, you must eliminate the source of the stomata, groove and near the weld zone oxides, various coatings, grease, etc. must be removed before welding. Addition should be removed before welding of nickel and nickel alloy weldments moisture, organic matter, oxides, should pay special attention to the surface of the non-residual sulfur and leaded material to avoid weld welded joints in nickel with sulfur or lead role brittle.