| Vanadium redox flow battery is called as vanadium battery in short. Its basic principle is to achieve energy conversion by different valence vanadium ions change with redox reactions. The reactive active material is liquid vanadium ions. Its power depends on the stack and its capacity depends on electrolyte volume and concentration, which has increased the facility of the design of the battery. The standard electrode potential difference of vanadium battery is 1.25V. In actual, the battery voltage changes with the state of different charge-discharge. Vanadium battery is one kind of high-efficiency, environment friendly and high-capacity; it's also able to withstand charge-discharge with high current density and withstand depth discharge.Vanadium battery technology has developed more than twenty years. Many projects on vanadium battery were applied in the United States, Japan and Australia, which showed that vanadium battery technology was more and more mature , stepped into the early stage of large-scale industrialization. There are many factors influence the industrialization of Vanadium battery project, such as these key materials: the performance of current collector, negative electrolyte reversibility and circulation stability, the flux distribution uniformity of electrolyte in all branches and so on. The paper designed and prepared vanadium battery with high efficiency. In order to enhance the battery overall performance, the paper carried on foundational research and technology research, made the practical progress, which provided important basis for the vanadium battery industrialization production. The charge-discharge performance of vanadium battery with graphite-collector was studied. Polyethylene and Polytetrafluoroethylene conductive plastic collector were prepared. The performance of polyethylene and Polytetrafluoroethylene conductive plastic was studied. The influence of vanadium battery negative electrolyte added Toluene-p-sulfonic acid was studied. The branches flux distribution was also studied under a given flux of the main pipe.The article designed and prepared vanadium battery with 8 single cell of graphite collector and effective electrode area 784cm2. The charge-discharge performances of vanadium battery with graphite collector were studied by galvanostatic limited voltage charge-discharge test. A stable and efficient charge-discharge model of vanadium battery with graphite collector was established. The ideal charge-discharge current was 50A (63.8mA/cm2), corresponding to the columbic efficiency of 95.09% and energy efficiency of 70.79%. The charge voltage platform was from 12.8 V to 15.4V and the discharge voltage platform was from 12.2V to 10.1V with charge-discharge current from 10A to 100 A. The charge capacity decreased with higher charge current. The discharge capacity decreased with higher discharge current. The overcharge had a great impact on the vanadium battery life, so it is necessary to prevent the overcharge behavior. In order to ensure stable operation of vanadium battery, the upper limit of the charge voltage couldn't exceed 1.75V. The vanadium battery with 4 single cell of graphite collector was prepared and were studied by galvanostatic limited voltage charge-discharge test under different environmental operating temperature condition. The results indicated ideal environmental operating temperature of vanadium battery was around 26℃.The Polyethylene composite conductive plastic was prepared by mixing of HDPE, SEBS, conductive carbon black and carbon fiber et al, granulation, injection molding. The performance of the Polyethylene composite conductive plastic was studied. vanadium battery included 4 single cell with Polyethylene conductive plastic and effective electrode area 784cm2. Its performance was studied by charge-dischage test. Polyethylene conductive plastic has low-cost and could make large-scale production by injection molding. The results showed Polyethylene conductive plastic had solution impermeable, acid corrosion-resistant properties, could withstanded overcharge and had low electrochemical activity. The Polyethylene conductive plastic bulk resistivity was 0.2 ? ? cm. The SEM photograph indicated it formed the integrated electric network. The tensile strength was 47.6 MPa and elongation at break was 1.6 percent. The sample had low electrochemical activity, which accorded with the requirements of vanadium battery. Vanadium battery with Polyethylene composite conductive plastic collector could charge and discharge in charge-diacharge 50A (51mA/cm2). It could apply in the requirement of middle current density. Vanadium battery with Polyethylene composite conductive plastic collector could anti-charge. The charge anti-voltage rose very slowly and single cell voltage only achieved 0.775V.The PTFE composite conductive plastic was prepared by mixing evenly PTFE suspension, conductive filler, distilled water and dehydration, drying, being soaked with isopropyl alcohol, rolling, mould pressing, sintering processes and so on. The performance of the PTFE composite conductive plastic was studied. The result showed that the graphite power was a better conductive filler for PTFE conductive plastic than the acetylene black. The PTFE conductive plastic with 77wt% graphite dosage could form the integrated electric network, corresponding to bulk resistivity of 0.070?.cm and tensile strength of 12Mpa. The interlayer method and sintered process can increase the electrical conductivity significantly. The PTFE sample had solution impermeable, acid corrosion-resistant properties, could withstanded overcharge and had low electrochemical activity. The performances of the PTFE sample accorded with the requirements of vanadium battery.The performance of negative electrolyte with toluene-p-sulfonic acid was studied by Cyclic voltammograms method. The results showed that the performance of 2.0mol/L negative electrolyte with 0.15wt% toluene-p-sulfonic acid was the best, which could improve the catholyte reversibility and circulation stability.The flux distribution of the branche was studied under given flux of the main pipe. Many factors influenced the flux distribution of the branch, including the branch diameter, branch entrance speed, the export pressure and flow medium viscosity and so on. The results showed that the branch flux increased with the branch became far from the entrance of main pipe in medium water, the same branch diameter and full flux. When there were 15 branches, the last branch flux decreased. The branch entrance speed and export pressure weren't apparently to the flux uniformity. In full flux, The medium viscosity changed from 0.001Pa.s to 0.07 Pa.s, with the increase of medium viscosity, the flux uniformity of all branch decreased, simultaneously the branch flux increased when the same branch became near from the entrance of main pipe, the branch flux decrease when the same branch became far from the entrance of main pipe . When the number of branches increased in full flux, the diameter of the main pipe increased and the medium viscosity changed, which could increasingly affected the uniformity of the branches flux .
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