Preparation And Research Of Components And Stack Of Zinc-bromine Redox Flow Battery

A battery has the advantage of highly effective, low consumption and benefiting the environment called zinc-bromine flow battery, which possess the characteristic of high energy density power and current efficiency, simple and easily operating, long service life and the capacity of thousands of times100%depth discharge. Thus it is an attractive technology for energy storage and electric vehicles.The purpose of this paper is to design and synthesis series of new type of low cost, high performance anion and cation exchange membrane material, and prepare various kinds of ion exchange membrane, and at the same time design different flow field structure of graphite double plate. Then these two kinds of key material is used to assemble the battery and battery pack in order to improve the zinc bromide battery performance and reduce costs. Specific research contents are as follows:1) To design and synthesis of new type of anion exchange membrane, the first step is to d esign and synthesis of a quaternary ammonium functional group of polymer at the same time i ts molecular structure is characterized and its properties is studied. The conduction mechanis m of the anion exchange membrane ion migration, optimization of the molecular structure of t he ion exchange membrane materials, exploring the micro structure of matching and developin g the design theory of ion exchange membrane are researched. Get a low cost, high mechanica1strength, high ionic conductivity of the new type of anion exchange membrane is prepared a nd to explore the feasibility of zinc bromide liquid flow cell as membrane.2)Use larger porosity PTFE as basal material in the process of design and synthesis the Nafion/PTFE ion exchange membrane in order to reduce the cost. Nafion solution is filled into the gap to keep its good conductivity, at the same time increase the mechanical strength and reduce the cost. The ion-structure of the synthesis Nafion/PTFE cation exchange membrane is characterized; water absorption and ac impedance is tested to optimize the molecular structure of the material in order to keep well performance in the application of zinc bromide liquid flow battery. 3)The first generation of graphite plates are designed to assemble hundreds watt zinc bromide battery stack. The first generation of bipolar plates with tube, can observe clearly of the flow of the electrolyte. The design of the second generation graphite bipolar plates is to assemble into kilowatt zinc bromide battery stack. The second generation plates increases the design of flow channel, which can be a very good guide the flow of the electrolyte. Cancelled the outer tube design, and increased the intraplate electrolyte channel design, the second generation plates make assemble battery heap more simple and beautiful. To build hundreds watt and kilowatt zinc bromide liquid flow cell stack, zinc bromide liquid flow cell are making the battery performance testing, analysis and comparison. The work compares the energy efficiency under the conditions of different charge and discharge current and discharge efficiency, and made rational design and optimization of the overall structure of the battery.