Preparation And Performace Modification Of UV-Curable SPE Materials

With the increasing requirement for environmental protection in the world, the battery technology is coming into the era of Green Environmental Protection. As the lithium polymer secondary battery, which has been popular from 1990's, has some good natures, such as cleanness, high voltage, high energy density, long cycle life, easy made etc., it will probably replace lead acid-type, nickel hydrogen-type, and even lithium ion-type battery.In this paper, polyethylene glycol diacrylate (PEGDA), a kind of matrix oligomer, was synthesized, using a solid acid as a catalyst in place of sulphuric acid. Other reaction conditions, such as solvent type, alchol acid ratio, temperature, reaction time, and ion-conductivity and mechanical performance of final made electrolyte was compared when using two different solid acids. On the other hand, the modification of electrolytes was carried out with PEGDA as a crucial materials.Firstly, the effects of crossing density, copolymerization of polyurethane acrylate with PEGDA, hybrid UV curing of PEGDA with cationic UV-curable monomer on conductivity, mechanical performanceand UV curing velocity of solid polymer electrolytes (SPE) materials were discussed. It was found that the suitable crossing density and types of copolymers would be beneficial to improving the mechanical performance of the matrix, and increasing the conductivity without decreasing the UV curing velocity, and that hybrid UV curing had some disadvantages to the conductivity and UV curing, and was unsuitable to be used, although it could improve the mechanical performance thereof in some degree.Next, the effects of plasticizers and nanopowders on the UV curing, conductivity and mechanical performance were mainly researched. It was concluded that plasticizers could greatly improved the conductivity, but had some adverse effects on the mechanical and UV curing performance, and that the particle type, the particle size, and the processing method of the surface of the nanopowder would influence the properties of the SPE materials. During the research, we found that TiO2 could greatly increase the conductivity, but it was unsuitable to be used in the UV curing system, and A12O3 with a particle size of 27nm could improve the conductivity and the mechanical performance of SPE materials without obvious side-effects on UV curing, and it was preferable.Finally, base on the above research, ortho test with PEGDA which was synthesized by solid acid, polyurethane acrylate (PUA), PC+3EC, A12O3 as factors, and the contents of them as the level, were carried out,and obtained the preferable embodiment which was PEGDArPUA: PC+3EC:A12O3= 1:0.3:0.2:0.02.