Experimental Research On Synthesis And Properities Of3,5-bis(Dicyanomethylene) Croconate Electrolyte For Lithium-ion Batteries

So far, the most important aim in the chemical electrical energy filed is to explore storage battery with high energy and long life. In1859, Gaston Plante invented Lead Acid storage battery firstly. In1980, Armand put forward idea about lithium ion battery with rocking-chair character, which has promoted applications and developments of lithium ion storage battery. The lithium-based compound with rocking-chair character can take the place of lithium anode materials in storage battery. It not only incarnates the advantage of high working voltage, but also greatly overcomes security problem of lithium ion battery. Moreover, it can improve cycle life of battery. Thus, lithium ion battery with rocking-chair character is a kind of new chemical green energy and high-powered-tech industries of the state giving full support. Lithium ion storage battery has great application prospect and economic benefit in many fields including electric vehicle, portable electronic products and national defence industry and so on. In recent years, it becomes the hot spot of research in battery field. Electrolyte is the main component part of lithium ion. So its performance is very important. This paper mainly introduces the synthesis and studying situation of electrochemical properties of electrolyte of3,5-methylene cyanide lithium croconate electrolyte for lithium-ion batteries. The main contents of the study are as follows:1. The direction of the paper is summarized based on a lot of documents. A series of croconate acid derivatives are chosen and designed to prepare lithium salt.2. A series of boron lithium salt were designed and synthesized: Lithium[1,3-(dicyanomethylene)croconate]-[1,2-benzenediolate(2)-o,o’]borate, lithium[3,5-(dicyanomethylene)croconate]-[3-fluoro-1,2-benzenediolate(2)-o,o’]borat e,lithium[3,5-(Dicyanomethylene)croconate]-[3,4,5,6-fluoro-1,2-benzenediolate(2)-o, o’] borate. The structures of the compounds are characterized by FT-IR, ICP,IR and NMR. 3. The thermodynamics and electrochemistry properties of the newly prpepared lithium salt and lithium boron lithium salt are studied, including solubility, thermal stability, electric conductivity and oxidation potentials.