Lithium battery electrolyte main components
Lithium battery electrolyte is the carrier of ion transmission in the battery. It plays the role of conducting ions between the positive and negative electrodes of the lithium battery, just like the "love bond" between the positive and negative electrodes. Guarantee of high specific energy and other advantages. So what are the main components of lithium battery electrolyte?
Lithium batteries currently on the market mainly use electrolytes such as lithium perchlorate, lithium fluoride, and lithium hexafluorophosphate. Batteries made of lithium perchlorate do not work well at low temperatures, and there is a danger of explosion. Japan and the United States have banned their use. The battery made of fluorine-containing lithium salt has good performance, no danger of explosion, and strong applicability. Batteries made of lithium hexafluorophosphate, in addition to good battery performance, no explosion hazard, and strong applicability, the disposal of waste batteries in the future is relatively simple and environmentally friendly, so batteries made of lithium hexafluorophosphate have a broad market prospect.
The electrolyte is generally prepared from high-purity organic solvents, electrolyte lithium salts, necessary additives and other raw materials under certain conditions and in a certain proportion.
It has the following seven main components:
1. Ethylene carbonate: Molecular formula: C3H4O3, transparent colorless liquid (>35°C), crystalline solid at room temperature, good solvent for polyacrylonitrile and polyvinyl chloride.
2. Propylene carbonate, colorless and odorless, or light yellow transparent liquid, soluble in water and carbon tetrachloride, miscible with ether, acetone, benzene, etc. This product should be stored in a cool, ventilated and dry place, away from fire sources, and stored and transported according to the regulations of general low-toxic chemicals.
3. Diethyl carbonate, a colorless liquid with a slight odor; vapor pressure 1.33kPa/23.8°C; flash point 25°C (flammable liquid can volatilize into vapor and run into the air.
4. Dimethyl carbonate is a non-toxic, environmentally friendly and widely used chemical raw material; it also has a high evaporation temperature and a fast evaporation speed.
5. Ethyl methyl carbonate, a colorless and transparent liquid, is a high-tech, high-value-added chemical product that has emerged in recent years. It is an excellent solvent for lithium battery electrolytes. This product should be stored in a cool, ventilated, and dry place. Store and transport according to the regulations of flammable chemicals.
6. Lithium hexafluorophosphate, white crystal or powder, strong deliquescence; decomposes when exposed to air or heated, lithium hexafluorophosphate decomposes rapidly in the air due to the action of water vapor when exposed to air or heated, releases PF5 and produces white smoke.
7. Phosphorus pentafluoride is a phosphorus halide compound. Phosphorus pentafluoride is a colorless and malodorous gas at normal temperature and pressure, which is highly irritating to the skin, eyes and mucous membranes. Phosphorus pentafluoride is used as a catalyst for the polymerization reaction.
