Lithium-ion battery electrolytes are generally composed of lithium salts and organic solvents. The electrolyte acts as a conductor of ions between the positive and negative electrodes of a lithium-ion battery, ensuring its advantages such as high voltage and high specific energy. Electrolytes are typically prepared under specific conditions and in specific proportions from high-purity organic solvents, lithium salts, and necessary additives.
The main components of lithium-ion battery electrolyte are as follows:
1. Ethylene carbonate: Molecular formula: C3H4O3, transparent colorless liquid (>35℃), crystalline solid at room temperature, is a good solvent for polyacrylonitrile and polyvinyl chloride.
2. Propylene carbonate, colorless and odorless, or pale 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 for general low-toxicity chemicals.
3. Diethyl carbonate, colorless liquid with a slight odor; vapor pressure 1.33 kPa/23.8℃; flash point 25℃ (flammable liquid that can evaporate into vapor and enter the air).
4. Dimethyl carbonate is a non-toxic, environmentally friendly chemical raw material with excellent properties and wide applications; it also has a high evaporation temperature and a fast evaporation rate.
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-ion battery electrolytes. This product should be stored in a cool, ventilated, and dry place and transported and stored in accordance with the regulations for flammable chemicals.
6. Lithium hexafluorophosphate, white crystals or powder, deliquescent, decomposes when exposed to air or heated. When exposed to air or heated, lithium hexafluorophosphate decomposes rapidly in the air due to the action of water vapor, releasing PF5 and producing white fumes.
Precautions for using lithium battery electrolyte
1. The electrolyte tank is protected by argon gas and has a certain pressure. Do not disassemble the gas phase valve head or liquid phase valve head during use, and do not press the protrusion of the quick-release connector arbitrarily to avoid leakage or other hazards. Always wear protective goggles when connecting pipes, and always use the dedicated quick-release connector.
2. It is recommended that qualified lithium-ion battery electrolyte be used up at once. Once opened, the electrolyte is easily deteriorated due to the lack of protective atmosphere. Customers are advised to fill it with argon gas in time during use to prevent discoloration. It is not recommended to use glass containers to store the electrolyte. The main component of glass is silicon dioxide. Silicon dioxide reacts with hydrofluoric acid to produce corrosive and volatile silicon tetrafluoride gas. This gas is toxic and can cause harm to people.
3. Materials for electrolyte containers and pipes that can be used on site include: stainless steel, PP/PE plastic, PTFE, etc.
4. This product is harmful to the human body and has mild irritant and anesthetic properties. Avoid direct contact with the body during use.
Since its introduction to the market in 2002, lithium-ion battery electrolytes have gradually replaced imported products. The quality of lithium-ion battery electrolytes has also been continuously improving, and its market prospects remain broad. Although the ionic conductivity of solid-state electrolytes cannot currently match that of carbonate-based liquid electrolytes, solid-state electrolytes remain one of the mainstream research directions for future lithium-ion battery electrolytes.
