Main composition, lithium battery electrolyte electrolyte composition

The main components of lithium battery electrolyte, and the harm of electrolyte components. The electrolyte of a lithium battery is the carrier of ion transport in the battery, and plays a role in conducting ions between the positive and negative electrodes of the lithium battery. It is like a "love bond" between the positive and negative electrodes, ensuring that the lithium ion battery obtains advantages such as high voltage and high specific energy. What are the main components of lithium battery electrolyte? What are the hazards of electrolyte components?

Main components of lithium battery electrolyte

Currently, the main electrolytes used for lithium batteries on the market include lithium perchlorate, lithium fluoride salts, and lithium hexafluorophosphate. Batteries made of lithium perchlorate have poor low-temperature performance and a risk of explosion, and have been banned in Japan and the United States. The battery made of lithium fluoride salt has good performance, no explosion risk, and strong applicability. The battery made of lithium hexafluorophosphate has good performance, no explosion risk, and strong applicability. In the future, the disposal of waste batteries is relatively simple, and it is environmentally friendly. Therefore, the battery made of lithium hexafluorophosphate has a broad market prospect.

Electrolytes are generally prepared from high-purity organic solvents, lithium salts of electrolytes, necessary additives, and other raw materials under certain conditions and in a certain proportion.

Its main components include the following seven types:

Vinyl carbonate: Molecular formula: C3H4O3, transparent and colorless liquid (>35 ℃), crystalline solid at room temperature, and a 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, dry place, away from ignition sources, and stored and transported in accordance with general regulations for low toxic chemicals.

3. Diethyl carbonate, colorless liquid, slightly odorous; Steam pressure 1.33kPa/23.8 ℃; Flash point 25 ℃ (flammable liquid can evaporate into vapor and escape into the air.

Dimethyl carbonate is a non-toxic, environmentally friendly, and widely used chemical raw material; At the same time, it has higher evaporation temperature and faster evaporation speed.

5. Methyl ethyl carbonate, a colorless transparent liquid, is a high-tech and high value-added chemical product emerging in recent years. It is an excellent solvent for lithium battery electrolyte. This product should be stored in a cool, ventilated, and dry place, and stored and transported in accordance with the regulations for flammable chemicals.

6. Lithium hexafluorophosphate, white crystal or powder, with strong deliquescence; When exposed to air or heated, lithium hexafluorophosphate decomposes rapidly in the air due to the action of water vapor, emitting PF5 and generating white smoke.

Phosphorus pentafluoride is a phosphorus halide compound. Phosphorus pentafluoride is a colorless odorous gas at normal temperature and pressure, which has a strong irritation to the skin, eyes, and mucous membranes. Phosphorus pentafluoride is used as a catalyst for polymerization reactions.

Electrolyte composition hazards

There are two types of electrolyte for lithium batteries, one is acidic, and the other is alkaline. The main component of the electrolyte is sulfuric acid, and the other is sodium hydroxide. Both of them have strong corrosivity, and their harm is self-evident.

1. Health hazard, invasive route: inhalation, ingestion, percutaneous absorption.

Health hazard: Diethyl carbonate is a mild irritant and anesthetic. Inhalation can cause headache, dizziness, weakness, nausea, breathing difficulties, etc. Liquids or high concentration vapors are irritant. Oral irritation of the gastrointestinal tract. Prolonged repeated contact with the skin can cause irritation.

2. Radiation: The so-called radiation refers to the phenomenon that radio frequency waves generated by high-frequency oscillations of circuits emit into space. Radiation at a certain frequency and intensity has an impact on the body.

3. The working environment of lithium batteries may contain many harmful elements, some mercury elements are relatively common, as well as other lead elements. Causes heavy metal diseases.

4. Generates white corrosive and irritating hydrogen fluoride fumes in humid air. Decomposition in water releases highly toxic and corrosive gases. Decomposition in the presence of alkali.

5. Protective measures

Respiratory system protection: When the concentration in the air is high, it is recommended to wear a self priming filter type gas mask (semi mask).

Eye protection: Wear safety glasses.

Body protection: Wear antistatic work clothes.

Hand protection: Wear rubber gloves.

Others: Smoking is strictly prohibited at the work site. After work, take a shower and change clothes. Pay attention to personal hygiene.

Lithium battery electrolyte can mainly cause poisoning (accidental ingestion), chemical corrosion, and mechanical damage to human organs. Be careful when using, avoid direct contact with the skin as much as possible, and avoid entering the eyes and swallowing by mistake, otherwise the consequences will be unimaginable. We have seen the power of such things in chemical laboratories. In particular, concentrated sulfuric acid can instantly carbonize organic substances such as cellulose and glucose. Skin cells are also composed of a large number of organic compounds, so once contacted, the consequences must be serious.

Electrolyte has a significant impact on the overall performance of lithium ion batteries. As the blood of lithium ion batteries, electrolyte bears the heavy responsibility of transporting lithium ions. Its quality will directly affect the performance of lithium ion batteries. The materials of lithium battery electrolyte need to be tested and selected, and after mixing the ingredients, it is also necessary to carefully operate during the batch production process. After all, electrolyte also has a significant impact on the performance and safety of lithium batteries.