Industrial grade Electronic Grade Ethylene carbonate CAS 96-49-1

What is Ethylene carbonate?

Ethylene carbonate (EC) is a cyclic carbonate formed from ethylene glycol and carbonic acid. It is also one of the most important solvents in lithium-ion battery electrolytes. Its chemical formula is usually written as:

C3H4O3 (CAS No.: 96-49-1, molecular weight approximately 88.06, EINECS No.: 202-510-0)

It is a colorless needle-like or plate-like crystal at room temperature, and melts into a transparent colorless liquid above 35°C. Its melting point is approximately 35-38°C, boiling point approximately 248°C, relative density approximately 1.32-1.43, and flash point approximately 160°C. It is readily soluble in water and organic solvents such as alcohols, ethers, and ketones. Ethylene carbonate is a typical highly polar cyclic carbonate with a very high dielectric constant (approximately 90 at 40°C) and a relatively high viscosity.

From a molecular structure perspective, ethylene carbonate molecules consist of a five-membered cyclic carbonate ring, with the oxygen atom on the ring making it a highly polar solvent. Its high dielectric constant enables it to effectively dissociate and dissolve lithium salts such as lithium hexafluorophosphate (LiPF6), while its cyclic structure endows it with the ability to preferentially reduce and form a stable SEI film on the negative electrode surface—this dual function of "dissolving lithium salts + forming a film" constitutes the core basis for its widespread use in lithium battery electrolytes.

Chemically, ethylene carbonate is relatively stable at room temperature and pressure, but contact with strong oxidizing and reducing agents should be avoided. It has strong solubility in polymers, which is why it can be used as a stripping agent and cleaning agent. It should be stored in a sealed, moisture-proof container, away from open flames.

Electronic-grade ethylene carbonate refers to a high-purity product specifically designed for use in electronic chemicals (primarily lithium battery electrolytes). The following indicators are more relevant for electronic grade products than for general industrial grade products:

purity

Purity has a direct impact on electrolyte performance and battery life.

Moisture

Moisture reacts with LiPF6 to generate HF, which corrodes the electrode and damages the SEI film. This is the most critical indicator for electronic grade, and is generally required to be below 50 ppm.

Moisture reacts with LiPF6 to generate HF which erodes the electrode and damages the SEI film. This is the most important indicator of electronic grade and is typically required to be <50ppm.

Metal ion content (iron, sodium, potassium, calcium, magnesium, etc.)

Metal ions catalyze the decomposition of electrolytes. The safety of batteries needs a ppb level.

Free acid and chloride ions

The electrolyte stability and battery performance are influenced by free acid and chloride ions, which require to be controlled to very low levels.

chromaticity

It should be colorless and transparent; excessive color often indicates impurities or oxidation.

What are the uses of electronic-grade Ethylene carbonate?

1. Lithium-ion battery electrolyte solvent (core application)

Ethylene carbonate is the most important solvent component in lithium battery electrolytes. It has a high dielectric constant and can dissociate and dissolve lithium salts such as lithium hexa-fluorophosphate (LiPF6) efficiently, which has good ionic conductivity. Meanwhile, it can preferentially reduce and form a stable and dense SEI film on the surface of the negative electrode, which can inhibit the decomposition of the electrolyte and protect the graphite negative electrode. That’s what makes lithium batteries for mobile phones, electric vehicles and more so performant and long-lasting.

2. Electrolyte mixed solvent system

Electronic-grade ethylene carbonate is often compounded with chain carbonates such as dimethyl carbonate (DMC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC) to form electrolyte mixed solvents, which balance high dielectric constant and low viscosity, improve the performance of electrolytes over a wide temperature range, and meet the different application requirements of power batteries, energy storage batteries, etc.

3. High-purity electronic chemicals

The high purity of electronic-grade ethylene carbonate is suitable for the formulation of electronic chemicals such as capacitor electrolytes and electronic cleaning agents, helping to ensure the performance and reliability of electronic devices.

4. Research on novel battery technologies (research- level)

Ethylene carbonate is also an important solvent and reference system in the research of new battery systems such as solid electrolytes and sodium-ion batteries, supporting the development of next-generation energy storage technologies.

5. Chemical consumer products (indirect contact)

Ethylene carbonate is an intermediate in the synthesis of chemical products such as dimethyl carbonate (DMC), and is also used as a solvent for gas purification, desulfurization, and decarbonization. Related chemical consumer goods chains may indirectly involve it.

6. Textile products (indirect contact)

Ethylene carbonate can be used as a spinning solvent and fiber finishing agent for polyacrylonitrile (acrylic fiber), and the acrylic fabrics we wear may indirectly involve it in their spinning process chain.

7. Other Applications

With the development of the new energy industry, the application scope of electronic-grade ethylene carbonate continues to expand, including in areas such as high-purity solvent supply and lithium battery electrolyte formulation development.

It should be noted that electronic grade ethylene carbonate is extremely sensitive to moisture and metal ions. After opening, it should be sealed to prevent moisture and avoid contamination. Safety regulations should be followed during handling, and skin and eye contact should be avoided.

Summarize

Ethylene carbonate (EC) is a cyclic carbonate, which is a solid at room temperature and melts above 35°C. It is one of the most important solvents used in lithium ion battery electrolytes, because of its high dielectric constant and excellent lithium salt solubility. In our everyday life, we come into contact with it indirectly through lithium batteries in mobile phones, laptops, new energy vehicles, power tools and energy storage devices. Its production chain is also connected to the textile and chemical industries. In the domain of electronics, electronic grade ethylene carbonate is widely used as a core solvent of lithium ion battery electrolyte, a component of electrolyte mixed solvent system, a high purity electronic chemical and solvent for research on new battery technologies. It is a key high-purity electronic chemical bridging “daily use” and “new energy and electronic chemicals”.