industrial grade Battery grade 99.5% Diethyl carbonate CAS 105-58-8 DEC

What is diethyl carbonate? What are the applications of electronic grade diethyl carbonate?

1. What is Diethyl carbonate?

Diethyl carbonate (DEC) is an ethanol carbonate, belonging to the chain carbonate family. It is also an important co-solvent in lithium battery electrolytes. Its chemical formula is usually written as:

C5H10O3 (CAS No.: 105-58-8, molecular weight approximately 118.13)

It is a colorless, transparent liquid at room temperature with a slightly pungent odor (ether-like smell). Its melting point is approximately -43°C, boiling point approximately 126.8°C, relative density 0.975, refractive index 1.3846, and flash point (closed cup) approximately 32.8°C. Diethyl carbonate is insoluble in water but miscible with most organic solvents, including alcohols, ketones, esters, and aromatic hydrocarbons.

From a molecular structure perspective, diethyl carbonate molecules consist of a carbonate group (OC(=O)-O) linked to two ethyl groups, belonging to a symmetrical chain carbonate class. Its low viscosity is a core advantage that makes it a key component in electrolytes: when combined with high-dielectric-constant cyclic carbonates (such as ethylene carbonate), it can significantly reduce the overall viscosity of the electrolyte, improve lithium-ion transport and low-temperature performance—this "low-viscosity co-solvent" function forms the basis for its widespread use in lithium-ion battery electrolytes (as an important component of electrolyte mixed solvents).

Chemically, diethyl carbonate is relatively stable, but flammable (flash point approximately 32.8°C). Its vapor can form explosive mixtures with air, so it must be kept away from sources of ignition. It is incompatible with strong oxidizers and strong reducing agents. It should be stored in a sealed, fire-proof, and moisture-proof container.

Electronic-grade diethyl carbonate refers to a high-purity product specifically designed for use in electronic chemicals (primarily lithium battery electrolytes). Compared to standard industrial-grade diethyl carbonate, electronic-grade products place greater emphasis on the following indicators:

purity

lectronic grade electrolytes generally require a purity of 99.99% or higher.The purity directly affects the performance of the electrolyte and the life of the battery, electronic grade electrolytes generally require a purity of 99.99% or higher.

Moisture

Moisture reacts with lithium hexafluorophosphate (LiPF6) to produce HF, which corrode the electrode and damage the SEI film . The most important indicator for electronic grade and generally required to be less than 50ppm.

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

Metal ions at ppb level can accelerate the electrolyte decomposition and influence battery safety.

free acid and chlorid ions

Free acid and chloride ions

Free acid and chloride ions affect the stability of the electrolyte and battery performance, and must be controlled at extremely low levels.

Color

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

What are the uses of electronic-grade Diethyl carbonate?

1. Co-solvent for lithium battery electrolyte (core application)

Diethyl carbonate is an important co-solvent in lithium battery electrolytes. Due to its low viscosity, when combined with cyclic carbonates such as ethylene carbonate (EC), it can reduce the overall viscosity of the electrolyte, increase the lithium-ion migration rate, and significantly improve the low-temperature performance and rate performance of the battery. It is a key component in the electrolyte formulations of lithium batteries for mobile phones, electric vehicles, and other applications.

2. Electrolyte mixed solvent system

Electronic-grade diethyl carbonate is often compounded with ethylene carbonate (EC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), etc., to form electrolyte mixed solvents, which take into account high dielectric constant, low viscosity and wide temperature range performance to meet the different application requirements of power batteries, energy storage batteries and other applications.

3. High-purity electronic cleaning solvent

Diethyl carbonate is soluble in a wide variety of polymer material. High purity electronic grade products can be used for precision cleaning of electronic components, helping to remove processing residues, ensuring the performance and reliability of electronic devices.

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

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

5. Paints and inks (indirect contact)

Diethyl carbonate is a green and environment friendly solvent. It is used as a solvent for materials such as nitrocellulose, resins, etc. It indirectly plays a role in the production of eco-friendly paints, inks and cleaning agents.

6. Other Applications

With the development of the new energy industry, the application scope of electronic-grade diethyl 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 diethyl carbonate is extremely sensitive to moisture and metal ions. After opening, it should be sealed to prevent moisture and contamination. Safety regulations should be followed during handling, and it should be kept away from fire sources and avoid skin and eye contact.

Summarize

Diethyl carbonate (DEC) is a colorless, transparent, chain-like carbonate liquid with low viscosity and high solubility. It is an important co-solvent and environmentally friendly solvent for lithium-ion battery electrolytes. In daily life, we indirectly come into contact with it through the chain of lithium batteries in mobile phones, laptops, new energy vehicles, and environmentally friendly coatings. In the electronics field, electronic-grade diethyl carbonate is widely used as a co-solvent for lithium-ion battery electrolytes, a component of electrolyte mixed solvent systems, a high-purity electronic cleaning solvent, and a solvent for research on new battery technologies. It is a key high-purity electronic chemical that connects "daily use" with "new energy and electronic chemicals."