High-purity 99% Lithium Nitrate CAS 7790-69-4 LiNO₃

What is Lithium nitrate? How does it work?

Lithium nitrate (LiNO3) is a white crystalline salt that combines the properties of lithium ions and nitrate oxidation. It serves as a molten salt heat storage medium in solar thermal power plants, stabilizes the electrolyte in lithium-sulfur batteries, and is the source of the red flame in fireworks—making it a versatile lithium salt used in modern new energy, building materials, fireworks, and fine chemicals.

Basic identification information: Molecular formula LiNO3, molecular weight 68.95, CAS number 7790-69-4, EINECS number 232-218-9, HS code 28342990, UN 2722 (Class 5.1 Oxidizing solids, Packaging Category III).

Physically, lithium nitrate is a white trigonal crystal that is hygroscopic; its density is 2.38 g/cm³; its melting point is 264℃; its boiling point is 600℃ (decomposes); it is extremely soluble in water (approximately 70.1 g/100 mL at 20℃, reaching 175 g/100 mL at 60℃), and soluble in ethanol, pyridine, and ammonia; its aqueous solution is neutral to slightly alkaline (pH 7-9).

Chemically, lithium nitrate is a strong oxidizing agent (Hazard Class 5.1): nitrate ions decompose at high temperatures, releasing oxygen, which may cause combustion upon contact with combustibles, reducing agents, or metal powders (hazard code R8); lithium ions, however, endow it with unique "lithium effects," such as reducing melting point in molten salts, inhibiting alkali-aggregate reaction in concrete, and stabilizing electrolytes. It is stable when heated with water but incompatible with strong acids and organic matter. Storage must be airtight and moisture-proof, away from combustibles and reducing agents.

From the perspective of its mechanism of action, lithium nitrate plays an irreplaceable role due to the "oxidizing power of nitrate ions + the characteristics of lithium ions". The mechanism of action in different applications is as follows:

1.Molten salt melting point reduction mechanism (multi-component eutectic system)

Lithium nitrate has a melting point (264℃) lower than that of sodium nitrate (308℃) and potassium nitrate (334℃). When it is combined with NaNO3/KNO3 in a certain proportion to form a multi-element eutectic salt, the melting point can be reduced to the range of 120-200℃, which widens the liquid working temperature window and improves the specific heat capacity and heat transfer efficiency of the molten salt. It is a key component of molten salt for solar thermal storage.

2.Nitrate oxygen-donating oxidation mechanism

Nitrate ions (NO3-) decompose at high temperatures to release active oxygen, providing an oxidant for combustion and propulsion reactions; lithium ions give the flame a characteristic red color (the flame color reaction of lithium), and have the dual function of "oxygen supply and combustion support + red coloration", making them an ideal choice for oxidants in fireworks and propellants.

3.Lithium-ion inhibition mechanism (ASR control in concrete)

Lithium ions can react with alkali silica gel to form stable lithium silicates with low solubility and low expansion, which can inhibit the expansion and cracking of alkali-aggregate reaction (ASR) in concrete. Lithium nitrate is a commonly used lithium source for lithium-based ASR inhibitors since it is a readily soluble lithium salt that disassociates fully and is easy to add.

4. Interface stabilization mechanism of lithium-sulfur batteries (SEI and polysulfide suppression)

LiNO3 can be reduced in lithium-sulfur battery electrolytes to form a stable nitrogen-containing SEI film on the lithium anode surface to suppress the decomposition of the electrolyte. It can also react with dissolved polysulfides to relieve the “shuttle effect”, which greatly enhances the coulombic efficiency and cycle life of lithium-sulfur batteries.

5.Moisture absorption and dissociation mechanism (drying/antistatic)

Lithium nitrate, with its powerful hygroscopic properties, can absorb moisture from the environment, thus dehumidifying and drying. In the aqueous solution of lithium nitrate, there are lithium ions and nitrate ions. The ionic conductivity of lithium nitrate gives the substance antistatic properties. That layer of ions on the surface after moisture absorption can carry static charge away.

In summary, lithium nitrate is a typical representative of "oxidizing lithium salts". With the combination of the oxidizing properties of nitrate and the characteristics of lithium ions, it has applications in many fields, from solar thermal storage to lithium-sulfur batteries, from fireworks to concrete, including new energy, building materials, fireworks and fine chemicals.

What are all the uses of Lithium nitrate?

1.Molten salt thermal storage and heat transfer medium for solar thermal power generation (core application in the new energy field)

Application Field: Solar thermal electricity generation (CSP), industrial heat transfer and energy storage

Corresponding Products: Ternary molten salt (LiNO3-NaNO3-KNO3) thermal storage medium; molten salt storage tanks and heat exchange systems for tower/trough CSP plants; heat transfer fluids for industrial waste heat recovery

Applicability Principle: Lithium nitrate (264℃) melts at a lower temperature than sodium nitrate/potassium nitrate. It can greatly decrease the freezing point of molten salt and enlarge the liquid operating temperature window after multi-element eutectic processes. At the same time, it enhances the specific heat capacity and thermal stability of the molten salt, enabling CSP plants to produce electricity at night. It is a key part of next-generation high temperature molten salt thermal storage.

2.Lithium-sulfur battery electrolyte additives (main application in lithium battery domain)

Application Field: Lithium-Sulfur (Li-S) Batteries and Next Generation High Energy Density Batteries

Corresponding Products: Electrolytes for Li-S batteries, high energy density battery systems, interface stabilization formulations for Li metal batteries

Applicability Principle: LiNO3 is reduced on the surface of the lithium anode to form a stable nitrogen-containing SEI film that can prevent the decomposition of the electrolyte, and react with the dissolved polysulfides to alleviate the "shuttle effect", which greatly improves the coulombic efficiency and cycle life of lithium-sulfur batteries. It is an essential additive for lithium-sulfur battery electrolytes.

3.Concrete alkali-aggregate reaction inhibitor (core application for a variety of building materials)

Application Field: Concrete Engineering and Building Materials

Corresponding Products: Lithium concrete admixtures, ASR (Alkali-Silica Reaction) inhibitors, hydraulic dam and bridge concrete anti-cracking formulations

Applicability Principle: Lithium nitrate has high solubility and can release lithium ions completely. Lithium ions can react with alkali-silica gel and form low-expansion and stable lithium silicate, which inhibits alkali-aggregate reaction and prevents concrete from cracking. It is a common lithium source for lithium-based ASR inhibitors (together with lithium hydroxide and lithium carbonate) suitable for long-life concrete projects.

4.Oxidants for fireworks and signal flames (fireworks industry)

Application Field: Fireworks industry and signaling equipment

Corresponding Products: Red fireworks/confetti shells, signal flares, torches and lighting flares, stage fireworks

Applicability Principle: Lithium nitrate is both a nitrate oxidant (decomposes at high temperatures to release oxygen and aid combustion), and its lithium ions produce a characteristic red flame reaction during combustion. It serves two purposes, making it a classic oxidant and colorant for red flame fireworks products.

5.Liquid ammonia stabilizer for refrigeration systems (refrigeration industry)

Application Field: Cryogenic engineering, refrigeration industry

Corresponding Products: Ammonia refrigeration systems (cold storage, ice storage), liquid ammonia stabilizer, absorption refrigerant systems

Applicability Principle: Adding lithium nitrate to liquid ammonia can inhibit the decomposition and corrosive side reactions of ammonia, stabilize refrigerant performance and prolong the system life. It is a commonly utilized stabilizing additive for ammonia refrigeration systems.

6.Glass etchants and phosphor raw materials (electronic optics field)

Application Field: Electro-optics and display lighting

Corresponding Products: Glass etching solution (display panel/optical component processing), phosphor (energy-saving lamp/monitor/scintillator), optical glass modification

Applicability Principle: Lithium nitrate solution can gently etch glass surfaces for precision machining; its lithium ions entering the phosphor matrix can improve luminous efficiency and color purity, making it an important lithium source for electro-optical materials.

7.Ceramic flux (ceramic industry)

Application Field: Ceramic industry

Corresponding Products: Ceramic glazes and fluxes, special ceramics, electronic ceramics, enamel

Applicability Principle: Lithium ions have small radii and high electric field strength. Lithium nitrate (or its decomposition products) lowers the sintering temperature, refines grains, and improves thermal expansion matching in ceramic formulations, making it a commonly used lithium component for ceramic flux modification.

8.Molten salt baths and heat treatment media (metallurgical industry)

Application Field: Metallurgical and heat treatment industries

Corresponding Products: Metal quenching/annealing salt baths, non-ferrous metallurgical molten salt electrolyzers, metal surface treatment molten salts

Applicability Principle: Nitrate molten salt baths use lithium nitrate. The uniform heat transfer and thermal stability of the molten salt are used in quenching, annealing and other heat treatments of metals. At the same time, lithium ions may improve the performance of the molten salt, and they are a commonly used component in metallurgical molten salt systems.

9.Desiccant and dehumidifier (drying and dehumidification domain)

Application Field: Air drying, industrial drying

Corresponding Products: Lithium salt system liquid dehumidifying air conditioning dehumidification solution, industrial gas desiccant, moisture-absorbing desiccant

Applicability Principle: Lithium nitrate is very hygroscopic, readily absorbing water from the surrounding atmosphere. The aqueous solutions of lithium salts are very efficient moisture-absorbing components in liquid dehumidifying air conditioning and industrial drying systems because of their low vapor pressure, strong moisture-absorbing ability and regenerability.

10.Antistatic agents (textile, electronics industries)

Application Field: Textile industry and electronics manufacturing

Corresponding Products: Antistatic coating/film, antistatic treatment agent for electronic devices, antistatic finishing agent for textiles

Applicability Principle: Lithium nitrate aqueous solution has ionic conductivity, containing lithium ions and nitrate ions. Applying it on the surface of materials creates a conductive ionic layer which drains away static electricity, thereby preventing damage to electronic devices and textiles from static electricity build-up.

11.Reagents for analytical chemistry (scientific research field)

Application Field: Scientific research, test analysis

Corresponding Products: Analytical grade/high-purity lithium nitrate reagents, lithium standard solutions and spectroscopic analysis reagents

Applicability Principle: Lithium nitrate is highly soluble, can be obtained in high purity and contains lithium in a stable form and is therefore used as a standard reagent for the elemental analysis of lithium and for spectroscopic and chromatographic analysis. It is also a very common raw material for materials and battery research.

12.Raw material for production of lithium salts and lithium compounds (lithium chemical industry)

Application Field: Chemicals and fine chemicals of lithium

Corresponding Products: Other lithium salts (including high purity lithium carbonate and lithium phosphate), lithium-based fine chemicals and specialty lithium compounds

Applicability Principle: Lithium nitrate is an important intermediate raw material for the preparation of various lithium compounds. Due to its easy solubility and decomposition, lithium nitrate can provide lithium ions to the target products through reactions such as metathesis and thermal decomposition.

In general, lithium nitrate (LiNO3, CAS 7790-69-4) is a typical representative of the “oxidizing lithium salts”. According to its nitrate oxidizing properties and lithium ion characteristics, it has mature applications in solar thermal molten salt storage, lithium-sulfur battery electrolyte additives, concrete ASR suppression, fireworks oxidizers, propellants, ammonia refrigeration stabilizers, glass etching and phosphors, ceramic fluxing, metallurgical molten salt baths, drying and dehumidification, antistatic agents, analytical reagents, and lithium salt production. It has multiple functions such as reducing the melting point of molten salt, providing oxygen, developing color, suppressing lithium ions and stabilizing interface, which makes it an irreplaceable lithium salt in new energy and special industries.