LiBF₄ powder is a lithium salt widely used in lithium battery electrolytes. It is composed of tetrafluoroboric acid (BFF₄) and lithium ions, and has good chemical stability and high ion conductivity. LiBF₄ powdercan improve the performance of the electrolyte in lithium batteries, enhance the charging and discharging efficiency of the battery, and improve the overall performance of the battery. It remains stable under extreme conditions such as high temperature and high pressure, and is currently one of the most widely used electrolyte salts in lithium batteries.

Chemical Property

Stability:LiBF₄ powder has good chemical and thermal stability, is not easy to decompose at high temperatures, and can maintain structural integrity and functional stability in environments above 200℃. It is not easy to react with moisture to generate corrosive gases and does not easily decompose to produce toxic substances.

Conductivity:It has strong ion conductivity, which can promote the rapid migration of lithium ions in the electrolyte, thereby improving the charging and discharging efficiency of the battery. Although its conductivity is slightly lower compared to LiPF₆, it can provide more stable conductivity in high humidity or special solvent systems, avoiding performance degradation caused by moisture or other impurities.

Acidity: It is a mild Lewis acid that can be used in some organic reactions

Preparation Method

1. Gas solid reaction method

Process: Place the dried LiF powder in a reactor, introduce dry BF3 gas, and react at high temperature (150-300 ℃) or high pressure.

Advantages: Simple process, no need for solvents, high product purity (up to 99% or more).

Shortcoming:BF₃ gas is highly corrosive and toxic, requiring strict sealing of equipment; It is prone to product encapsulation of unreacted LiF, resulting in incomplete reaction.

Application:Laboratory small-scale preparation or high-purity demand scenarios (such as high-end electrolytes).

2. Water solution method (wet synthesis)

Process:Slowly add lithium salts (such as Li ₂ CO ∝, LiOH) to HBF₄ aqueous solution, adjust the pH to neutral or weakly acidic, stir the reaction, filter, evaporate and concentrate, cool and crystallize, and finally dry and dehydrate.

Advantages: Mild reaction conditions, easy availability of raw materials, low cost, suitable for large-scale industrial production.

Shortcoming:The product is prone to contain crystalline water, requiring high temperature (>200 ℃) drying, high energy consumption, and may decompose; Water solutions are prone to residual impurities.

Application: Large scale production of industrial grade LiBF4 (such as lithium battery electrolytes).

3. Non aqueous solution method (organic solvent method)

Process: LiF powder is dispersed in an anhydrous organic solvent (such as ether, carbonate, hydrofluoric acid), and BF₃ gas is introduced or HBF₄ solution is added dropwise. After the reaction, it is filtered and dried.

Advantages: Avoiding water interference, low water content and high purity of the product (up to 99.5% or more), fast reaction rate.

Shortcoming: Organic solvents (such as HF) have strong corrosiveness and toxicity, and require high operational requirements; Solvent recovery is difficult, costly, and may introduce impurities.

Application: Preparation of high-purity LiBF₄ (such as solid-state battery electrolyte).

4. Double decomposition reaction method

Process: Soluble lithium salts (such as LiCl) are mixed with tetrafluoroborate (such as NaBF₄, KBF₄) aqueous solutions to generate LiBF₄ precipitate, which is filtered, washed, and dried to obtain the product.

Advantages: Mild reaction conditions, simple operation, suitable for rapid preparation in the laboratory.

Shortcoming: The product is prone to adsorb impurity ions such as Na⁺ and Cl⁻, requiring multiple washes; Low output, not suitable for large-scale production.

Application:Laboratory small-scale preparation or teaching demonstration.

5. Ion exchange method

Process:A solution containing BF₄⁻ is passed through a lithium ion exchange resin column (such as a sulfonic acid cation exchange resin), where Li ⁺ combines with BF₄⁻, and then evaporated, concentrated, crystallized, and dried to obtain the product.

Advantages: Efficient separation of impurities, high product purity, and high degree of process automation.

Shortcoming: High resin cost, requiring regular regeneration or replacement, and high operating costs; Limited processing capacity, suitable for small-scale production.

Application: Fine preparation of high-purity LiBF4 (such as electronic grade chemicals).

Storage conditions

LiBF₄ powder has hygroscopicity and should be stored in a dry, cool, well ventilated place away from sources of fire and heat. Keep the container sealed to prevent moisture. The storage area should be equipped with corresponding fire-fighting equipment and emergency response equipment for leaks.

Application

Lithium ion battery: It is an important electrolyte material for lithium-ion batteries. As an electrolyte additive, it can improve the interface layer structure of the battery, reduce charge transfer impedance, enhance battery performance and cycle life. It can also form a stable solvation structure with Li+, enhance the film-forming ability of the electrolyte on the electrode, and suppress aluminum foil corrosion. Under low temperature conditions, it exhibits better battery performance than LiPF6 and can be used to prepare long-life low-temperature lithium-ion batteries.

Organic synthesis: As a catalyst widely used in organic synthesis reactions such as esterification and alkylation, it has strong acidity and is not easily decomposed, which can effectively promote the reaction

Market

From the production end, the total global production of lithium tetrafluoroborate powder in 2024 is about 32000 tons, a year-on-year increase of 16.8%. The global market size of lithium tetrafluoroborate powder is expected to grow to 1.86 billion US dollars by 2025, a year-on-year increase of 17.7%. China occupies an important position in this market, and it is expected that China's market share will increase to 65% by 2025, with production reaching 24000 tons. In the future, with the gradual maturity of solid-state battery technology, the application scope of LiBF₄ powder is expected to further expand.