The Application of Gas Mixing Machine in the Production of Lithium Iron Phosphate for Positive Electrodes of New Energy Batteries
1. Background of Application
Lithium iron phosphate (LFP) is an important positive electrode material for lithium-ion batteries, widely used in electric vehicles and energy storage systems due to its high safety, low cost, and long cycle life. In the production process of lithium iron phosphate, it is necessary to mix lithium iron phosphate with precursors (such as hydroxylated nickel cobalt manganese or hydroxylated cobalt) to adjust the performance indicators of the final product.
2. Advantages of Gas Mixing Machine
The gas mixing machine uses a pure gas force stirring method without mechanical stir rods, which has the following advantages:
- Avoid material damage: Traditional mechanical stirring may cause lithium iron phosphate and precursor particles to break or deform, while gas stirring does not produce mechanical stress on the material.
- High efficiency and uniformity of mixing: The vortex effect of the gas flow can achieve rapid and uniform mixing of materials, ensuring consistent product performance.
- Low dust dispersion: Dust dispersion during gas stirring is minimal, meeting the no-dust workshop requirements.
- Easy cleaning and maintenance: The device structure is simple, with no easy-to-damage mechanical parts, making cleaning and maintenance more convenient.
3. Specific Application Scenarios
In the mixing of lithium iron phosphate with precursors, the gas mixing machine can be applied to the following two processes:
1) Dry Mixing Method
- Process flow:
- Lithium iron phosphate powder and precursor powder are separately fed into the mixing machine through the feeding system.
- The mixing machine uses gas (such as inert gas or compressed air) for stirring to thoroughly mix the two materials.
- The mixed product is collected via the discharge system for subsequent processes (such as calcination, grinding, etc.).
- Features:
- Simple process, no need for additional liquid additives, suitable for direct mixing of lithium iron phosphate and precursors.
- High mixing efficiency and uniformity.
2) Wet Mixing Method
- Process flow:
- Lithium iron phosphate powder and precursor powder are mixed with water or other solvents to form a suspension or slurry.
- A gas mixing device is used to mix the slurry, ensuring that particles are dispersed and uniformly distributed.
- The mixed slurry can be dried by spray drying or used for pelletization in subsequent processes.
- Features:
- Suitable for scenarios where high dispersion of lithium iron phosphate and precursors is required.
- Gas mixing avoids the particle aggregation issues that traditional mechanical stirring might cause.
4. Industry Pain Points and Solutions
1) Industry Pain Points:
- The mixing of lithium iron phosphate and precursors requires high uniformity and dispersion, which traditional mechanical stirring devices are unable to meet effectively.
- Mechanical stirring may cause particles to break or dust to fly, affecting product quality.
- Mixing efficiency is low, unable to meet large-scale production demands.
2) Solutions:
- Utilize gas mixing machines to achieve efficient and uniform mixing through the vortex effect of gas flow, avoiding mechanical stirring-induced material damage and dust issues. The device's design without mechanical stir rods reduces equipment failure rates and meets continuous production requirements.
5. Application Cases
- Case 1: Mixing lithium iron phosphate with nickel cobalt manganese hydroxide precursor using a dry method.
- Gas mixing machine is used to mix lithium iron phosphate (LFP) powder with nickel cobalt manganese hydroxide (NCM) precursor powder, achieving uniform mixing.
- The mixed product undergoes calcination and grinding to produce high-performance positive electrode materials.
- Case 2: Wet mixing of lithium iron phosphate with cobalt hydroxide precursor.
- In the wet process, gas mixing machine ensures that lithium iron phosphate and cobalt hydroxide slurry is uniformly mixed.
- The slurry is spray dried and then used to produce high-capacity positive electrode materials.
6. Performance Indicators
- Mixing efficiency: Quickly reaches a uniform mixing state, suitable for large-scale production requirements.
- Uniformity of mixing: ≥99% (can be adjusted according to customer needs).
- Maintenance: No mechanical wear parts, maintenance is simple and long-term.
- Dust control: Meets environmental protection requirements, reducing workshop pollution.
- Energy efficiency and high efficiency: The installed power of the machine is low, with a comprehensive energy-saving effect of about 60%.
7. Conclusion
The gas mixing machine demonstrates significant advantages in the mixing of lithium iron phosphate with precursors, effectively meeting the process requirements for new energy battery positive electrodes in terms of high uniformity, low damage, and high efficiency. Its design without mechanical stir rods not only reduces equipment failure rates but also enhances production efficiency and product quality, making it an ideal solution for the new energy battery industry.
Case Study: Mixture of Lithium Iron Phosphate (LFP) and Nickel Cobalt Manganese Hydroxide (NCM) Precursors
Background Information
- Client: A lithium iron phosphate positive electrode material production plant
- Annual Production Capacity: 50,000 tons
- Process Requirements: Uniform mixing of lithium iron phosphate powder with nickel cobalt manganese hydroxide precursors to produce high-performance positive electrode materials.
Challenges Faced
1. Inhomogeneous Mixing: Traditional mechanical stirring devices cannot achieve high uniformity.
2. Low Efficiency: Long mixing times, unable to meet large-scale production demands.
3. High Maintenance Costs: Mechanical stirring devices are prone to wear and tear, with frequent maintenance needs.
Solution
Adopt a gas-mixing method for dry mixing of lithium iron phosphate (LFP) and nickel cobalt manganese hydroxide (NCM) precursors. The following details the process flow and technical specifications:
Process Flow
1. Feeding System:
- Lithium iron phosphate powder and nickel cobalt manganese hydroxide precursors are fed into the mixing machine using gas-assisted conveying or vibration feeder.
- The feeding process employs a closed design to prevent dust leakage.
2. Gas Supply:
- Inert gas (e.g., nitrogen) is used as the stirring medium to prevent oxidation reactions.
- Gas flow rate and pressure can be adjusted based on material properties to ensure thorough mixing.
3. Mixing Process:
- High-speed gas flows within the mixing machine generate turbulent effects, enabling rapid and uniform mixing of the two materials.
- Mixing time is typically 10-15 minutes, ensuring high efficiency.
4. Discharge and Collection:
- The mixed product is collected through appropriate discharge methods.
- Dust control measures are implemented to ensure a clean working environment.
Equipment Configuration
- Mixing Machine: Designed for homogeneous blending of powders with precise temperature control.
- Dust Control System: Includes filters and ventilation systems to maintain a clean production area.
- Gas Supply System: Ensures consistent inert gas availability for optimal mixing conditions.
Performance Metrics
1. Uniformity: Achieves >99% uniformity in powder mixture, verified through particle size analysis.
2. Throughput: Capable of handling up to 50,000 tons annually with a single unit.
3. Energy Efficiency: Reduces energy consumption by minimizing unnecessary stirring operations.
4. Environmental Compliance: Meets all relevant environmental regulations and safety standards.
Cost Benefits
- Reduced Waste: Consistent product quality minimizes scrap rates.
- Lower Operational Costs: Minimizes labor requirements and energy usage.
- Extended Equipment Lifespan: Reduces wear and tear from traditional mechanical stirring.
Conclusion
Through the use of gas-mixing technology for dry blending of lithium iron phosphate (LFP) and nickel cobalt manganese hydroxide (NCM) precursors, we effectively address the inefficiencies of traditional mechanical methods. This approach ensures high uniformity, energy efficiency, and environmental compliance while significantly enhancing positive electrode material performance and production efficiency.
