Does lithium battery factory use air compressor?
Official explanation on the application of air compressors in lithium battery production
In the field of lithium battery manufacturing, compressed air systems, as key infrastructure, run through core processes such as pole piece manufacturing, cell synthesis, and chemical composition and capacity. After systematically reviewing the industry’s practices and technical characteristics, the following professional explanations are given on the specific application and quality assurance system of air compressors in lithium battery production:
1. Application of core process links
- Pole piece manufacturing process
- Air flow transportation: A closed pipeline transportation system is used to realize the automated transfer of positive and negative active substances, conductive agents and other materials through compressed air, reducing manual intervention and increasing production capacity by more than 30%.
- Slurry treatment: In the homogenization process, compressed air drives an ultrasonic degassing device to efficiently remove bubbles and moisture in the slurry and ensure coating quality.
- Pole piece drying: During the baking process, compressed air cooperates with the thermal cycle system to maintain the oven temperature stability of ≤±2℃ and ensure that the moisture content of the pole piece is ≤500ppm.
- Cell synthesis stage
- Winding control: Control the winding tension through a precision pressure regulating valve to ensure that the alignment between the positive and negative pole pieces and the diaphragm is ≤0.5mm to avoid the risk of short circuit.
- Liquid injection protection: After electrolyte injection, compressed air vacuum breaking technology is used to maintain the pressure difference between inside and outside the cell ≤0.02MPa to prevent shell deformation.
- Seal test: Use compressed air to conduct airtightness test, test pressure ≥0.4MPa, leakage rate ≤1×10 Pa·m³/s.
- Chemical composition and capacity process
- Power supply: Provide stable air source for testing equipment such as formation cabinets and sub-capacity cabinets, and the pressure fluctuation range is controlled within ±0.05MPa.
- Environmental maintenance: In the drying room, compressed air drives the dehumidification system to maintain the dew point ≤-60℃ to ensure the chemical stability of the cell.
2. Special process guarantee plan
- Vacuum process support
- Homogenate protection: Equipped with a dedicated vacuum pump, driven by compressed air, to maintain the vacuum of the slurry preparation environment ≤-90kPa to prevent impurities from being mixed in.
- Pole piece processing: In the lamination process, a high-flow central vacuum system is used, which increases the utilization rate of suction area by 22%, ensuring that the pole piece position accuracy is ≤0.1mm.
- Nitrogen preparation system
- Sintering protection: Provide high-purity nitrogen gas for roller kiln sintering of lithium iron phosphate cathode materials, with oxygen content ≤5ppm to prevent material oxidation.
- Welding protection: When welding the top cover of the cell, nitrogen is used as the protective gas, and the flow stability is ≤±2L/min to avoid oxidation of the weld.
3. System configuration and quality control
- Air Treatment Standards
- Cleanliness requirements: Equipped with a three-level filtration system to ensure that the dust content of compressed air is ≤0.01μm and the microbial index is ≤10CFU/m³.
- Dew point control: Adopt a combination process of freezing dryer and adsorption dryer, and the pressure dew point is stable below-60℃.
- Oil content control: The total oil content is controlled to ≤0.01ppm through precision filters and activated carbon adsorption devices.
- Gas supply guarantee system
- Dual machines in parallel: Configure main and standby units, and the automatic switching time is ≤30 seconds when a single unit fails to ensure continuous production.
- Intelligent control: It adopts pressure sensors and frequency conversion drives to automatically adjust the operating frequency of the unit according to the air load, and the energy-saving efficiency is improved by more than 22%.
- Monitoring system: Install online monitoring terminals to display pressure, temperature, dew point and other parameters in real time, and set three-level alarm thresholds.
4. Typical application cases
- A power battery enterprise project
- Configuration plan: 4 centrifugal air compressors (single displacement 8300 m ³/h) are used, equipped with cold drying machines, dry cleaners and precision filters.
- Operation effect: The system pressure stability is ≤ ± 0.02MPa, and the dew point is ≤-60 ℃, meeting the production demand of 50,000 tons of lithium iron phosphate materials per year.
- Energy efficiency performance: Through high-compensation and low-interlock adjustment, the energy-saving efficiency is increased by 22% compared with traditional solutions, and the air compression station building was rated as a first-class energy efficiency.
- Consumer Electronics Battery Project
- Configuration plan: Adopt screw air compressor (displacement 350 m ³/h), equipped with vacuum pump and nitrogen generator.
- Operating effect: The dust content of compressed air is ≤ 0.01 μ m, the purity of nitrogen is ≥ 99.999%, and the self-discharge rate of the cell is guaranteed to be ≤ 2%/month.
- Maintenance management: Implement a preventive maintenance system, extend the filter element replacement cycle to 8000 hours, and increase the overall equipment efficiency (OEE) to 92%.
It is recommended that lithium battery manufacturing companies establish a compressed air quality management system, including document control procedures such as equipment ledgers, maintenance records, and test reports. Conduct a compressed air system risk assessment every year and use FMEA tools to identify potential risk points. For new projects, CFD simulations should be carried out to optimize the layout of the pipe network, avoid dead spots with low flow velocity, and ensure the quality of gas supply from the design source. Through refined operation management, system energy efficiency is maximized while ensuring high product quality.