Application of Air Filters in the Lithium Battery Industry

With the rapid development of the lithium battery industry, the requirements for the production environment are becoming increasingly strict. Air filters play a crucial role in ensuring the cleanliness of lithium battery production processes, improving product quality and safety.2、 Air pollutants and hazards in lithium battery production1. Particulate matter• Source: Dust in the production environment, debris generated by equipment wear, etc.

• Harm: It may cause internal short circuits in lithium batteries, affecting their performance and lifespan, and even leading to safety accidents.2. Chemical pollutants

• Source: Chemical reagents used in the production process, equipment leaks, etc.

• Harm: It can undergo chemical reactions with the positive and negative materials of lithium batteries, affecting the electrochemical performance of the battery, reducing battery capacity and charging and discharging efficiency.

3、 Types and functions of air filters

1. Primary air filterMain function: Filter larger particles of dust, hair and other impurities, protect medium and high-efficiency filters, and extend their service life.Application scenario: It is usually installed at the air inlet of the air conditioning system to preliminarily filter the air entering the workshop.

2. Medium efficiency air filterFunction: Further filter smaller particles such as pollen, dust particles, etc., to improve the cleanliness of the air.

Application: Generally located after the primary filter, it provides cleaner air for the high-efficiency filter.

3. High efficiency particulate air filter (HEPA)Function: It can remove tiny particles with a diameter of 0.3 microns or more from the air, with a filtration efficiency of over 99.97%.

• Key applications: In the critical processes of lithium battery production, such as coating and cell assembly, ensure that the air meets high cleanliness requirements to prevent small particles from affecting battery quality.

4、 The specific application of air filters in various stages of lithium battery production1. Raw material storage and transportationTo ensure the purity of raw materials and prevent contamination, air filters are installed in the raw material storage warehouse and transportation pipeline system to prevent dust and other impurities from entering the raw materials.For example, in the storage area of raw materials such as lithium salts, air filters can filter out moisture and impurities in the air, avoiding moisture and contamination of raw materials, thereby ensuring the chemical stability of raw materials and providing basic materials for subsequent battery production.

2. Electrical manufacturingDuring the electroplating process, high air cleanliness is required. Any small particle impurities can cause uneven coating, affecting the charging and discharging performance and consistency of the battery.At this stage, air filters not only remove solid particles from the air, but also control chemical pollutants in the air, such as solvent vapors. Through an efficient air filtration system, the cleanliness of the coating environment is ensured, allowing the electric coating to be evenly and accurately applied to the current collector, improving the quality and performance of electricity.

3. Assembly of battery cellsIn the battery assembly workshop, it is necessary to prevent external dust and impurities from entering the interior of the battery cells. Air filters can create a clean production environment and reduce the impact of foreign objects on the structure and electrical performance of battery cells.For example, in the process of assembling chips, separators, etc. into battery cells, a clean air environment can reduce the risk of battery cell short circuits, improve the qualification rate and safety of battery cells. At the same time, air filters can also control the humidity and temperature in the workshop, providing suitable environmental conditions for battery cell assembly and ensuring the stability and reliability of the assembly process.

4. Battery formation and packagingDuring the battery formation process, some gas by-products are generated, which need to be promptly discharged and the environment kept clean. Air filters can filter out impurities and harmful gases in the air during ventilation, preventing them from having a negative impact on battery performance.In the packaging process, a clean air environment is also crucial for ensuring the sealing of the packaging and the appearance quality of the battery. Air filters can remove small particles that may affect the packaging quality, ensuring the reliability and stability of battery packaging, and improving the overall quality and safety of batteries.

5、 Maintenance and replacement of air filters1. Importance of MaintenanceRegular maintenance of air filters can ensure their filtration efficiency and stable performance, extend their lifespan, and reduce production costs. At the same time, maintenance can ensure the continuous cleanliness of the lithium battery production environment, reduce product quality issues and production interruption risks caused by filter failures.2. Maintenance measuresRegularly inspect the appearance of the filter to see if there are any damages, deformations, or other issues.

For primary and medium efficiency filters, surface dust and impurities can be removed by cleaning, but the number of cleaning times should be limited to avoid damaging the filter structure. High efficiency filters are generally not recommended for cleaning and should be replaced promptly based on changes in their resistance.Monitor the resistance of the air filter. When the resistance reaches a certain value, it indicates that the filter is clogged and needs to be replaced or maintained. At the same time, the filtration efficiency of the filter should be regularly tested to ensure that it can meet the cleanliness requirements of the lithium battery production environment.

3. Change frequencyThe initial filter is usually replaced every 1-3 months, depending on factors such as dust concentration in the usage environment. The replacement cycle for medium efficiency filters is usually 3-6 months. The replacement cycle of high-efficiency filters is relatively long, usually 6-12 months, but in high pollution environments or production areas with high cleanliness requirements, more frequent replacement may be necessary.Air filters are key equipment for ensuring production quality and safety in the lithium battery industry. By rational application in different production processes, pollutants in the air are removed, providing a clean environment for the production of lithium batteries. At the same time, paying attention to the maintenance and replacement of air filters can ensure their stable performance, continuous effectiveness, and high-quality development of the lithium battery industry. In the future, with the continuous advancement of lithium battery technology and the further improvement of product quality requirements, the technology and application of air filters will also continue to innovate and improve to better meet the needs of lithium battery production.