Requirements for tubing used in negative‑pole battery compressed air systems

The Role of Compressed Air in Negative-Electrode Battery Production

In the manufacturing of negative electrode materials and lithium-ion batteries as a whole, compressed air serves as an indispensable power source and process gas. It is extensively used in applications such as pneumatic valve actuation, electrode coating, pneumatic conveying of materials, and workshop environmental control. Given that the internal chemical systems of batteries are highly sensitive to impurities, the quality of compressed air directly impacts battery safety and consistency; consequently, stringent requirements are imposed on the piping materials used to convey this compressed air.

Core Performance Requirements for Compressed Air Piping Materials

• Extremely high cleanliness retention capabilityThe inner wall of the tubing must be smooth, preventing the generation, adsorption, or shedding of any particulates. Battery manufacturing requires zero tolerance for metallic particles and dust; therefore, the tubing must ensure that compressed air remains free from secondary contamination during transport.
• Excellent water- and oil-repellent performanceMoisture and oil are major adversaries in battery manufacturing. The tubing material must exhibit extremely low water‑vapor and oil permeability to prevent the ingress of external moisture or residues from the compressor unit, thereby ensuring that the air dew point meets the required specifications.
• Good corrosion resistance and chemical stabilityIn certain workshops exposed to specific chemical environments, piping materials must resist potential corrosion from chemical gases, maintain stable long-term physical properties, and remain free from rust and aging.
• Anti-static and flame-retardant propertiesIn areas where dust or flammable volatiles may be present—such as during the processing of negative electrode materials—pipes must be antistatic to prevent static charge buildup that could pose safety risks, and they must also comply with the workshop’s flame‑retardant standards.

Common Pipe Material Selection and Applications

In response to the aforementioned stringent requirements, the negative‑electrode battery workshop typically employs the following types of piping:

• Stainless steel pipeIt exhibits superior mechanical strength, corrosion resistance, and inner-wall smoothness, and is typically used in main pipelines and in critical process sections where ultra‑high cleanliness is required. The inner wall must undergo a specialized polishing treatment.
• Aluminum alloy pipe with an internal coating: Aluminum alloy tubing with a special anti-corrosion internal coating combines the advantages of lightweight construction, easy installation, and a smooth inner surface, making it well suited for branch piping networks that demand high cleanliness but operate at moderate pressures.
• High-quality engineering plastic pipe: In the connection of pneumatic actuators at the system’s end, plastic hoses that are antistatic and meet relevant certification standards are commonly used. These hoses offer excellent flexibility and do not leach harmful substances.

Key Points for Pipeline Installation and Routine Maintenance

Selecting the appropriate pipe material is only the first step; proper installation and maintenance are equally critical. During pipeline installation, seamless welding or dedicated clean‑grade quick‑connect fittings should be used, and threaded connections—prone to debris generation—should be avoided. The piping should be laid with an adequate slope, and automatic drain valves should be installed at low points to prevent condensate buildup.

During routine maintenance, it is necessary to regularly monitor the dew point and particulate concentration at the pipeline outlets. For long‑term operating pipe networks, a rigorous purging and cleaning schedule should be established to ensure that the compressed air system remains in a consistently high‑cleanliness condition, thereby providing a solid guarantee for the high‑quality production of negative‑electrode batteries.