To build a 18650 manufacturing line, you need to have knowledge in the following areas:

1. Structure and working principle of 18650 batteries: Understand the internal structure, electrode materials, electrolytes, and the working principle and performance characteristics of 18650 batteries.

2. Material and supply chain management: Familiarize yourself with the properties and characteristics of electrode materials, electrolytes, separators, and other key materials. Understand supply chain management, supplier selection, and quality control.

3. Battery production processes: Master the production processes involved in manufacturing 18650 batteries, including material preparation, electrode manufacturing, battery assembly, formation, testing, and packaging, along with the key operational and control points.

4. Equipment and technology: Learn about the equipment and technologies required for 18650 battery manufacturing, including electrode coating machine, winding machines, assembly equipment, formation equipment, testing equipment,battery analyser, packaging equipment, and related automation and control systems.

5. Quality control and testing: Understand the quality control requirements for 18650 batteries, including testing methods and standards for capacity, voltage, internal resistance, cycle life, and the quality control processes and measures.

6. Safety and environmental requirements: Familiarize yourself with the safety and environmental requirements in the battery manufacturing process, including safety operating procedures, waste management, and material storage and handling considerations.

7. Automation and intelligent manufacturing technologies: Understand the current applications of automation and intelligent manufacturing technologies in the battery manufacturing industry, such as robotic operations, data analysis, and monitoring systems.

8. Regulations and certifications: Acquire knowledge about the regulations and certification standards applicable to the battery manufacturing industry to ensure compliance with relevant laws, regulations, and international standards.

9. Cost management and efficiency optimization: Learn about cost management, production efficiency optimization, and quality improvement methods and strategies to enhance production efficiency, reduce costs, and ensure product quality.

10. Market demand and trends: Understand the demand for 18650 batteries in sectors such as electric vehicles, energy storage systems, and portable electronic devices. Stay updated on market trends and developments to guide product positioning and marketing efforts.

Having knowledge in these areas will help you understand and plan a comprehensive 18650 battery manufacturing line, enabling you to remain competitive in the market.