Cylindrical Battery Module Assembly Line

A Cylindrical Battery Module Assembly Line is a specialized production system designed to process thousands of individual cylindrical cells (such as the 18650, 21700, or 4680 series) into high-voltage battery modules.

Unlike prismatic lines that handle larger blocks, cylindrical lines prioritize high-speed handling and precision electrical connectivity due to the massive number of connection points (welds) required.

Core Stages of the Assembly Line

Cell Loading & Testing: Cells are automatically loaded from trays and passed through high-speed testing stations to check Open Circuit Voltage (OCV) and Internal Resistance (ACIR). Only cells with matching profiles are grouped together to ensure pack balance.

• Cell Cleaning: Automated plasma cleaning or laser cleaning is applied to the cell terminals (positive and negative caps) to remove oxidation or contaminants, ensuring a high-quality weld.
• Bracket Insertion & Glue Dispensing: Cells are inserted into plastic or composite spacers (brackets). Automated dispensers apply thermal interface material (TIM) or structural adhesive to secure the cells and manage heat dissipation.
• Busbar / Nickel Strip Placement: A Cell Contact System (CCS) or precision-cut nickel/copper strips are placed over the cell array.
• Wire Bonding or Spot/Laser Welding: * For smaller cells (18650/21700), ultrasonic wire bonding or micro-spot welding is common.
• BMS Integration & Housing: The Battery Management System (BMS) and sensors are installed, and the module is enclosed in its outer casing.
• EOL (End-of-Line) Testing: Every module undergoes a final battery test (charging/discharging) and a Hi-Pot (high potential) insulation test to ensure safety and performance.