Common Issues in Lithium Battery Pack Production Lines and How to Avoid Them

When setting up or operating a lithium battery pack production line, several technical and operational challenges can affect quality, efficiency, and safety. Being aware of these common issues helps buyers make better decisions and avoid costly downtime.

Cell Mismatch During Assembly

One frequent problem is pairing cells with inconsistent voltage, capacity, or internal resistance. This leads to unbalanced packs, reduced cycle life, and potential thermal issues. A reliable lithium battery pack production line should include automated cell sorting and grading before assembly to ensure only matched cells are used.

Poor Welding Quality

Busbar welding—whether laser, ultrasonic, or resistance—is critical. Weak or inconsistent welds increase resistance, causing heat buildup. To prevent this, the production line must integrate real-time monitoring, such as weld force sensors or post-weld resistance testing, especially for high-power applications.

Insufficient Testing and Traceability

Some lines skip full electrical testing or fail to link test data to individual packs. Without proper traceability, identifying root causes during field failures becomes difficult. Look for a lithium battery pack production line that includes automated testing stations (IR, OCV, BMS handshake) and stores data per serial number.

Lack of Flexibility for Different Pack Designs

Many users face difficulties when switching between pack sizes or configurations. Fixed tooling or non-modular systems require long changeover times. Choose a line with adjustable fixtures and programmable workstations to handle multiple product types efficiently.

Safety and Compliance Gaps

Improper grounding, missing short-circuit protection, or inadequate fire containment can violate safety standards like UL 1973 or IEC 62619. Ensure your lithium battery pack production line includes safety interlocks, emergency stops, and proper ventilation in high-risk areas like formation and aging stations.

By addressing these common issues early, manufacturers can improve yield, ensure compliance, and maintain consistent product quality.