Shengchuang Intelligent Technology (Guangdong) Co., Ltd

Home > Company News > Comprehensive Analysis of the Complete Production Process of lithium-Ion Battery Pack Assembly Line
News

Comprehensive Analysis of the Complete Production Process of lithium-Ion Battery Pack Assembly Line

Battery Pack Assembly Line
 
Battery Pack: The "Heart" of New Energy Vehicles
 
The battery pack includes multiple aspects as the battery pack production and manufacturing is a quite complex process. Battery pack production includes installation & connection, covering, & testing.
In the Installation and connection stage, first, the box will be cleaned, then glued, followed by putting the connectors and thermal management system components inside the box, while finally, the modules or battery cell modules will be placed and fixed inside the box.
 
_20250410152039
 
1. Battery cell sorting - OCV testing
The sorting of lithium-ion battery PACK is aimed at guaranteeing performance consistency and improving safety. By selecting battery cells or modules with similar performance and other parameters, it can ensure that the battery pack can stably output power under various work conditions, and accurately estimate the cruising range. Also, the consistency of the battery cells and the resistance against the protection circuit can prevent overcharge or over discharge, reduce the risk of short-circuit, and avoid safety accidents or performance variations due to abnormal individual battery cells or modules. Thus, it establishes a solid basis for the stable and efficient operation of new energy equipment.
 
_20250410152043
 
2. Remove dust and dirt - plasma cleaning
The role of plasma cleaning in the production of power battery PACK really lies in removing surface contaminants on battery cells, increasing the surface energy to enhance adhesion, improving electrochemical performance, reducing safety hazards, preparing for the gluing process, being eco-friendly and pollution-free, and improving the uniformity and consistency of cleaning. This will improve the overall performance and reliability of the battery.
 
_20250410152141
 
3. Battery bonding and fixing - battery cell gluing
The main function of gluing in power battery PACK is to assure fixation and sealing between battery cells, between the battery cells and module structure, and between the module and battery pack shell. This improves the structural stability of the battery pack. The glue will also protect against the displacement of the battery cells under vibration or impact, provide the necessary electrical insulation, and protect against water and dust. Thus, it improves the overall safety and reliability of the pack.
 
_20250410152226
 
4. Battery Cell Stacking and Assembly - Stacking and Extrusion Technology 
The objective of power battery PACK stacking is to stack several battery cells or modules in a specific arrangement to achieve the desired voltage and capacity while optimizing the spatial arrangement. This ultimately contributes to enhancing the overall energy density while enabling structural stability and thermal management efficiencies of the battery pack, allowing compliance with performance and safety requirements for new energy vehicles.  
 
_20250410152302
 
5. Module Reinforcement and Locking - Module Wrapping with Steel Belt  
The ultimate goal of wrapping a power battery PACK with a steel belt is to augment the structural strength and stability of the module while safeguarding the battery cells from damage and prolonging the battery's lifetime. The steel belt can also assist in thermal management and maintain even battery temperature, while providing shielding against electromagnetic interference to facilitate the normal function of electronic equipment and offering heat-insulation and flame-retardant functions, thereby improving overall safety.  
 
_20250410152650
 
Note: The curing speed of the adhesive will slow down at lower temperatures during the production process. This means it could take longer for the adhesive to achieve the required strength profile. Therefore, a glue curing oven is needed to cure the glue, especially in low-temperature climates, prior to removal from the oven. 
 
ev battery pack testing
 
6. Interfacing with Pole Columns Positioning Cleaning - Pole Column Addressing and Laser Cleaning Process  
The key objective of Pole Column Addressing and Laser Cleaning is to assure welding quality with the goal of higher production efficiencies. Pole column addressing uses a vision system to precisely and accurately locate the position of the pole column so that welding can be achieved accurately. Once located, laser cleaning is administered to remove the oxide layer from the pole column, residual electrolyte, or contaminants from the surface, creating a better environment for welding. This results in higher levels of product quality and increased yield performance of the production line. The process of pole column addressing and laser cleaning will improve the welding strength of the modules while enhancing the overall performance of the battery module. Additionally, improving yield performance from the production line will reduce overall production costs of the Lithium-Ion Battery Pack Assembly Line, achieve environmentally friendly production results, and meet standards for "Green status."
 
_20250410152749
 
7. Connection System Assembly - Installation of the Cell Contact System 
The Cell Contact System (CCS) is installed to create an electrical connection between battery cells and the battery management system (BMS), facilitate adequate current transfer, and provide a structural fixing function, which maintains the stability of the battery cells in the PACK, and ensures safety and reliability during charging and discharging of battery cells. The major elements of the CCS typically include end busbars and contacts that act as combined electrical-mechanical interfaces in the battery PACK.
 
_20250410152901
 
8. Integrating the Weld System - Achieving Laser Welding  
The purpose of laser welding is to create a precise, efficient, and stable electrical connection between battery cells, the module, or internal connectors in the PACK. This welding method provides high-strength bonding assurance between layers and components, ensuring both structural integrity and electrical safety. It also offers better overall conductivity with lower resistance, which is crucial for performance. Due to the non-contact nature of this process, laser welding minimizes overheating and potential damage to external components while increasing production efficiency and quality.
9. Assessment of the Quality of Welding - Post Welding Cleaning and Inspection 
The purpose of post-welding cleaning and inspection is to confirm and assess that the quality of welding adheres to performance standards. This involves identifying possible defects in the welding points, such as false welding, cold welding, or burn-through points at the connection. It also includes removing any welding spatter, metal debris, or other contaminants that could affect performance, safety, and reliability. Additionally, post-welding cleaning and inspection prepares the surface for subsequent assembly and testing of the battery before PACK completion, ensuring the final product's performance and reliability.
10. Assessment of the Quality of Welding - Battery Testing System
The purpose of End of Line (EOL) comprehensive testing before the module is released from the production line is to utilize functional and performance measurements to review the performance and safety outputs of the battery module. This includes verifying that the battery module meets designed standards in electrochemical parameters, electrical connections, and thermal management elements. It also ensures that protection and containment functions are in place, and that the original design's safety aspects are met. By conducting EOL testing, potential issues can be identified early, reducing costs, rework, and maintenance downstream, and improving overall efficiencies in battery production productivity.
11. Integrated Assembly - Battery Pack Assembly Line  
After the completion of the module testing, the module can leave the Omni-Lab production line and go to the PACK assembly line.
 The assembly line also includes the following processes:  
• The Loading of Modules: Offload qualified battery modules to the PACK assembly line.  
• Component Preparation:Preassemble all components required for PACK, including BMS system, cooling system, shell, connectors, etc.
• Assembly: Use the automated or semi-automated assembly line to assemble battery modules and the other components into a full battery pack.  
• Electrical Connections: Configure all electrical connections correctly, meaning between modules and between module and BMS.  
• Sealing & Cooling System Integration: Ensure the battery pack is protected from external moisture and dust by sealing components and to incorporate any cooling systems needed to manage battery temperature.  
 
• Performance Testing:Create a testing regimen and carry out a series of performance tests, to determine voltage, internal resistance, insulation resistance, charging and discharging performance, etc.  
• Safety Testing: Create a testing regimen and carry out a series of safety tests, including overcharging, over-discharge, short circuit, temperature testing, etc., in order to verify the safety of the battery pack.  
• Data Logging:  Log all test data for quality-traceability testing and future analysis.  
 
• Final Inspection: Conduct a final visual and functional inspection to ensure that the appearance and function of the battery pack meet the requirements.
• Preparing for Shipping: Package the battery PACK, once the final inspection is passed, prepare for shipping.  
 
Share to: