Power battery is a key component in the "three-electric" system (motor, electronic control, battery) of new energy vehicles. It not only determines the vehicle's driving range but also directly affects the overall safety and performance. The manufacturing process of power batteries involves multiple steps, among which tightening and press-fitting processes are particularly important in battery assembly. The following sections will detail the manufacturing process of power batteries and their relationship with tightening and press-fitting processes, and explain why modern assembly processes increasingly require precision assembly products.
Relationship Between Power Battery Manufacturing Processes and Tightening/Press-FittingBasic Structure of Power BatteriesPower batteries typically consist of multiple cells (or battery units), modules, a Battery Management System (BMS), connectors, and a housing. Precision assembly of each component is crucial for the overall performance and safety of the battery.The cell is the core component of a power battery, typically using lithium-ion technology. Cell production involves steps such as coating, calendering, slitting, stacking or winding, electrolyte filling, and packaging. Press-fitting processes are widely used in these processes .During coating and calendering, anode and cathode materials are uniformly applied to current collectors and compacted via the calendering process. High-precision calendering equipment ensures uniform material thickness, improving the battery's energy density and consistency .For example, some battery manufacturers use high-precision calendering equipment, monitoring roll pressure and speed in real-time to control the thickness of each material layer within micrometer-level tolerances, thereby enhancing battery performance and consistency .During stacking or winding, anode and cathode sheets are layered or wound with separators in a specific sequence to form the cell core. This process requires precise press-fitting to ensure tight bonding between layers and prevent loosening or displacement .Some high-performance battery manufacturers use automated press-fitting equipment in the stacking process. Through precisely controlled pressure and displacement, they ensure consistency in the stacking process for each cell, reducing internal voids and inconsistencies .Battery modules consist of multiple cells connected via busbars and managed by the BMS. The tightening process plays a key role in ensuring the mechanical strength and electrical connection integrity of the module .Cells are secured within the module frame using the tightening process to ensure stability. Precise tightening torque prevents cells from loosening due to vibration or thermal expansion during operation .For instance, an electric vehicle manufacturer employs an intelligent tightening system in battery module assembly. Using torque sensors and data analysis, it ensures consistent tightening torque for each bolt, guaranteeing cell stability and safety .The Battery Management System (BMS) is a critical part of the battery module, monitoring and managing battery status. Its installation requires the tightening process to ensure secure attachment to the cells and connectors, guaranteeing reliable electrical connections .A battery module manufacturer uses automated tightening equipment during BMS installation. By monitoring and adjusting tightening torque in real-time, it ensures the electrical performance and mechanical strength of each connection point .The battery pack is composed of multiple battery modules assembled into a robust housing. Press-fitting and tightening processes are equally indispensable in this stage .Press-fitting of Battery ModulesBattery modules need to be precisely assembled into the battery pack housing. The press-fitting process plays a vital role in ensuring a tight fit between the modules and the housing. High-precision press-fitting equipment guarantees the accurate positioning of modules within the housing, avoiding performance degradation or safety issues caused by poor assembly .For example, an electric vehicle manufacturer uses high-precision hydraulic press-fitting equipment in battery pack assembly. Pressure and displacement sensors monitor the press-fitting process in real-time, ensuring the position and pressure for each module meet design requirements .The battery pack housing is secured using the tightening process to ensure mechanical strength and sealing. Precise tightening torque prevents housing deformation or loosening during use, thereby protecting the internal cells and modules .For instance, an electric vehicle manufacturer uses automated tightening equipment with torque control systems during battery pack housing assembly. By monitoring the torque and angle of each bolt in real-time, it ensures every connection point on the housing meets design requirements. This precise tightening process not only enhances the mechanical strength of the battery pack but also improves its waterproof and dustproof capabilities, ensuring reliability and safety under various conditions .Why Modern Assembly Processes Increasingly Require Precision Assembly ProductsImproving Product ReliabilityPrecision assembly significantly enhances product reliability by controlling the accuracy of every detail. In power battery manufacturing, precise press-fitting and tightening processes ensure the stability and consistency of cells, modules, and the battery pack, reducing failures and safety hazards caused by assembly errors .Enhancing Product PerformancePrecision assembly processes ensure the exact positioning and secure connection of each component, reducing internal resistance and energy loss, thereby improving battery efficiency and performance. For example, high-precision calendering and stacking processes can significantly increase the energy density and charge-discharge efficiency of cells .Power batteries experience various conditions during use, including vibration, impact, and thermal expansion. Precise tightening and press-fitting processes ensure battery components remain stable under these conditions, preventing safety issues like short circuits or leakage caused by loosening or displacement . For instance, in the assembly of battery modules and packs, precise tightening and press-fitting can effectively reduce friction and squeezing between cells, lowering the risk of thermal runaway .Meeting Stringent Quality StandardsWith the rapid development of the new energy vehicle market, quality standards for power batteries are becoming increasingly strict. Precision assembly processes, through high-precision control and monitoring, ensure each production step meets design and quality requirements . For example, intelligent tightening systems and high-precision press-fitting equipment can monitor and adjust assembly parameters in real-time, ensuring each product meets consistent high-quality standards .Automation and Intelligent ProductionModern power battery production relies heavily on automated and intelligent equipment. Precision assembly processes, integrated with advanced sensors and control systems, enable full automation and real-time monitoring of the production process . For instance, intelligent tightening systems and automated press-fitting equipment can adjust parameters in real-time during assembly, ensuring precision and consistency at each step, thereby improving production efficiency and product quality .The manufacturing process of power batteries is complex and precise, where tightening and press-fitting processes play a critical role in ensuring battery performance and safety. With the rapid development of the new energy vehicle market, demands for power battery performance, reliability, and safety are increasing, making precision assembly processes increasingly important. By introducing high-precision tightening and press-fitting equipment, along with intelligent control systems, manufacturers can significantly enhance the quality and consistency of power batteries, meeting market and user demands .
