Structural Design and Packing Technology Optimization of Power Battery Systems

I. Structural Design of Power Battery Systems

The structure of a power battery system comprises cells, modules, and battery packs. The cell is the most fundamental unit, and its structural design and material selection are decisive for battery performance. Mainstream cell types currently available include cylindrical, prismatic, and pouch cells, each offering certain advantages in terms of energy density, safety, and cost. For instance, cylindrical cells exhibit high energy density and low cost but relatively poor safety; prismatic cells strike a balance between safety and cost; pouch cells, which emerged early and are widely used in 3C applications, are gaining momentum in power applications and hold significant development potential. A module typically consists of a certain number of cells connected in series and/or parallel, equipped with a thermal management system and electrical connections. Module design aims to protect cells from external environmental influences and enhance the overall performance of the battery system. Key considerations during module design include thermal and electrical isolation between cells to ensure safety and stability. Companies like XIAMEN TOB NEW ENERGY TECHNOLOGY CO., LTD. specialize in delivering tailored battery module and pack production solutions, ensuring optimal performance and reliability from the module level up. The battery pack represents the final form of the power battery system, featuring a complex structure generally composed of battery modules, a thermal management system, a battery management system (BMS), an electrical system, and structural components. The structural parts of the battery pack, such as the upper cover, enclosure, and lower cover, provide safe isolation and protect the cells from external impacts. The electrical system, primarily consisting of a high-voltage control box and high-voltage interfaces, is responsible for power transmission and distribution. During battery pack structural design, safety performance must be thoroughly considered. For example, multi-layer structures and thermal isolation technologies can reduce heat generation during operation, while smart sensors and algorithms enable real-time monitoring of battery status to prevent abnormalities such as overcharging or over-discharging.

II. Power Battery Packing Technology

As a critical technology in the field of new energy vehicles, power battery packing directly impacts the energy density, safety, and reliability of the battery system. With the rapid development of the new energy vehicle market, power battery packing technology has undergone continuous innovation and improvement. Power battery packing primarily involves three configurations: series, parallel, and hybrid connections. Series connections meet high-voltage requirements, making them suitable for high-voltage output scenarios. Parallel connections increase the system’s capacity and driving range. Hybrid configurations combine the advantages of both, simultaneously accommodating high-voltage and high-capacity demands.

In practice, power battery packing must consider multiple factors. First, inconsistencies among cells pose a significant challenge. Due to variations in manufacturing processes and materials, cells may differ in performance. Thus, measures such as optimized cell selection and pairing, along with advanced BMS, are essential to minimize inconsistencies and improve overall battery performance.

TOB NEW ENERGY offers comprehensive battery pilot line and battery lab line solutions to help clients test and address these challenges, ensuring seamless scaling from lab to production with consistent cell quality. Second, thermal management is a critical aspect of power battery packing, encompassing cooling and heating management. During operation, batteries generate substantial heat, which, if not dissipated effectively, can lead to temperature rise, compromising performance and safety. Cooling management techniques, including air cooling, liquid cooling, heat pipe cooling, and phase change cooling, ensure the battery operates within an optimal temperature range. In low-temperature environments, lithium-ion batteries experience increased internal resistance and reduced capacity. Extreme conditions may even cause electrolyte freezing and inability to discharge, significantly impacting the low-temperature performance of the battery system and leading to reduced power output and driving range in electric vehicles. Therefore, charging under low-temperature conditions typically involves pre-heating the battery to a suitable temperature. Heating management techniques include internal and external methods. External heating, which employs high-temperature gases, liquids, electric heating plates, phase change materials, or the Peltier effect, is relatively safer. Internal heating utilizes Joule heat generated during battery operation but has unclear impacts on battery lifespan and safety, with limited application in electric vehicles.

Finally, power battery packing must prioritize safety. Measures such as overcharge protection, over-discharge protection, and temperature protection are necessary to prevent abnormalities. Additionally, battery systems must undergo rigorous testing and validation to ensure compliance with relevant safety standards and requirements. This is a core part of TOB NEW ENERGY's integrated equipment and commissioning services.

III. Optimization Strategies for Structural Design and Packing Technology

1. Innovation in Material Technology

For new energy vehicle power batteries, advancements in material science and technology are key to improving performance. Progress in material science plays a crucial role in optimizing battery structure and packing technology. First, cathode material research is a critical breakthrough point for enhancing battery performance. For example, high-nickel ternary materials significantly increase energy density, thereby extending the driving range of new energy vehicles. Additionally, modification techniques such as doping and coating further improve the stability and safety of cathode materials. Second, innovation in anode materials is an important direction for power battery development. Silicon-based anode materials, with their high specific capacity and suitable lithium intercalation potential, are the preferred choice for next-generation lithium-ion battery anodes. Nanoscale and composite approaches address the volume expansion issue of silicon anodes during charging and discharging, effectively extending battery cycle life. However, compared to carbon, silicon materials are relatively expensive, and large-scale production must consider cost. Selecting appropriate silicon sources and employing correct nanoscale processes can mitigate application challenges and promote the commercial production of silicon-based anode materials.

TOB NEW ENERGY provides cutting-edge battery materials and technical support for both cathode and anode innovation, facilitating such R&D and commercialization efforts. Third, the characteristics of electrolytes and separators significantly impact overall battery performance. Developing new electrolytes can reduce internal resistance and improve energy conversion efficiency, while high-performance separators effectively prevent internal short circuits and self-discharge.

2. Optimization of Module Design and Manufacturing Processes

Module design is central to power battery packing technology, and its rationality and advancedness directly affect the overall performance of the battery system. Continuous innovation and improvement in module design and manufacturing processes are essential for enhancing power battery performance. First, module design optimization involves structural layout and cell arrangement. Rational structural layouts reduce internal resistance and thermal resistance, improving energy transfer efficiency. Scientific cell arrangements ensure good shock resistance under external impact. Second, advancements in manufacturing processes are crucial for module optimization. Advanced welding, encapsulation, and testing technologies ensure stability and consistency during production. For example, laser welding enables precise connections between cells and modules while reducing contact resistance, and automated encapsulation lines increase production efficiency and reduce human error. TOB NEW ENERGY offers customized battery equipment and end-to-end battery production line solutions to achieve these precise manufacturing goals. Finally, module design and manufacturing process improvements must fully consider heat dissipation characteristics. Optimizing heat dissipation structures and using efficient thermal materials effectively reduce heat generation during operation and enhance the thermal stability of the battery system.

3. Integrated Optimization of Thermal and Energy Management

Integrated optimization of thermal and energy management in new energy vehicle power battery systems is key to improving performance and safety. As battery technology evolves, higher demands are placed on thermal and energy management. The focus of thermal management is efficiently dissipating heat generated during battery operation to prevent overheating. Integrated optimization strategies include using advanced thermal conductive materials, designing rational heat dissipation structures, and incorporating intelligent temperature control systems. Compared to air cooling, liquid cooling with cooling plates is more efficient, and aluminum or aluminum alloy cooling plates are relatively low-cost. Key research directions involve optimizing the structure and fluid dynamics of cooling plates to simplify manufacturing and enhance effectiveness. Recent studies focus on coolant channel design, reducing flow resistance and improving temperature uniformity. For example, some experts have designed a new liquid cooling plate based on serpentine channels, significantly improving cooling efficiency under specific conditions. Tesla’s 4680 CTC battery pack uses a serpentine design for its internal cooling plate. Others have designed honeycomb-structured cooling plates for prismatic batteries, enhancing heat dissipation by increasing cooling channels. Phase change material (PCM)-based heat dissipation systems are passive thermal management systems that use latent heat storage and release to maintain the battery pack at an optimal temperature. They offer advantages such as no energy consumption, no moving parts, and low maintenance costs. However, PCMs have relatively low thermal conductivity, so embedding metal materials into PCMs can mitigate this inherent drawback. In energy management, the focus is on the rational distribution and efficient utilization of battery energy. Accurate energy management strategies can extend driving range, improve energy conversion efficiency, and reduce energy loss. Integrated optimization includes optimizing charging algorithms, incorporating energy recovery systems, and using intelligent energy scheduling strategies. For example, some new energy vehicles employ smart charging technology that adjusts charging current and voltage based on real-time battery status and user habits to utilize battery energy effectively. Integrated optimization of thermal and energy management must also consider their synergy. Rational integration allows thermal and energy management to complement and promote each other. For instance, when battery temperature is too high, the energy management system can automatically adjust operation to reduce heat generation, while the thermal management system dissipates heat promptly to prevent damage.

IV. Development Directions for Structural Design and Packing Technology

1. High Energy Density and Long Lifespan

Against the backdrop of rapid development in the new energy vehicle market, the energy density and lifespan of power batteries have become focal points of research.

The structure and packing technology of power batteries are evolving toward higher energy density and longer lifespan. Increasing energy density is crucial for extending the driving range of new energy vehicles. Researchers are developing new cathode and anode materials with higher energy density and better performance stability, such as high-nickel ternary materials and silicon-carbon composites. Optimizing battery structure is another important approach, such as using multi-layer structures and thinner separators to further improve energy density. Recent research on rational design and innovative preparation of nickel-rich single-crystal ternary cathode materials for lithium-ion batteries has yielded new results. Compared to polycrystalline structures, single-crystal nickel-rich ternary cathode materials offer outstanding advantages in compaction density and safety performance, making them the preferred choice for next-generation all-solid-state battery cathodes. For example, based on the Ostwald ripening law, researchers established a relationship between temperature, particle size, and calcination time and developed a high-temperature short-time pulsed lithiation technique to precisely control the size of high-quality single crystals. They successfully synthesized NCM83 single-crystal particles with a size of 3.7 μm, exhibiting more uniform stress distribution. After 1,000 cycles in a pouch full cell, the capacity retention rate reached 88.1%.This work provides important theoretical guidance and technical support for designing and synthesizing high-specific-energy single-crystal nickel-rich ternary cathode materials with excellent cycle stability.

Long lifespan is essential for the sustainable development of power batteries. Researchers are working to increase cycle times and reduce decay rates. This can be effectively achieved by improving manufacturing processes, optimizing BMS, and adopting advanced thermal management technologies. TOB NEW ENERGY supports these efforts through its comprehensive battery production line solutions and R&D support services.

2. Enhanced Safety and Reliability

Safety and reliability are perpetual themes in the development of power battery structure and packing technology. Future advancements will place greater emphasis on these aspects. In material selection, researchers will focus more on thermal and chemical stability to reduce risks of thermal runaway and short circuits during operation. Using thermally stable cathode materials and flame-retardant electrolytes can significantly improve battery safety. In battery structure, optimized cell design and module layout reduce internal stress concentration and potential safety hazards. Introducing multiple safety protection mechanisms, such as thermal isolation, overcharge protection, and over-discharge protection, can promptly cut off power in case of abnormalities, preventing accidents. From a manufacturing perspective, stricter quality control standards and advanced production equipment ensure battery consistency and reliability. Refined manufacturing processes reduce defects and failure rates, improving overall battery performance.

With the rapid development of the Internet of Things (IoT), big data, and artificial intelligence (AI), power battery structure and packing technology are becoming increasingly intelligent and integrated. In the future, power battery systems will become smarter and more efficient, providing strong support for enhancing the performance of new energy vehicles and optimizing user experience. Intelligence is a major development direction for power battery systems. Incorporating smart components such as sensors, actuators, and controllers enables real-time monitoring and precise control of battery status. Real-time monitoring of temperature, voltage, and current allows timely detection and handling of abnormalities. Precise control of charging and discharging processes optimizes energy utilization efficiency and extends battery lifespan. Integration is another important method for optimizing power battery systems. Integrated design of multiple functional modules and components reduces system complexity and improves overall performance. Integrating BMS, thermal management systems, and energy recovery systems enables unified control and optimized management. Using highly integrated battery modules and lightweight materials further reduces system weight and size, increasing the energy efficiency ratio and driving range of new energy vehicles.

V. Conclusion

This article provides an in-depth analysis of optimization measures for the structural design and packing technology of new energy vehicle power battery systems, covering material technology, safety, reliability, intelligence, and integration. It reveals key factors for performance improvement and development directions. Against the backdrop of rapid market development and technological progress, the structural design and technology of power battery systems will continue to be optimized and innovated, providing strong support for the widespread application and sustainable development of new energy vehicles. XIAMEN TOB NEW ENERGY TECHNOLOGY CO., LTD. is committed to supporting this evolution through its comprehensive suite of battery production and research solutions, from custom equipment and material supply to full production line delivery and technical support.