Battery Thermal Management Systems (BTMS) for New Energy Vehicles (NEVs)
In the rapidly evolving landscape of the automotive industry, New Energy Vehicles (NEVs) are leading the charge towards a more sustainable future. At the heart of these vehicles lies the battery system, known as the battery pack, which is composed of hundreds of lithium-ion cells connected in series or parallel to meet the stringent voltage and power demands. However, the complex structure of the battery pack can lead to thermal gradients, as heat transfer between individual cells is often limited. This results in uneven temperature distribution within the battery, module, or pack, causing variations in charging and discharging behavior and electrochemical performance, which can further exacerbate temperature inconsistencies. The uniformity of lithium-ion batteries is crucial for the longevity and efficiency of the battery system, and maintaining consistent temperatures across all cells is a key challenge for Battery Thermal Management Systems (BTMS).
Battery Thermal Management Systems (BTMS)
To ensure widespread industrial adoption, batteries are designed with fixed shapes and geometries. In some applications, battery systems are subjected to extreme operating conditions such as high-rate charging and discharging, and exposure to high and low temperatures, which can increase the likelihood of system failure. To maintain optimal operating temperatures, a BTMS is essential. The choice of heat transfer medium significantly impacts the cost and performance of the BTMS. Common heat transfer media include air, liquids, and phase change materials (PCMs).
Air Cooling
Air cooling is generally considered an economical, effective, and reliable solution for BTMS in NEVs due to its simple structure, light weight, and ease of maintenance. Air cooling can be categorized into natural convection and forced convection. Natural convection relies on the spontaneous flow of air over the battery pack to dissipate heat. However, studies have shown that natural convection is insufficient for effective cooling in NEV BTMS. In contrast, forced convection offers superior heat exchange efficiency, as it involves the use of air pumps in conjunction with evaporators to circulate cooled or heated air effectively. With its proven performance, forced convection has been widely adopted in the automotive sector. Forced convection can be further divided into passive and active air convection systems.
Passive systems draw air from the atmosphere or the vehicle's cabin. The performance of these systems is highly dependent on ambient temperature. Active systems, on the other hand, utilize pre-conditioned air from the heating, ventilation, and air conditioning (HVAC) system's heater or evaporator. Generally, air that has been pre-treated by the heater or HVAC system demonstrates better thermal control capabilities under extreme conditions, such as low temperatures (below freezing) and high temperatures (above 45°C).
The duct structure of the BTMS also plays a significant role in its efficiency. The mainstream duct structures in NEVs can be divided into parallel and series ventilation systems. Comparative analysis of these two duct systems reveals that parallel ventilation BTMS provides lower maximum temperatures and more uniform temperature distribution than series ventilation BTMS. Considering the geometric dimensions of cylindrical cells, a novel axial flow air cooling system has been proposed. Axial ventilation can maximize the utilization of space within the battery pack, offering higher power density for NEVs equipped with cylindrical cells.
Our BTMS Solutions
At NEWBASE, we are at the forefront of innovation in battery thermal management. Our BTMS solutions are designed to address the unique challenges of NEVs, ensuring optimal performance and longevity of your battery systems. Our air cooling systems, in particular, offer:
- High Efficiency: Our forced convection systems provide superior heat exchange, maintaining consistent temperatures across all cells.
- Reliability: With simple and robust designs, our systems are built to last, requiring minimal maintenance.
- Adaptability: Our active air convection systems can adapt to a wide range of operating conditions, ensuring optimal performance in both extreme cold and heat.
- Space Optimization: Our novel axial flow designs maximize space utilization, enhancing the power density of your battery packs.
Contact Us
For more information on how our BTMS solutions can enhance the performance and safety of your NEVs, please contact us. Together, we can drive the future of sustainable transportation.
We look forward to partnering with you to revolutionize the way you manage battery temperatures in your NEVs.
