The Battery Cooling Liquid Heat Exchanger Cold Plate is the core component of battery thermal management systems such as new energy vehicles and energy storage power stations. Its main function is to achieve precise temperature control, efficient heat dissipation/heating of battery packs through coolant circulation, ensuring battery safety, endurance, and service life. Its characteristics revolve around four core dimensions: heat transfer performance, structural adaptation, safety and reliability, durability and stability, as follows:
1、 Efficient heat transfer performance, precise temperature control
High thermal conductivity efficiency
High thermal conductivity materials such as aluminum alloy (6061/6063) and copper alloy are preferred for cold plate substrates. Some high-end products use aluminum copper composite structures with a thermal conductivity coefficient of 160-400 W/(m · K), which can quickly transfer the heat generated by the battery module to the coolant; At the same time, through microchannel design and turbulence structures such as fins, protrusions, and grooves, the contact area between the coolant and the inner wall of the cold plate is increased, enhancing the turbulent heat transfer effect. The heat transfer efficiency is improved by 30% -50% compared to traditional flat plate cold plates.
Excellent temperature uniformity
Adopting an integrated flow channel design (such as parallel flow channels, serpentine flow channels, and manifold flow channels) to ensure even distribution of coolant on the surface of the cold plate, the temperature difference between different areas of the battery module can be controlled within ± 2 ℃, avoiding the risk of battery capacity degradation and thermal runaway caused by local overheating; Supports bidirectional temperature control, and can be heated by coolant in winter to quickly reach the optimal working temperature (25-40 ℃) of the battery, solving the problem of reduced low-temperature endurance.
Low thermal resistance characteristic
The contact interface between the cold plate and the battery module is bonded with thermal conductive adhesive, thermal conductive gasket, or directly connected through vacuum brazing or friction stir welding, greatly reducing contact thermal resistance and minimizing heat transfer losses.
2、 Compact structure, suitable for battery pack integration requirements
Lightweight and slim design
In response to the demand for "reducing weight and increasing range" of new energy vehicles, the thickness of the cold plate can be controlled between 3-10mm, and the density of the aluminum alloy material is only 2.7g/cm ³, which reduces weight by more than 40% compared to traditional stainless steel cold plates; Simultaneously adopting an integrated structure, the cold plate can be integrated with the battery tray and liquid cooling pipeline design, reducing the number of components, saving internal space of the battery pack, and improving energy density.
Strong customization adaptability
The shape of the flow channel and installation interface can be customized according to the size and arrangement of different battery modules, such as square cells, cylindrical cells, and soft pack cells; Support multi-mode parallel/series connections to meet the heat exchange needs of different capacity battery packs; The surface of the cold plate can reserve positioning holes and welding slots, which are compatible with automated assembly processes and improve production line efficiency.
Reliable sealing performance
Vacuum brazing and helium testing processes are used for sealing treatment, with high welding strength and no risk of leakage. The sealing pressure of the coolant can reach 1.0-2.5MPa, meeting the sealing requirements under vehicle vibration and impact conditions, and avoiding the hidden danger of battery short circuit caused by coolant leakage.
3、 Safe and stable, meeting strict working conditions standards
Strong corrosion resistance
The surface of the cold plate is treated with processes such as anodizing, electrophoretic coating, and spray coating, which are resistant to coolant corrosion and salt spray corrosion (neutral salt spray testing can reach 500-1000 hours), and are suitable for complex working environments of the entire vehicle (such as high temperature, high humidity, acidic and alkaline environments); The coolant circuit can accommodate various heat exchange media such as ethylene glycol aqueous solution and silicone oil.
Excellent resistance to vibration and impact
The structural design complies with the vibration testing standards of the automotive industry (such as ISO 16750), and can withstand high-frequency vibrations, bumps, and impacts during vehicle operation. The connection between the cold plate and the pipeline is fixed with flexible joints and clamps to avoid fatigue fracture.
No electromagnetic interference
Using non-metallic thermal conductive media and non-magnetic metal materials, it will not cause electromagnetic interference to the signal transmission of the battery management system (BMS), ensuring precise monitoring and control of the temperature control system.
4、 Durable and adaptable to long-term usage needs
long service life
The design service life of the cold plate can reach 8-15 years (matching the service life of the power battery), and the anti fatigue performance of the brazed structure is excellent. After thousands of cold and hot cycle tests (-40 ℃~85 ℃), there are still no problems such as deformation, leakage, or performance degradation.
Low maintenance cost
The integrated sealing structure does not require regular disassembly and maintenance, only impurities need to be filtered through the cooling liquid filtration device of the thermal management system, reducing later operation and maintenance costs; Some products support modular replacement, and a single cold plate failure does not affect the overall operation of the battery pack.
5、 Typical application scenarios and additional advantages
Core application areas: New energy passenger/commercial vehicle battery packs, energy storage power station container battery modules, portable energy storage power sources, drone batteries, etc.
Energy saving and consumption reducing advantages: Compared with air-cooled systems, liquid cooled plates have higher heat transfer efficiency, reduce temperature control power consumption by 20% -30%, and help improve the range of new energy vehicles.
Strong compliance: Complies with safety and performance testing standards for power batteries such as ISO 12405 and GB/T 31467, passes thermal runaway protection testing, and meets the entry requirements of vehicle manufacturers.
