3500mah 18650 battery.Heat pipe technology for thermal management of power batteries

　　As the energy density of power batteries continues to increase, the requirements for fast charging and the life requirements increase, there is an urgent need to develop new thermal management technology to solve the current technical bottleneck. Heat pipes, efficient thermal conductive elements, are the future high-performance power battery thermal components. The best choice for management systems.

　　Advantages of using heat pipes for battery thermal management

　　High heat dissipation efficiency

　　The heat pipe has extremely low thermal resistance (~0.1K·W-1) and extremely high thermal conductivity (>1000W·m-1K-1). Its heat dissipation heat flux density can reach more than 50W·cm-2, and its heat exchange capacity is far away. Higher than relying on forced air cooling or single-phase fluid convection heat transfer methods.

　　Fast heating rate

　　Public research data shows that when the battery is heated through heat pipe heat conduction, the heating rate is 1.5 times that of traditional PTC heating. With a heating power of 30W, the temperature can be raised by 20°C in 3 minutes. If the power is 70W, the temperature can be raised by 40°C in 2 minutes. Therefore, the starting time of electric vehicles in cold environments can be greatly shortened.

　　Good temperature equalization performance

　　Research shows that when a microchannel heat pipe with a length of 1m is heated at one end, the temperature difference along the length is less than 2°C; a 380cm2 flat plate heat pipe has a heat source with an area of 1cm2 and a heat output of 20W applied to the center of the entire surface. The temperature difference is also within 2°C, which reflects the excellent temperature uniformity of the heat pipe.

　　Good safety and high reliability

　　Battery packs that use heat pipes do not need to be circulated through water circuits to achieve separation of water and electricity, which is safer. In addition, the overall system structure is simple and easy to maintain, so the system reliability is higher.

　　Currently, many scholars and engineers in the thermal management industry are focusing on heat pipe technology and conducting a series of theoretical and experimental research. The existing research packages mainly involve: analysis of the impact of power battery heat generation characteristics on heat pipe heat transfer, research on heat pipe design methods for power batteries, research on heat dissipation structure design methods of thermal management systems, and research on low-temperature heating of batteries using heat pipes.

　　Existing research has verified the reliability and application value of heat pipes. However, as the requirements for thermal management systems in electric vehicles increase, the research on heat pipes still needs to be further in-depth:

　　Further combined with actual vehicle working conditions, an effective real-time control strategy for heat pipe heat dissipation is developed to achieve efficient and low-energy battery thermal management.

　　Fully consider the structural design and arrangement of heat pipes to optimize heat transfer performance, especially the performance analysis and structural design optimization of flat-plate heat pipes.

　　Based on the comprehensive system thermal and electrical characteristics as well as system energy consumption and lightweight indicators, a multi-objective optimization plan for the thermal management system is proposed.

　　Research on heating strategies in low-temperature environments needs further in-depth research.

Read recommendations:

AA

Lithium battery voltage rise and fall test

Battery pack nominal voltage and output voltage range

lithium 18650 li ion battery

lithium polymer battery 10000mah