Research on heat dissipation performance and flow characteristics of air-cooled battery pack

Abstract

Summary With the depletion of fossil fuels and the aggravation of environmental pollution, the research and development speed of electric vehicles has been accelerating, and the thermal management of battery pack has become increasingly important. This paper selects the electric vehicle battery pack with natural air cooling as the study subject, conducts simulation analysis of the heat dissipation performance of battery packs with and without vents. Then this paper researches on the influence of internal flow field and external flow field. Field synergy principle is used to analyze the effect of velocity field and temperature field amplitude. The results show the following: it is found that the maximum temperature rise and the internal maximum temperature difference of the battery pack with vents are reduced by about 23.1% and 19.9%, raising speed value can improve the heat dissipation performance, and raising temperature value can decrease the heat dissipation performance. Reasonable design of the vents can make the inner and outer flow field work synergistically to achieve the best cooling effect. Then the reference basis for the air cooling heat dissipation performance analysis of electric vehicle, battery pack structure arrangement, and air‐inlet and air‐outlet pattern choosing are offered.

Plate flat heat pipe and liquid-cooled coupled multistage heat dissipation system of Li-ion battery

“…Figure shows the temperature change of the 42 Ah Li‐ion cell at the discharge rate of 0.5 C. Table shows the thermodynamic parameter of the 42 Ah Li‐ion cell at different discharge rates. The below thermodynamic parameter showed that the cell's heating power increased significantly due to the increasing of discharge rates . The cell's heating power obtained by the experiment would be the basis of the simulation boundary condition in Section .…”

“…The below thermodynamic parameter showed that the cell's heating power increased significantly due to the increasing of discharge rates. 23,24 The cell's heating power obtained by the experiment would be the basis of the simulation boundary condition in Section 3.…”

Heat Dissipation Analysis on the Liquid Cooling System Coupled with a Flat Heat Pipe of a Lithium-Ion Battery

“… 5 This is because that the battery temperature will keep rising with the space constraint and time accumulation during charging and discharging processes. 6 − 8 When it exceeds the safety temperature range (−20 to 60 °C), 9 thermal runaway maybe caused and the consequence is fire accident. Actually, although the acceptable operating temperature range for Li-ion batteries is −20 to 60 °C, it is recommended to keep the temperature range within 15–35 °C to maintain optimal performance.…”

Novel investigation strategy for mini‐channel liquid‐cooled battery thermal management system

“…Currently, BTMS can be divided into air, liquid, phase change, and heat pipe cooling. Air cooling is widely used because of its simple structure and low cost, but its heat exchange capacity is limited .…”

“…9,10 Hence, temperature affects the working performance of the whole vehicle, making temperature a key factor that affects the performance of the battery. 11 Therefore, selecting a suitable battery thermal management system (BTMS) is needed to limit the operating temperature of lithium-ion batteries between 25 C and 40 C and ensure that the thermal gradient is within 5 C. [12][13][14][15] Currently, BTMS can be divided into air, 16,17 liquid, 18,19 phase change, 20,21 and heat pipe 22,23 cooling. Air cooling is widely used because of its simple structure and low cost, but its heat exchange capacity is limited.…”