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Summary: As lithium‐ion batteries (LIBs) are used in autonomous underwater vehicles (AUVs) power systems, their thermal safety and reliability have seriously inhibited the development of AUVs toward high speed and long voyage. However, the related research on AUVs' battery thermal management is very limited. In this article, a novel and efficient liquid cooling scheme is proposed, for battery thermal management of AUV, which adopts bionic wave cooling channels. A three‐dimensional heat dissipation model of the battery was developed, which considered the influence of battery internal resistance and state of charge on battery heat generation. The effects of discharge rate, channel shape, coolant mass flow rate, coolant inlet direction, and dynamic operation strategy on the battery maximum temperature and temperature variation were investigated during discharging process. It was found that the battery with bionic wave channels was superior to the battery with straight channels, regarding cooling efficiency. The maximum temperature and temperature difference of the former decreased by 12.8 and 5.3 K compared with the latter at 5C current discharging rate. Based on the bionic wave channels, increasing the mass flow rate of coolant was the most efficient route to reducing the maximum temperature and improving the uniformity of the battery temperature. A mass flow rate equal to 2.5 × 10−4 kg s−1 is reasonably recommended by considering the cooling efficiency comprehensively. The direction of the coolant inlet had little effect on the maximum temperature of the battery, but it significantly improved the uniformity of the battery temperature. Under the premise of meeting the cruising requirements of AUVs, alternating low‐rate and high‐rate discharge was more conducive to improving the temperature behavior of the battery. The conclusions of this article can provide reference for the battery thermal management system of AUVs. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]