Heat dissipation analysis of double-layer battery pack under coupling heat transfer of air, liquid, and solid

Abstract

Summary Due to the sensitivity of the electrochemical performance of lithium‐ion batteries to temperature, the thermal management system becomes an essential component of pure electric vehicles. This paper selects a liquid‐cooled double‐layer battery pack for a certain car as the research object, determines the heating power of the battery cell through experiments, considers the existence of air domain in the battery pack to establish a battery pack thermal management system model, and analyzes the effects of different discharge rates, inlet flow rates, and inlet flow directions on the thermal performance of the double‐layer battery pack. The results show that the temperature of the upper module of the double‐layer battery pack is higher than that of the lower module at the same discharge rates and inlet flow rate; the maximum temperature of the upper module can be effectively reduced by increasing the liquid intake flow of the upper module. When the inlet flow rate of the upper module and the lower module is 550 and 500 L/hour respectively, the temperature distribution difference between the upper and lower modules of the double‐layer battery pack is the smallest, and the heat dissipation performance of the battery pack is the better. The conclusion can provide reference for structural design and optimization of thermal management system of the liquid‐cooled double‐layer battery pack.

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

“…The maximum temperature of the battery pack of the parallel liquid-cooling BTMS with different flow paths is 27.98 °C. 24 The maximum temperature of the battery pack of the flat heat pipe thermal management system is only 23.69 °C. This is because the excellent longitudinal heat transfer capability of the flat heat pipe thermal management system can transfer more heat.…”

“…Compared with the maximum temperature difference of 9.906 °C for the liquid-cooled double-layer BTMS, the temperature difference of the flat heat pipe thermal management system is only 2.08 °C. The maximum temperature of the battery pack of the parallel liquid-cooling BTMS with different flow paths is 27.98 °C . The maximum temperature of the battery pack of the flat heat pipe thermal management system is only 23.69 °C.…”

Numerical investigation on thermal performance of battery module with LCP‐AFC cooling system applied in electric vehicle

“…The hydraulic diameter D h and Reynolds number Re are expressed in Equation (18) and Equation (19), respectively,…”

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

“…The performance of the battery directly determines the development route of new energy vehicles. However, the internal electrochemical reaction of a lithium‐ion battery generates a large amount of heat, which causes the battery temperature and the reaction rate to increase . An increase in temperature causes an increase in the chemical reaction inside the battery, especially an internal harmful chemical reaction, which permanently damages the structure and reduces the working life of the battery .…”

“…However, the internal electrochemical reaction of a lithium-ion battery generates a large amount of heat, 6 which causes the battery temperature and the reaction rate to increase. 7,8 An increase in temperature causes an increase in the chemical reaction inside the battery, especially an internal harmful chemical reaction, which permanently damages the structure and reduces the working life of the battery. 9,10 Hence, temperature affects the working performance of the whole vehicle, making temperature a key factor that affects the performance of the battery.…”