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This study addresses the issue of heat dissipation in 18,650 cylindrical lithium-ion battery packs and proposes a novel heat dissipation model that combines paraffin wax-expanded graphite composite phase change material (CPCM) with liquid cooling. Initially, a comparison is conducted between the heat dissipation effects of the battery pack under natural convection and the heat dissipation achieved through the utilization of CPCM. Subsequently, the CPCM model is employed to identify the optimal battery arrangement. Subsequently, a heat dissipation model is developed by coupling CPCM with liquid cooling. The simulation outcomes obtained using COMSOL software demonstrate that employing the paraffin-expanded graphite CPCM liquid cooling coupled heat dissipation model can achieve a reduction in battery spacing to 0 mm while maintaining the maximum surface temperature of the battery between 20–45 °C and improving the temperature uniformity of the battery during 1–3 C cyclic charging and discharging. This approach ensures the battery pack’s normal operation, enhances safety, and prolongs the battery pack’s service life.

A large-capacity prismatic lithium-ion battery thermal management system (BTMS) combining composite phase change material (CPCM), a flat heat pipe (FHP), and liquid cooling is proposed. The three conventional configurations analyzed in this study are the BTMSs using only CPCM, CPCM with aluminum thermal diffusion plates, and CPCM with FHPs. In addition, a CPCM–FHP assisted with liquid cooling at the lateral sides is established to enhance the thermal performance of large-capacity batteries. Moreover, the influences of coolant temperature, the number of FHPs and cooling pipes, and the coolant direction on the temperature field of a BTMS are discussed. Finally, the orthogonal design method is used for the multi-level analysis of multiple factors to improve the light weight of the system. The optimal parameter combination is obtained to achieve the best thermal performance of the BTMS, with the maximum temperature and the temperature difference at 43.17 °C and 3.36 °C, respectively, under a maximum discharge rate of 2C and a high-temperature environment of 37 °C. The optimal scheme is further analyzed and affirmed through the comprehensive balance method.

In this study, a three-dimensional transient simulation model of a liquid cooling thermal management system with flow distributors and spiral channel cooling plates for pouch lithium-ion batteries has been developed. The cooling plates play the role of uniforming temperature distribution and reducing the maximum temperature within each battery, while the flow distributors have the function of reducing the temperature difference between batteries in the battery module. The accuracy of the thermophysical properties and heat generation rate of the battery was verified experimentally. The optimal structure and cooling strategy of the system was determined by single factor analysis as well as orthogonal test and matrix analysis methods. The optimal solution resulted in a maximum battery module temperature of 34.65 °C, a maximum temperature difference of 3.95 °C, and a channel pressure drop of 8.82 Pa. Using the world-harmonized light-duty vehicles test cycle (WLTC) conditions for a battery pack in an electric car, the performance of the optimal battery thermal management system (BTMS) design was tested, and the results indicate that the maximum temperature can be controlled below 25.51 °C and the maximum temperature difference below 0.21 °C, which well meet the requirements of BTMS designs.

Liquid cooling battery thermal management systems (BTMSs) are prevalently used in electric vehicles (EVs). With the use of fast charging and high-power cells, there is an increasing demand on thermal performance. In this context, a bionic fish scale (BFS) channel structure optimization design method is proposed to optimize the thermal performance. The effects of different structural parameters of the liquid cooling plate in BTMS on its cooling performance, including BFS notch diameter (D), BFS notch depth (H), and BFS notch spacing (S), are investigated. To minimize the maximum temperature (Tmax) and the maximum temperature difference (ΔTmax) as optimization indicators, experimental tests and numerical calculations are performed for a battery pack consisting of 36 square cells. Sixteen sets of thermal performance are discussed for different structural parameters in the transient thermal fluid simulation by using orthogonal tests. Under the optimal structural parameters, Tmax decreases by 1.61 °C (10.8%) and ΔTmax decreases by 0.43 °C (16.7%). In addition, the maximum increase in outlet flow velocity is 2.72% and the pressure is reduced by 4.98%. Therefore, the proposed BTMS will have effective cooling performance in high-power dissipation.

The battery thermal management system plays an important role in the safe operation of a lithium-ion battery system. In this paper, a novel liquid cooling plate with mini-channels is proposed and is improved with disturbance structures. First, an accurate battery heat generation model is established and verified by experiments. The error is less than 4%, indicating the heat generation power is reliable. Then, five designs are proposed first to determine the suitable number of disturbance structures, and plan 3 with five disturbance structures shows a satisfying performance in heat dissipation and flow field. Moreover, four layout plans are proposed, namely uniform, interlaced, thinning, and gradually denser distribution. Results show that plan 5 (uniform) achieves the best performance: the maximum average temperature is 36.33 °C and the maximum average temperature difference is 0.16 °C. At last, the orthogonal experiment and range analysis are adopted to optimize the structure parameters. Results show that the best combination is space between adjacent disturbance structures d1 = 20 mm, length d2 = 5 mm, width d3 = 1.5 mm, and tilt angle β = 60°.

The heat dissipation capability of the battery thermal management system (BTMS) is a prerequisite for the safe and normal work of the battery. Currently, many researchers have designed and studied the structure of BTMS to better control the battery temperature in a specific range and to obtain better temperature uniformity. This allows the battery to work safely and efficiently while extending its life. As a result, BTMS has been a hot topic of research. This work investigates the impact of pin-fins on the heat dissipation capability of the BTMS using the computational fluid dynamics (CFD) approach, designs several BTMS schemes with different pin-fin structures, simulates all schemes for fluid-structure interaction, and examines the impact of different distribution, number, and shape of pin-fins on heat dissipation capability and pressure drop. Analyzing the effect of cooling plates with different pin-fins on the thermal capability of the BTMS can provide a basis for the structural design of this BTMS with pin-fin cooling plates. The findings demonstrate that the distribution and quantity of pin-fin shapes might affect heat dissipation. The square-section pin-fins offer better heat dissipation than other pin-fin shapes. As the pin-fins number increases, the maximum battery temperature decreases, but the pressure drop increases. It has been observed that uniform pin-fin distribution has a superior heat dissipation effect than other pin-fin distribution schemes. In summary, the cooling plate with a uniform distribution of 3 × 6 square section pin-fins has better heat dissipation capability and less power consumption, with a maximum battery temperature of 306.19 K, an average temperature of 304.20 K, a temperature difference of 5.18 K, and a pressure drop of 99.29 Pa.

The purpose of this research is to develop effective methods for the thermal calculation of an electromagnetic mill. The article deals with the structural features of the liquid cooling system of such a device, with direct channel cooling of the induction coils. By analysing the recent research in this area, I have revealed that in order to achieve this goal it is expedient to use the finite element method (FEM). I have also suggested the input data for the boundary values to calculate a three-dimensional thermal field of an electromagnetic mill with an internal diameter of the working chamber of 200 mm. I have also graphically shown the results of calculating this problem using FEM analysis. Based on the analysis of the temperature field and gradient, I have also synthesized and substantiated the structure of the thermal equivalent circuit, which approximates the active part of the mill with a complex of five bodies with internal heat release and enables an approximate estimation of its thermal state at the initial stages of design to be held. I have suggested the formulae to calculate the parameters of this equivalent circuit and the principle to form a system of equations for the further determination of unknown temperatures. In addition, I have performed a comparative analysis of the methods for calculating the thermal state.

A battery thermal management system (BTMS) with functions of heat dissipation and heating by using only one liquid and one structure was studied, and a design for a new type of thermal management device structure was proposed. To find the influence factors of the BTMS on heat dissipation and heating characteristics, we selected and simulated three parameters: inlet size, liquid flow rate, and temperature. The convective heat transfer coefficient h and the Nusselt number Nu were used to analyze the influence of inlet size and liquid velocity on heat transfer intensity. The results show that: (1) In the temperature environment of 298 K with different discharge rates, a pipe diameter of 10 mm is the best size of the BTMS; (2) The increase in flow rate can increase the convective heat transfer coefficient h and the Nusselt number Nu. When the flow rate is 0.02 m/s, the growth rate of h and Nu is the largest; (3) The higher the fluid temperature, the faster the temperature of the battery pack increases in cold environments, but the uneven surface temperature of the battery is also more obvious.

In this article, a novel form of thermal interface material (TIM), represented by three industrially manufactured pressure-sensitive adhesive (PSA) tapes with electrical insulating properties, is characterized regarding its applicability in an electric motor with air-gap winding. Firstly, the adhesion performances, in terms of the winding process, were investigated experimentally. Here, every TIM shows sufficient shear strength for the wire–TIM joints, as well as peel adhesion to the laminated iron core. Secondly, the thermal–physical properties of the TIMs are inspected experimentally via laser flash analysis (LFA) and differential scanning calorimetry (DSC). For every TIM, the value of the thermal resistance can double if the relatively smooth surface (Ra = 0.2 μm) of the adjacent layers is interchanged with a rougher one (Ra = 2.0–3.7 μm). Additionally, the TIM’s performance at the system level is examined. Therefore, a flat test section, according to the specifications of the original motor, is studied experimentally and numerically utilizing infrared (IR) thermography and the finite element method (FEM). The focus is set on the heat flow and temperature distribution in the test section under varying thermal loads, mass flow, and variety of TIMs.

The cooling structure of a battery pack and coupled liquid cooling and phase change material (PCM) were designed in a thermal management system to enhance the cooling performance and extend the service life of lithium-ion battery packs. Numerical simulations were conducted based on the finite volume method. This study focuses on factors such as the layout of the terminal, flow rate of the coolant, different sections of the cooling pipe, position of the cooling pipe, and coupled liquid cooling, and investigates their influences on the operating temperature. The results show that a reasonable terminal layout can reduce heat generation inside the batteries. The appropriate flow rate and position of the cooling pipe effectively reduced the maximum temperature and minimized energy consumption. Then, the PCM was placed between the adjacent batteries near the outlet to enhance the uniformity of the battery pack. The temperature difference was reduced to near 5 K. This study provides a clear direction for improving the cooling performance and extending the service life of battery packs.

In order to ensure thermal safety and extended cycle life of Lithium-ion batteries (LIBs) used in electric vehicles (EVs), a typical thermal management scheme was proposed as a reference design for the power battery pack. Through the development of the model for theoretical analysis and numerical simulation combined with the thermal management test bench, the designed scheme could be evaluated. In particular, the three-dimensional transient thermal model was used as the type of model. The test result verified the accuracy and the rationality of the model, but it also showed that the reference design could not reach the qualified standard of thermal performance of the power battery pack. Based on the heat dissipation strategy of liquid cooling, a novel improved design solution was proposed. The results showed that the maximum temperature of the power battery pack dropped by 1 &deg, C, and the temperature difference was reduced by 2 &deg, C, which improved the thermal performance of the power battery pack and consequently provides guidance for the design of the battery thermal management system (BTMS).