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Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, the synthesis of a novel microencapsulated phase change material via a sol–gel method is presented, featuring disodium hydrogen phosphate dodecahydrate as the core and a SiO2/graphene oxide composite as the shell. The morphology and core–shell microstructure of the synthesized microcapsules are characterized using scanning electron microscopy. The phase change performance and thermal stability are evaluated by differential scanning calorimetry and a high/low temperature test chamber, respectively. Energy dispersive X‐ray spectroscopy and Fourier transform infrared spectroscopy are employed to determine the chemical composition of the microcapsules. The findings reveal that the MEPCM exhibited a high melting enthalpy of 174.3 J g−1. The degree of supercooling is reduced by 2.1 °C, and after 600 thermal cycles, the phase change enthalpy of the microcapsules showed a minor decrease of ≈6.0%. Notably, the thermal conductivity of the microcapsules is significantly enhanced, increasing by up to 51.8%. When integrated into the thermal management systems of lithium‐ion batteries, the MEPCM effectively maintained the battery temperature below 46 °C under a 3 C charging rate. In summary, these results suggest that the hydrated salt microcapsule with its hybrid silica and graphene oxide shell is a promising material for the thermal management of lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are fundamental to modern electric vehicles, offering high energy density, long cycle life, and low self-discharge rates. However, thermal runaway--a critical safety issue involving uncontrolled temperature increases--can lead to fire or explosion. Ensuring flame retardancy is crucial in accidents where battery packs are exposed to external fires. Additionally, battery packs are susceptible to mechanical stresses and potential damage from ground impacts like debris or uneven road surfaces. Effective thermal management significantly impacts capacity and longevity. This review emphasizes the importance of researching flame retardancy, ground impact resistance, and thermal management, especially in composite battery enclosures. Composites serve as a lightweight alternative to metals and help overcome one of the main constraints of EVs, which is weight. Ground impact refers to the physical force battery packs endure during collisions, hitting potholes, debris, or accidents. Therefore, understanding the effects of ground impact on battery enclosures is crucial for design considerations. Effective thermal management is also essential, as it directly affects the performance and safety of Lithium-ion battery packs in EVs. [ABSTRACT FROM AUTHOR]

This study presents a bionic structure-based liquid cooling plate designed to address the heat generation characteristics of prismatic lithium-ion batteries. The size of the lithium-ion battery is 148 mm × 26 mm × 97 mm, the positive pole size is 20 mm × 20 mm × 3 mm, and the negative pole size is 22 mm × 20 mm × 3 mm. Experimental testing of the Li-ion battery's heat generation model parameters, in conjunction with bionic structure and micro-channel features, has led to the development of this innovative cooling system. The traditional bionic liquid cooling plate's structure is often singular; however, the flow path of the liquid cooling plate designed in this paper is based on the combination of the distribution of human blood vessel branches and the structure of insect wing veins. The external dimension of the liquid cooling plate is 152 mm × 100 mm × 6 mm (length × width × height). Utilizing numerical simulation and thermodynamic principles, we analyzed the heat transfer efficacy of the bionic liquid cooling module for power batteries. Specifically, we investigated the impact of varying coolant flow rates and the contact radius between flow channels on the thermal performance of the bionic battery modules. Our findings indicate that a liquid flow rate of 0.6 m/s achieves a stable maximum surface temperature and temperature differential across the bionic battery liquid cooling module, with a relatively low overall system power consumption, suggesting room for further enhancement of heat transfer performance. By augmenting the contact radius between flow channels, we observed an initial increase in the maximum surface temperature, temperature differential, and inlet–outlet pressure differential at a flow rate of 0.2 m/s. However, at flow rates equal to or exceeding 0.4 m/s, these parameters stabilized across different design Scenarios. Notably, the pump power consumption remained consistent across various scenarios and flow rates. This study's outcomes offer valuable insights for the development of liquid-cooled battery thermal management systems that are energy-efficient and offer superior heat transfer capabilities. [ABSTRACT FROM AUTHOR]

This paper reports on a novel hybrid thermal management strategy. It uses secondary coolants (air and liquid) to withdraw heat simultaneously from the composite phase change material, resulting in increased heat extraction capability of the composite phase change material and improved thermal environment of the battery module. The significance of this strategy is that the fluid used in the liquid cooling stays stationary. Comprehensive experimental and numerical studies are performed, and parametric studies are conducted to reduce the volume of the phase change material, size of the air duct, and airflow Reynolds number. The numerical results showed that the maximum temperature was limited to 27.8°C, and a high‐temperature uniformity of 0.4°C was obtained. Furthermore, the required volume of the composite phase change material is reduced by ~50%. Additionally, beyond a 6 mm height of the air duct, the reduction in maximum pressure drop is not significant enough, and it is considered the optimal height, and a Reynolds number of 1950 is considered the optimal airflow Reynolds number. Therefore, the proposed thermal management concept for the battery module can sustain the thermal environment needed for the effective operation of Lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are alternatives to traditional combustion engine-powered vehicles. This work focuses on a thermal management system for battery EVs using liquid cooling and a machine learning (ML) model to predict their thermal-related health. Real-world data of EV operation, battery and cooling conditions were collected. Key influencing factors on the thermal-related health of batteries were identified. The ML model's effectiveness was evaluated against experimental test data. The ML model proved effective in predicting and analyzing battery thermal health, suggesting its potential for use with the thermal management system. [ABSTRACT FROM AUTHOR]

The thermal performance of a lithium-ion battery pack for an electric vehicle by adding straight rib turbulators in battery cooling plate channels has been numerically investigated in this paper and the numerical model of the battery pack has been validated by experimental data, which exhibits a satisfactory prediction accuracy. The effects of rib shapes, rib angles, rib spacings, and irregular gradient rib arrangement configurations on the flow and heat transfer behaviors of battery pack cooling plates have been thoroughly explored and analyzed in this paper. In addition, the thermal performance of the ribbed battery cooling plates was examined at actual high-speed climbing and low-temperature heating operating conditions. The results indicate that compared to the original smooth cooling plate, the square-ribbed battery cooling plate with a 60° angle and 5 mm spacing reduced the maximum battery temperature by 0.3 °C, but increased the cross-sectional temperature difference by 0.357 °C. To address this issue, a gradient rib arrangement was proposed, which slightly reduced the maximum battery temperature and lowered the cross-sectional temperature difference by 0.445 °C, significantly improving temperature uniformity. The thermal performance of the battery thermal management system with this gradient rib configuration meets the requirements for typical electric vehicle operating conditions, such as high-speed climbing and low-temperature heating conditions. [ABSTRACT FROM AUTHOR]

In the current era of energy conservation and emission reduction, the development of electric and other new energy vehicles is booming. With their various attributes, lithium batteries have become the ideal power source for new energy vehicles. However, lithium-ion batteries are highly sensitive to temperature changes. Excessive temperatures, either high or low, can lead to abnormal operation of the batteries, posing a threat to the safety of the entire vehicle. Therefore, developing a reliable and efficient Battery Thermal Management System (BTMS) that can monitor battery status and prevent thermal runaway is becoming increasingly important. In recent years, deep learning has gradually become widely applied in various fields as an efficient method, and it has also been applied to some extent in the development of BTMS. In this work, we discuss the basic principles of deep learning and related optimization principles and elaborate on the algorithmic principles, frameworks, and applications of various advanced deep learning methods in BTMS. We also discuss several emerging deep learning algorithms proposed in recent years, their principles, and their feasibility in BTMS applications. Finally, we discuss the obstacles faced by various deep learning algorithms in the development of BTMS and potential directions for development, proposing some ideas for progress. This paper aims to analyze the advanced deep learning technologies commonly used in BTMS and some emerging deep learning technologies and provide new insights into the current combination of deep learning technology in new energy trams to assist the development of BTMS. [ABSTRACT FROM AUTHOR]

To reduce the battery performance attenuation of electric vehicles under high and low temperature conditions, it is necessary to design a battery thermal management system to avoid unnecessary energy consumption, while improving safety and endurance. In this paper, a battery thermal management system is established. Considering the time-delay and nonlinear characteristics of the battery system itself, the control strategy is designed based on multivariate model predictive control (MPC), and the simulation is carried out based on MATLAB. Simulation results show that MPC controller can save energy and improve efficiency, and have a better control effect than PID control. [ABSTRACT FROM AUTHOR]

The power battery is a key component of electric vehicles and its performance is greatly affected by temperature. Battery thermal management systems based on phase change materials can effectively control the battery temperature and at the same time have the advantages of simple structures, energy savings, and good temperature uniformity, and has broad development prospects. In this paper, expanded graphite–paraffin composite phase change materials were prepared, phase change material cooling experiments were carried out, and a phase change material cooling simulation model was also established using the Fluent software to study the influence of phase change material thermophysical parameters on thermal management performance. The results show that the phase change material thermal management method has excellent cooling performance. The best thermal management performance is achieved at the 3C discharge rate, with a phase change material filling thickness of 4 mm, a melting point of 40 °C above ambient temperature, and a thermal conductivity of 3 W/(m·K). When the phase change latent heat was increased from 150 J/g to 250 J/g, the liquid phase ratio decreased from 0.84 to 0.51, and the subsequent cooling performance was greatly improved, so the phase change latent heat should be increased as much as possible. [ABSTRACT FROM AUTHOR]

Electric mobility decarbonizes the transportation sector and effectively addresses sustainable development goals. A good battery thermal management system (BTMS) is essential for the safe working of electric vehicles with lithium‐ion batteries (LIBs) to address thermal runaway and associated catastrophic hazards effectively. However, PCMs suffer from low thermal conductivity issues, and hence, enhancement techniques include the use of fins, nano‐additives, extended graphite powder, and so forth. The use of composite phase change materials effectively addresses LIB thermal management widely used in electric vehicles while mitigating thermal runaway, besides providing flame retardancy, thermal/mechanical stability, and electrical insulation, and preventing leakage. It is noted that no single strategy of BTMS is brought down to a safe zone of temperature, and hybrid BTMSs are being employed, invariably involve phase change materials (PCMs) to a large extent. It is essential to utilize CPCMs to address the effects of low‐temperature environments and vibrations considering vehicle driving cycles and operating conditions. It is observed from the review that ultrasonic monitoring and early detection of internal short circuits are the steps towards mitigation of thermal runaway propagation. It is required to utilize optimization methods, machine learning and IoT tools for a feasible PCM based BTMS work. Present review briefly describes potential methods for effective utilization of PCMs, comparison among different methods, challenges associated and potential solutions. It is highly essential to develop compact and economical BTMS with effective CPCMs for better and safer LIB operation to attract large‐scale commercialization of electric vehicles. [ABSTRACT FROM AUTHOR]

Lithium battery temperatures will increase if the heat produced during the charging and discharging procedures is not promptly vented externally. Fewer investigations have been conducted on materials that can retain good flexibility at room temperature and shape stability at high temperatures under the existing thermal management system for phase change materials (PCM). In this study, a particular kind of flexible composite PCM (CPCM) at room temperature is created to address the issue of heat transfer between the PCM and the power battery. The characteristics of hardness, room-temperature flexibility, form stability at high temperature, and thermal conductivity are compared with those of three other thermally induced flexible CPCMs. The flexibility at room temperature of the new CPCM is demonstrated by the results, which makes assembly easier and helps further lower the contact thermal resistance. Charge–discharge test comparisons of the battery modules employing the chosen CPCM and thermally induced CPCM are performed to further evaluate their thermal management capabilities. The thermally induced CPCM exhibits larger maximum temperature profiles at the discharge rates of 1C, 2C, and 3C than the room-temperature flexible CPCM. The variations in maximum temperatures are 0.96, 1.48, and 2.08 °C. [ABSTRACT FROM AUTHOR]

Battery design efforts often prioritize enhancing the energy density of the active materials and their utilization. However, optimizing thermal management systems at both the cell and pack levels is also key to achieving mission-relevant battery design. Battery thermal management systems, responsible for managing the thermal profile of battery cells, are crucial for balancing the trade-offs between battery performance and lifetime. Designing such systems requires accounting for the multitude of heat sources within battery cells and packs. This paper provides a summary of heat generation characterizations observed in several commercial Li-ion battery cells using isothermal battery calorimetry. The primary focus is on assessing the impact of temperatures, C-rates, and formation cycles. Moreover, a module-level characterization demonstrated the significant additional heat generated by module interconnects. Characterizing heat signatures at each level helps inform manufacturing at the design, production, and characterization phases that might otherwise go unaccounted for at the full pack level. Further testing of a 5 kWh battery pack revealed that a considerable temperature non-uniformity may arise due to inefficient cooling arrangements. To mitigate this type of challenge, a combined thermal characterization and multi-domain modeling approach is proposed, offering a solution without the need for constructing a costly module prototype. [ABSTRACT FROM AUTHOR]

In order to improve the energy efficiency of pure electric vehicles, the author proposes a thermal energy recovery and automation monitoring system for motor equipment based on new energy vehicles. Based on the analysis of the battery thermal management model, a series heat exchange model between the motor and the battery was established. An integrated thermal management system control strategy based on motor waste heat recovery was proposed for electric vehicles in low temperature environments, and simulation and validation were conducted at different environmental temperatures (-10~0 °C). The simulation results show that this configuration can shorten the heating time by 111-343 seconds compared to traditional battery thermal management systems during the heating stage. During the insulation stage, frequent activation of positive temperature coefficient thermistor can be avoided and the battery temperature can be maintained around 20 °C, which is not only conducive to extending the battery life but also reduces the comprehensive energy consumption by 4.39-7.70%. On the other hand, this configuration can reduce the impact of low temperature on comprehensive energy consumption from 9.77-2.07%. It is proved that heat recovery can effectively alleviate the range anxiety caused by ambient temperature. [ABSTRACT FROM AUTHOR]

In this study, a comprehensive simulation study was carried out to obtain detailed battery temperature behaviors. The influences of air inlet temperature, air flow rate, C‐rate, and free stream temperature were investigated on the temperature uniformity and maximal battery temperature. Taguchi design is implemented to investigate the main effects of four control parameters in the battery thermal management process. Results indicated that as the free stream temperature (delta = 7.3366) was the most influential factor for the temperature uniformity, the air inlet temperature (delta = 0.2679) was the most efficient factor for the maximal battery temperature. The contribution of the air inlet temperature was 28% and 38% for temperature uniformity and maximal battery temperature, respectively. Additionally, the free stream temperature contributed 32% to temperature uniformity and 25% to the maximum battery temperature. The airflow rate was found to be the least effective factor for temperature uniformity (delta = 2.8672) and maximal battery temperature (delta = 0.0506). The results could be helpful in the design of a lithium‐ion battery thermal management process to improve temperature uniformity and maximal battery temperature. [ABSTRACT FROM AUTHOR]

Liquid‐cooling techniques are commonly employed for battery thermal management (BTM) in commercial vehicles and energy storage applications, typically incorporating a cooling plate positioned beneath the casing of the battery pack. However, this heat transfer structural design results in smaller temperature drop in the terminal batteries located distantly from the plate, leading to an increased temperature difference. The integration of supplementary media into BTM systems holds the potential to enhance thermal management performance, thereby offering a viable solution to this issue. Herein, a fan is incorporated into the liquid‐cooling system to induce air circulation and augment convective heat transfer onto the battery surface. In the findings, it is revealed that the implementation of a reverse airflow path beneath the cooling plate result in a temperature decreasing rate of 0.59 K min−1, indicating a notable enhancement of 23% compared to solely employing a liquid‐cooling configuration. In the results, it is demonstrated that 1) reducing the inlet temperature can effectively enhance the rate of temperature reduction and 2) increasing the fan speed can reduce the temperature difference and promote temperature uniformity. In conclusion, in this present study, comprehensive guidelines and references are provided for the future design of BTM. [ABSTRACT FROM AUTHOR]

Thermal management is a crucial design aspect for the safety and performance of the Lithium-ion battery pack used in electric vehicles. Phase change material (PCM) based battery thermal management is one of the appropriate passive or hybrid thermal management. The present paper highlights the selection of PCM depends on various factors related to application operating conditions like ambient temperature, the heat released by the battery, and the type of battery pack design. In selecting PCM, a thorough understanding of various PCMs requires an overall review of multiple types and properties of organic and inorganic PCM, using phase change equilibrium diagrams to comprehend phase change transformations. Further, the present work summarizes the various studies on PCM durability, different thermal performance enhancement techniques, and methodology for selecting PCM; as a result, assisting the researchers and engineers in choosing the appropriate PCM for the various EV battery thermal management applications in terms of chemical, thermal, and economic aspects Graphical Abstract [ABSTRACT FROM AUTHOR]

Compared to the use of positive temperature coefficient (PTC) materials that consume electrical energy for low-temperature heating, heat pump air conditioners can provide more energy-efficient heating performance by absorbing and utilizing heat from the outdoor air to heat the cab in order to improve the range of electric vehicles. In addition, in order to make the battery work under safe working conditions, this paper proposes battery thermal management coupled with vapor injection heat pump air conditioning. The system is modeled and analyzed through simulation, and the impact of the compressor speed and ambient temperature changes in the battery cooling performance of the system. The results show that under different compressor RPM (Revolution Per Minute) with an ambient temperature of 5 °C, the average temperature of the battery pack remains below 30 °C, and the majority of individual cell temperatures are maintained within the range of 20 to 35 °C. At a constant compressor RPM of 4000/min under varying ambient temperatures, the average temperature of the battery pack remains below 30 °C, with the majority of individual cell temperatures staying within the range of 20 to 35 °C. And the battery cooling performance still performs well. In the low temperature of −10 °C and −20 °C, the system can still maintain a relatively stable heating capacity compared with the 2009.1W, provided by the environment temperature of 5 °C at the same RPM. [ABSTRACT FROM AUTHOR]

This paper introduces a novel hybrid thermal management strategy, which uses secondary coolants (air and fluid) to extract heat from a phase change material (paraffin), resulting in an increase in the phase change material's heat extraction capability and the battery module's overall thermal performance. A novel cold plate design is developed and placed between the rows and columns of the cells. The cold plate contains a single fluid body to improve the thermal performance of the battery module. Experimental studies were conducted to obtain the temperature and heat flux profiles of the battery module. Moreover, a numerical model is developed and validated using the experimental data obtained. The numerical data stayed within ±2% of the experimental data. In addition, the ability of nanoparticles to increase the thermal conductivity of water is examined and it is found that the cooling from the liquid cooling component is not sensitive enough to capture the 0.32 W/m K increase in the thermal conductivity of the fluid. Furthermore, in order to enhance the air cooling, fins were added within the air duct to the cold plate. However, this is not feasible, as the pressure drop through the addition of the fins increased by ~245%, whereas the maximum temperature of the battery module reduced by only 0.6 K. Finally, when scaled up to an entire battery pack at a high discharge rate of 7 C, the numerical results showed that the overall temperature uniformity across the pack was 1.14 K, with a maximum temperature of 302.6 K, which was within the optimal operating temperature and uniformity ranges. Therefore, the developed thermal management strategy eliminates the requirement of a pump and reservoir and can be scaled up or down according to the energy and power requirements. [ABSTRACT FROM AUTHOR]

This study focused on the design of a battery pack cooling channel based on a Tesla Model S electric car. This study aimed to achieve a balance between cooling efficiency and pressure drop while maintaining safe and optimal operating temperatures for the batteries. A cooling channel design similar to the basic type employed in the Tesla Model S using 448 cylindrical Li-ion batteries was considered. Consequently, important parameters, such as the maximum temperature and temperature difference in the battery cells in a module, as well as the pressure drop of the coolant, were analyzed. In addition, the characteristics of the temperature changes in each cooling channel shape were investigated. The temperature limit for the battery in a module and the temperature limit difference were set to 40 °C and 5 °C, respectively, to evaluate the performance of the cooling system. Further, the effects of discharge rates (3C and 5C), cooling channel shapes (counter flow and parallel types), and coolant inlet velocities (0.1, 0.2, 0.3, and 0.4 m/s) on battery thermal management were analyzed. The results revealed that the parallel type channel yielded a lower pressure drop than the basic type channel; however, it was not as effective in removing heat from the battery. In contrast, the counter flow type channel effectively removed heat from the batteries with a higher coolant pressure drop in the channel. Therefore, a multi-counter flow type cooling channel combining the advantages of both these channels was proposed to decrease the pressure drop while maintaining appropriate operating temperatures for the battery module. The proposed cooling channel exhibited an excellent cooling performance with lower power consumption and better heat transfer characteristics. However, relatively minimal differences were confirmed for the maximum temperature and temperature difference in the battery module compared with the counter flow type. Therefore, the proposed cooling channel type can be implemented to ensure the optimal temperature operation of the battery module and to decrease system power consumption. [ABSTRACT FROM AUTHOR]

Excessive temperature of battery pack causes the performance degradation, affecting the normal operation and safety of the electric vehicles (EVs). This paper proposes an ant colony optimization-fuzzy sliding mode control (ACO-FSMC) hierarchical strategy for the battery thermal management system (BTMS) of EVs. Ignoring the dynamic process of the pump and compressor leads to the deviation of the cooling efficiency of EVs. Therefore, a control-oriented BTMS model is established to describe the temperature dynamics of battery pack and coolant, considering driving current effect on the speed of pump and compressor. Then, a hierarchical optimization strategy is designed to realize the control of the battery cooling rate as well as the speed of the pump and compressor. The upper layer of controller use an ant colony optimization (ACO) to solve the reference speed of the pump and compressor while satisfying constraints of physical characteristics of actuators, aiming at reducing battery temperature deviation and saving energy of BTMS. Considering the nonlinearity of lower layer of BTMS caused by the disturbance of time-varying load torque, fuzzy sliding mode control (FSMC) is applied to control the speed of pump and compressor, in which an integral sliding surface is designed to reduce the influence of disturbance. In order to weaken the chattering of sliding mode control and reduce energy consumption, fuzzy controller is used to adjust the reaching law parameters of sliding mode surface. The simulation results show that compared with PID, the maximum temperature deviation of ACO-FSMC is reduced by 43%, and the energy consumption is reduced by 23%. • A control-oriented battery thermal management model is established. • The dynamic process of the pump and compressor is considered. • ACO is used to solve the reference speed of the pump and compressor. • Fuzzy sliding mode control is applied to weaken the chattering of system. • The cooling performance and energy saving of the proposed method is verified. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, the effects of battery thermal management (BTM), pumping power, and heat transfer rate were compared and analyzed under different operating conditions and cooling configurations for the liquid cooling plate of a lithium-ion battery. The results elucidated that when the flow rate in the cooling plate increased from 2 to 6 L/min, the average temperature of the battery module decreased from 53.8 to 50.7 °C, but the pumping power increased from 0.036 to 0.808 W. In addition, an increase in the width of the cooling channel and number of channels resulted in a decrease in the average temperature of the battery module and a reduction in the pumping power. The most influential variable for the temperature control of the battery was an increase in the flow rate. In addition, according to the results of the orthogonal analysis, an increase in the number of cooling plate channels resulted in the best cooling performance and reduced pumping power. Based on this, a cooling plate with six channels was applied to both the top and bottom parts, and the top and bottom cooling showed sufficient cooling performance in maintaining the average temperature of the battery module below 45 °C. [ABSTRACT FROM AUTHOR]

The primary objective of this study was to explore the impact of integrating nano-additives on heat transfer enhancement within an LHTES (Latent Heat Thermal Energy Storage) system. Our findings revealed that introducing a minimal amount of nano-materials (less than 5.0 vol%) into the Phase Change Material (PCM) led to a remarkable alignment between experimental correlations and mixture models. Furthermore, employing the mixing model allowed for the accurate prediction of outcomes. In the current context of scientific research, there is a strong endorsement for the widespread adoption of Electric Vehicles (EVs) as a sustainable alternative to Internal Combustion Engines (ICEs), crucial for advancing decarbonization and mitigating climate-related crises. Lithium-ion batteries are the predominant choice for EVs and various electrical devices. However, the operational challenges posed by high temperatures, impacting their lifespan, charge/discharge cycles, and the risk of thermal runaway, necessitate effective thermal management systems. Given this background, our study focuses on simulating the heat dissipation of a single cylindrical Li-ion battery cell employing a Nano-enhanced Phase Change Material (NePCM)-based cooling system. We also introduce a novel fin design in this work. Through comprehensive analysis, we examine the performance of battery modules utilizing PCM and NePCM at different discharge rates, both with and without the newly proposed fin design. Our research demonstrates that the incorporation of fins and nanoparticles into PCM significantly enhances heat transfer and reduces the charging time compared to the base PCM. Notably, carbon-based nanoparticles outshine their metal-based counterparts in terms of melting rate and maintaining a uniform temperature profile within the battery. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, an experimental and numerical study was conducted to analyze the performance of a hybrid thermal management concept for cylindrical lithium-ion battery modules at various discharge rates. The proposed concept consists of primary cooling through phase change material (PCM) and secondary cooling through vertical liquid channels between the PCM and airflow at the top of the cells. Two experimental studies were performed to obtain the temperature and heat flux profiles. In addition, the thermal performance of the battery module was obtained for 1 C, 2 C, 3 C, 5 C, and 7 C discharge rates using the numerical study. The results show that the maximum temperature was limited to ~30 °C. Additionally, the temperature uniformity in all the discharge rates was maintained below 5 °C. Finally, a meager amount of PCM was utilized during all the discharge cycles. At 1 C none of the PCM changed its phase, whereas at 2 C, 0.32%, 3 C, 0.14%, 5 C, 0.3%, and at 7 C, 0.12% of PCM changed its phase. The proposed hybrid concept can maintain the thermal environment required by the Li-ion cells for effective performance. Furthermore, this concept does not require excessive pumping fluid power and high air velocities, which reduces the energy required for the operation of the thermal management system, thereby increasing the available energy for propulsion. [ABSTRACT FROM AUTHOR]

Electrification on transportation and electricity generation via renewable sources play a vital role to diminish the effects of energy usage on the environment. Transition from the conventional fuels to renewables for transportation and electricity generation demands the storage of electricity in great capacities with desired power densities and relatively high C-rate values. Yet, thermal and electrical characteristics vary greatly depending on the chemistry and structure of battery cells. At this point, lithium-ion (Li-ion) batteries are more suitable in most applications due to their superiorities such as long lifetime, high recyclability, and capacities. However, exothermic electrochemical reactions yield temperature to increase suddenly which affects the degradation in cells, ageing, and electrochemical reaction kinetics. Therefore, strict temperature control increases battery lifetime and eliminates undesired situations such as layer degradation and thermal runaway. In the literature, there are many distinct battery thermal management strategies to effectively control battery cell temperatures. These strategies vary based on the geometrical form, size, capacity, and chemistry of the battery cells. Here, we focus on proposed battery thermal management strategies and current applications in the electric vehicle (EV) industry. In this review, various battery thermal management strategies are documented and compared in detail with respect to geometry, thermal uniformity, coolant type and heat transfer methodology for Li-ion and post-lithium batteries. [ABSTRACT FROM AUTHOR]

The hybrid fuel cell/battery technology is an attractive option for a sustainable mobility with zero emissions. In fact, this solution owns system scalability features and high efficiency and, compared to battery electric solutions, it offers advantages in terms of flexibility of use and fast charging times. However, the thermal management for the battery in this type of powertrain is a crucial issue, since operating temperatures can significantly affect safety and performance. In this study, an innovative system aimed at providing high storage energy density and improving the battery pack performance of hybrid fuel cell/battery vehicles is investigated for use on-board of a plug-in fuel cell electric bike. The proposed system, developed by the authors in previous studies, integrates the battery pack with a hydrogen storage based on metal hydrides. The idea behind this solution is to exploit the endothermic desorption processes of hydrogen in metal hydrides to cool down the battery pack during operation. An experimental analysis is conducted to assess the thermal management capabilities of this system: by considering a typical duty cycle designed on the base of road test measurements, battery pack temperature profiles are evaluated and compared against those from a control experiment where no battery thermal management is enabled (i.e. no hydrogen desorption from the metal hydride tank). The results show that, beside enhancing the on-board stored energy capacity, the proposed system represents an effective solution to provide an efficient thermal management for the battery pack, with significant advantages in terms of attainable riding range. • Plug-in fuel cell electric bicycle with greater riding range than e-bike. • On-board storage system integrating metal hydrides tank and battery pack. • Enhanced volumetric and gravimetric on-board energy storage density. • Optimal thermal management of battery pack and metal hydride tank. [ABSTRACT FROM AUTHOR]

The accumulation of thermal energy in the form of latent heat of phase transition using phase change materials (PCMs) is one of the most attractive and studied research areas with huge application potential in both passive and active technical systems. The largest and most important group of PCMs for low-temperature applications are organic PCMs, mainly paraffins, fatty acids, fatty alcohols, and polymers. One of the major disadvantages of organic PCMs is their flammability. In many applications such as building, battery thermal management, and protective insulations, the crucial task is to reduce the fire risk of flammable PCMs. In the last decade, numerous research works have been performed to reduce the flammability of organic PCMs, without losing their thermal performance. In this review, the main groups of flame retardants, PCMs flame retardation methods as well as examples of flame-retarded PCMs and their application areas were described. [ABSTRACT FROM AUTHOR]

Adhering to the thermal management requirements of prismatic battery modules, an improved lightweight parallel liquid cooling structure with slender tubes and a thin heat-conducting plate is proposed. The multiobjective optimization of the structure, operating parameters of the thermal management system, and thermal characteristics of a battery module are carried out. The effects of the equivalent diameter of the square tubes and the inner diameter of the circular tubes on the maximum temperature, maximum temperature difference of the batteries, and coolant pressure drop of liquid cooling battery thermal management system (BTMS) are investigated. The more significant factors, selected as the design variables, are the equivalent diameter of the square tubes, the inner diameter of the circular tube, and the coolant inlet velocity. Combining the computational fluid dynamics (CFD) method with multiobjective optimization, the different conditions of heat management parameters obtained by Latin hypercube sampling are numerically calculated, and the optimization of these parameters is carried out by the second-generation Elitist Nondominated Sorting Genetic Algorithm (NSGA-II). Compared with the thermal characteristics of the battery module before optimization, the maximum temperature of the module after optimization is reduced by 9.3%, the maximum temperature difference is reduced by 20.7%, and the coolant pressure drop from inlet to outlet is reduced by 49.1%. [ABSTRACT FROM AUTHOR]

Paraffin phase change materials (PCMs) exhibit great potential in battery thermal management (BTM); nevertheless, their application has been hampered by the handicap of low thermal conductivity, leakage, and volume expansion during phase transition. In this work, ternary composite PCMs formed of paraffin, expanded graphite (EG), and low-density polyethylene (LDPE) were developed for application in BTM. The structure and properties of the composite PCMs were characterized via X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, and thermal constant analysis. The result shows that EG can form a large-size graphite frame as heat conduction paths to improve the thermal conductivity of the composite PCM, and LDPE can form an interpenetrating network within the composite PCM to resist the internal stress of paraffin expansion and prevent deformation. The latent heat and thermal conductivity of the composite PCMs loaded with 10 wt% EG and 4 wt% LDPE can reach 172.06 J/g and 3.85 Wm−1K−1 with a relatively low leakage ratio of 6.2 wt%. Remarkably, the composite PCMs could reduce the temperature rise of the battery by 55.1%. In brief, this work provides a feasible route to develop high-performance PCMs for BTM. [ABSTRACT FROM AUTHOR]

The selection of a battery thermal management technique is important to overcoming safety and performance problems by maintaining the temperature of batteries within a desired range. In this study, a LiFePO4 (LFP) pouch-type battery having a capacity of 20 Ah was experimentally cooled with both air and liquid (immersion cooling) techniques. Distilled water was selected as the immersion fluid in the experiments, and the impact of discharge rate (1–4C), immersion ratio (50–100%), and coolant fluid inlet temperature (15–25 °C) on the battery temperature were investigated during the discharge period. The experiments revealed that maximum temperatures were reached at approximately 45 °C and 33 °C for air and distilled water cooling techniques, respectively, at the discharge rate of 4C. The average and maximum battery surface temperatures can be reduced by 28% and 25%, respectively, with the implementation of the liquid immersion technique at the discharge rate of 4C compared to the air technique. Moreover, the experiments demonstrated that the maximum temperature difference could be lowered to 4 °C by means of 100% liquid immersion cooling at the highest discharge rate, where they are approximately 11 °C and 12 °C for air and 50% for immersion cooling, respectively. In addition, it was observed that the coolant fluid inlet temperature has a significant impact on battery temperature for %100 liquid immersion. [ABSTRACT FROM AUTHOR]

• HVAC, drivetrain, and UBE are temperature-sensitive components in BEVs. • HVAC energy consumption has the greatest impact on BEV range. • Heat pump-based heating systems are more energy-efficient than resistive heaters. • Cold weather reduces powertrain and regenerative braking efficiency. • Low temperatures reduce UBE in BEVs, affecting range. This study investigates the impact of ambient temperature on the range of electric vehicles (EVs) by analyzing its effects on usable battery energy (UBE), heating, ventilation, and air conditioning (HVAC) energy consumption, and powertrain energy losses. Chassis dynamometer tests within a thermal chamber were conducted under various temperature conditions to investigate these impacts. The results indicate that lower temperatures lead to a decrease in UBE for lithium-ion batteries in EVs. At −18 °C, the UBE exhibited reductions of 4–––8 % compared to the UBE at 22 °C. Battery thermal management strategies significantly affected the UBE loss, with different strategies resulting in distinct UBE reductions. HVAC energy consumption, especially for interior heating, proved to be the most dominant variable affecting EV driving range. Larger discrepancies between the HVAC target temperature (22 °C) and the ambient temperature increased HVAC energy usage. The type of HVAC system also influenced energy consumption, where EVs equipped with heat pumps demonstrated lower energy consumption for heating compared to those relying solely on resistance heaters. Ambient temperature also influenced motor energy consumption due to increased frictions, powertrain losses and tire rolling resistance at lower temperatures; consequently, regenerative braking energy decreased in cold conditions. Combining these effects influenced the overall energy consumption and driving range of EVs. At −18 °C, the driving range saw a substantial decrease of up to 60 % compared to 22 °C, while a slight decrease was observed at 35 °C. [ABSTRACT FROM AUTHOR]

In this paper, a battery thermal management system (BTMS) integrating piezoelectric pump (PP) and thermoelectric coolers (TEC) was designed. In addition, phase change materials (PCM) were also added to the system. When the battery pack was discharged uniformly, the driving frequency of PP was adjusted to ensure that the battery temperature does not exceed the limit value (318.15K) during discharge. A control strategy was designed to adjust the driving frequency of the PP according to the temperature of the outlet coolant and discharge rate of battery when the battery discharge was not uniform, which can ensure that the temperature difference between battery packs does not exceed the limit value (5K). In addition, the suppression effect of thermal management system on thermal runaway under different TEC current was also studied. The experimental and simulation results showed that when the battery pack was discharged uniformly at 2C or 3C, and the driving frequency of the PP was 40HZ and 60HZ respectively, the battery temperature does not exceed the limit and the PCM can be completely transformed to be fully utilized. According to the control strategy, the battery temperature uniformity can be ensured. In addition, the thermal runaway propagation can be effectively inhibited when the TEC current is 4A. • Piezoelectric pump and thermoelectric cooler are integrated for thermal management. • A driving frequency control strategy of piezoelectric pump is presented. • The battery temperature and temperature uniformity are analyzed comprehensively. • The thermal runaway suppression effect is analyzed. [ABSTRACT FROM AUTHOR]

The growing development of lithium-ion battery technology goes along with the new energy storage era across various sectors, e.g., mobility (electric vehicles), power generation and dispatching. The need for sophisticated modeling approaches has become a crucial tool to predict and optimize battery behavior given the demand of ever-higher performance, longevity, and safety. This review integrates the state-of-the-art in lithium-ion battery modeling, covering various scales, from particle-level simulations to pack-level thermal management systems, involving particle scale simplifications, microscale electrochemical models, and battery scale electrical models with thermal and heat generation prediction. Beyond that, authors highlight the growing trend in integrating highly accurate physics-based with thermal approaches such as the electrochemical-thermal coupled model to fully answer the multiscale challenges. Through capturing the electrochemical phenomena and thermal dynamics, and developing a comprehensive understanding of battery kinetics, safety risks such as thermal runaway can be thoroughly mitigated. Authors emphasize the trade-offs between computational efficiency and model complexity, explaining the limitations, strengths, and applications of diverse modeling approaches. This review illuminates the integration of battery management systems and cooling strategies. • Lithium-ion battery electrochemical and thermal dynamics are comprehensively reviewed. • Multiscale modeling is analyzed, considering physical limits and computational costs. • Systematic physics-based model comparison: strengths and limitations are detailed. • Scale-specific physical complexities are schematized for clarity. [ABSTRACT FROM AUTHOR]

[Display omitted] • An exhaustive analysis of heat generation and thermal issues in batteries is discussed. • A comprehensive examination of diverse battery cooling methods is reviewed. • The integration of PCM and NePCM into batteries and their subsequent performance were reviewed. • The economic viability of BTM systems utilizing PCM/NePCM is extensively scrutinized. • The comprehension of BTMS challenges and prospective avenues for further study are emphasized. The widespread adoption of lithium-ion (Li-ion) batteries in electric and hybrid vehicles has garnered significant attention due to their high energy density, impressive power-to-mass ratio, and extended lifespan. However, challenges like non-uniform temperature distribution, suboptimal energy storage, and slower release rates have surfaced. The rising incidents of battery explosions underscore the urgent need for a thorough understanding of Li-ion battery technology, particularly in thermal management. This knowledge is vital for maintaining batteries within an optimal temperature range, improving operational efficiency, and ensuring stability and safety. This review section meticulously explores critical aspects of battery thermal management, focusing on the process of heat generation and transfer within the cell and module. It also examines the thermal management challenges through active and passive techniques, emphasizing advancements in heat transfer methodologies. The investigation of integrating nano-enhanced phase change materials (NePCMs) with Li-ion batteries is particularly noteworthy as a promising approach to enhance thermal conductivity and management. The review comprehensively elaborates on the functions, strategies, emerging concerns, integration methodologies, and benefits of NePCMs, thoroughly examining their impact on thermal management. This comprehensive review anticipates advancements in this vital domain, envisioning development trends and prospects associated with the application of NePCMs in battery thermal management. [ABSTRACT FROM AUTHOR]

Renewable energy, in particular, is critical for a sustainable world. Effective storage of energy is at the heart of all systems. While energy storage allows us to preserve the beauties offered by nature, it also requires innovative solutions that push the limits of technology. The most important factor affecting the performance of batteries is their temperature. For this reason, the serpentine cooling model, which is an innovative battery cooling method, was evaluated in this study. Generally, in the literature, batteries are considered as heat masses and given a certain heat flux and their temperature distributions are examined. In this study, batteries were connected to each other with busbars as in reality and thermal analyses were performed. In addition, a serpentine cooling method, which has never been used before, was tried as a cooling method in batteries. While all these evaluations were made, statistical analyses were performed for the priority order of the parameters used. All of these situations show how innovative the study is. The NTGK model was used in CFD analyses. 5 different parameters were considered. These are the discharge rate (0.5C, 1C, 1.5C, 2C and 2.5C), the type of refrigerant (air and water), the speed at which the refrigerant enters the model (0.01 m/s, 0.03 m/s and 0.05 m/s), the ambient temperature (293K, 298K and 300K), and the SOH value (50 %, 65 %, 75 %).Water has been shown to be a better refrigerant than air. As the inlet speed of the refrigerant was increased, the discharge rate was reduced, and the SOH value decreased, the temperature values obtained by the model were lower. The temperature values of the batteries according to their location in the model were also examined. 5-factor, 2-level experiments were conducted to examine statistically. It was checked whether the created values fit the distributions and it was seen that the most effective parameter used in the model was the type of refrigerant. In addition, the most statistically effective working conditions were also determined. • The NTGK model was used in the CFD analysis of the batteries. • The batteries were connected to each other with busbars. • According to statistical analysis, the most effective parameter is the cooler type. [ABSTRACT FROM AUTHOR]

The hybrid battery thermal management system (BTMS), suitable for extreme fast discharging operations and extended operation cycles of a lithium-ion battery pack with multiple parallel groups in high temperature environment, is constructed and optimized by combining liquid cooling and phase change materials. Compared to water cooling, the temperature and temperature difference of batteries with hybrid cooling can be decreased by up to 4.86 °C and 6.94 °C, respectively. The distance between neighboring batteries is discussed to simplify the arrangement of the hybrid BTMS, reducing mass and volume by 4.56 % and 7.75 %, respectively. Under 40 °C environment and 5C discharge conditions, the temperature difference and maximum temperature of the optimized lightweight system have been regulated to within 3.06 °C and 46.56 °C, respectively. Then, the heat accumulation during continuous operation is effectively suppressed by adding efficient laying-aside cooling during the cyclic charging and discharging process, decreasing the temperature and temperature difference by up to 4.88 °C and 3.39 °C, respectively. In summary, the lightweight hybrid BTMS reduces the complexity of traditional thermal management system while ensuring cooling performance, and the designed effective intermittent cycle operation strategy introduces a new perspective for efficient BTMS. • The preferred hybrid cooling is suitable for high temperature and extreme conditions. • The mass and volume of optimized system are separately reduced by 4.56 % and 7.75 %. • Laying-aside cooling process after discharge of battery pack is thoroughly explained. • The efficient cycle charging and discharging strategies are designed and selected. • Lightweight design and intermittent cycle operation strategy offer new perspectives. [ABSTRACT FROM AUTHOR]

• A novel bionic lotus leaf (BLL) liquid cooling plate firstly proposed. • The heat performance of BLL channels and serpentine (SP) channels compared. • The influence of different structures is analyzed by single factor. • Parameters of BLL channels optimized by orthogonal analysis method. Battery Thermal Management Systems (BTMS) are pivotal in safeguarding the safety, efficiency, and lifespan of electric vehicles. In this study, we propose a bionic lotus leaf (BLL) channel liquid-cooled plate to mitigate temperature accumulation issues observed during lithium-ion battery (LIB) discharge. The primary objective is to enhance heat dissipation and achieve uniform temperature distribution within LIBs. We investigated the impact of different interior configurations and mass flow rates on individual lithium-ion battery (LIB) temperatures using single-variable analysis. Our findings indicate that higher inlet mass flow rates effectively lower the temperature increase in individual LIBs, albeit at the cost of inducing a significant pressure drop. The optimal parameter combination is determined through orthogonal analysis. Specifically, the channel angle (α) and inlet mass flow rate (M) are found to significantly influence the maximum temperature (T max) of LIBs. The number of channels (N) is optimized to enhance temperature distribution and reduce maximum temperature variation (ΔT max) within LIBs. Furthermore, adjusting the channel width (D) substantially mitigated pressure drop (ΔP) in the BLL channel liquid cooling plate, thereby improving hydraulic pump efficiency. The identified optimal combination (M = 1.0 g s-1, N = 4, D = 2.5 mm, α = 90°) ensures that T max remains below 29.732 °C even during a 5C discharge, a critical requirement. Compared to a traditional serpentine channel with equivalent heat transfer area and inlet mass flow, the optimized BLL channel showed a decrease in T max by 0.776 °C, ΔT max reduction by 2.445 °C, and ΔP reduced to only 43.44 % of that in the serpentine channel. The BLL channel proposed in this research can serve as a valuable reference for BTMS. [ABSTRACT FROM AUTHOR]

Based on liquid cooling and phase change material (PCM), a fin-enhanced composite thermal management system suitable for high power and extended cycle operations of lithium-ion battery module at high ambient temperature is proposed in this work. The coupling effect between the protruding fin structure and PCM thickness, as well as the addition of expanded graphite to the PCM, are investigated to optimize hybrid cooling arrangement. The results show that synergistic optimization of the protruding fin structure and PCM arrangement can enhance heat diffusion from the batteries to the cooling water, improve PCM utilization, and ensure sufficient latent heat. And then, the expanded graphite-modified PCM can make heat absorption and phase transition more uniform, and battery temperatures can be further decreased by up to 7.45 °C with 16 wt% expanded graphite. Clearly, the coupling optimization improves the cooling performance and applicability of conventional thermal management systems, while the temperature difference and maximum temperature in the optimized system have been regulated to within 4.30 °C and 46.78 °C under 40 °C environment and 5C discharge, respectively. Moreover, the cyclic charging and discharging strategies are designed and matched, and using the matching strategy with a fixed charge or discharge rate of 1C provides lower temperatures and better temperature uniformity, which can always control the temperatures below 47.22 °C and temperature difference below 4.69 °C. The optimized system with cycle strategy matching ensures the repeatability of battery operation and provides cooling solutions for different application scenarios. • Hybrid cooling system is preferred for batteries in high power and cyclic operations. • The protruding fin structure and PCM arrangement are coupled optimized and balanced. • The T max and Δ T max are separately controlled within 46.8 °C and 4.3 °C at 5C discharge. • Matching strategy with fixed 1C charge or discharge ensure repeatability of battery. • Optimized system and cycle strategy give cooling solutions for different application. [ABSTRACT FROM AUTHOR]

An efficient Battery Thermal Management System (BTMS) is vital for maximizing electric vehicle effectiveness and extending service life, essential for sustainable transportation. This study proposes a novel non-uniform nano-PCM distribution strategy within BTMS to tackle battery overheating challenges and further proposes a multi-objective optimization framework combining Back Propagation Neural Networks (BPNN) and Genetic Algorithm (GA) to achieve optimal design solutions for BTMS. Optimization data is derived from the well-validated Lattice Boltzmann Method (LBM) results across 343 cases. Initial evaluations show that a negative gradient distributed nano-PCM (Type 2) improves melting rate, heat dissipation power, and temperature uniformity by 4.67%, 4.87%, 19%, and 7.0%, respectively. The BPNN-GA optimization framework satisfactorily correlates nanoparticle distribution with four evaluation metrics, achieving R 2 values from 0.9469 to 0.9987. Optimization improves melting rate, heat dissipation power, and regional and inter-regional temperature uniformity by 9.13%, 9.94%, 7.77%, and 29.73%, respectively. The BPNN-GA also demonstrates reasonable generalizability for the other two practical case scenarios with improvements in certain criteria up to 49.19%. This study highlights the potential of uneven nano-PCM configurations and the efficiency of the LBM-BPNN-GA framework in achieving superior thermal management for BTMS, which is expected to provide insights for future BTMS designs and implementations. [Display omitted] • A novel non-uniform distributed Nano-PCM configuration with BTMS is proposed. • Cooling performance of Nano-PCM is assessed via LBM studies across 343 cases. • A novel multi-objective optimization framework using BPNN and GA is proposed. • A negatively gradient-distributed Nano-PCM shows superior cooling performance. • BPNN-GA framework successfully improved multiple evaluation met-rics up to 29.73%. [ABSTRACT FROM AUTHOR]

To enhance the operating performance of the lithium-ion battery module during high-rate discharge with lower energy consumption, a novel embedded hybrid cooling plate (EHCP) coupled with wavy liquid cooling channels and phase change material (PCM) was proposed for the thermal management of a prismatic battery module. The numerical model of the battery thermal management system (BTMS) was developed and validated by experimental data. The effects of key operating parameters on the thermal management performance were systematically investigated through single-factor analysis. Three different control strategies were compared, and the time-based early shutdown strategy exhibited a better performance in reducing the maximum temperature difference and flow energy consumption for active cooling. Then, a reliable multi-objective optimization algorithm (MOGA) was adopted to obtain the optimal operating parameters of the BTMS including PCM thermophysical properties, coolant inlet temperature and velocity, and liquid cooling shutdown time. The result showed that the maximum temperature and maximum single-cell temperature difference of the battery module could be controlled at 39.75 °C and 4.91 °C, while the flow energy consumption was reduced by 80.80 % compared to the continuous liquid cooling mode under 3C discharge with an ambient temperature of 30 °C. These results imply that the proposed BTMS has adequate thermal management capacity and the potential for practical application. • A novel cooling plate combining wavy channels and phase change material is proposed. • The Time-based early shutdown strategy can effectively improve thermal performance. • The operating parameters are optimized by a multi-objective genetic algorithm. • The battery temperature is suitable and the flow energy consumption is reduced by 80.80 %. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are commonly employed in electric and hybrid electric vehicles as the power source; however, they generate enormous heat during charging/discharging. Exceeding the desirable temperature range (20–40 °C) may detrimentally affect battery longevity, leading to thermal runaway. We studied the thermal response of an air-cooled battery thermal management system with alterations to cell arrangements, battery sidewalls, inflow/outflow configurations, and varying thicknesses of phase change material (PCM). A battery pack of cylindrical lithium-ion cells underwent comprehensive numerical testing at 1C and 3C discharge rates. The aim was to examine the impact of geometrical and flow modifications on the thermal performance. The evaluation focused on the average/maximum cell temperature, thermal uniformity, pressure drop, and performance evaluation criteria. At 1C, the zig-zag cell arrangement and trapezoidal/step walls delivered superior heat dissipation, reducing the maximum temperatures by 5 K (zig-zag) and 10 K (trapezoidal/step) compared to base cases with air cooling only. Furthermore, applying a 1 mm PCM significantly lowered the maximum temperature by 40 K (11.1 %) and improved the thermal uniformity by 24.4 K (79.7 %) compared to scenarios without PCM, particularly at 3C. Notably, the PCM thickness of 1.5 mm emerged as the most cost-effective solution for efficiently maintaining the battery temperature. • A comparative analysis on lithium-ion battery thermal management was done. • Wall shape, cell arrangement, flow configuration, and PCM thickness were varied. • Zig-zag cells, and trapezoidal/step battery walls yielded the best cooling. • A reduction of 2-3 K is achievable with different inlet/outlet configurations. • Notable drop in temperature by 40 K was noticed with 1 mm PCM thickness. [ABSTRACT FROM AUTHOR]

Refrigerant indirect contact phase-change cooling system flows refrigerant into a cold plate and utilizes the phase-change to exchange heat with the battery. However, R134a, commonly used, is being gradually restricted due to its environmental impact. A new kind of near azeotrope mixed refrigerant R1234yf/R152a (mass ratio 60.5:39.5) is proposed under environmental protection and safety. Based on the fluid-structure interaction model, the evaluation of different indirect contact phase-change cooling systems for battery thermal management (BTM) using R1234yf/R152a is investigated. After obtaining battery (150 Ah, 3.2 V LiFePO4) parameters, heat generation power, and main test conditions through experiments, the thermal properties are numerically studied by computational fluid dynamics (CFD). At 1 C discharge rate, the temperature gradient (TG) of single battery and the maximum temperature difference (TD) among batteries are analyzed for two cases: The maximum TD among batteries of Case_b is 6.5°C lower than that of Case_a. In addition, the effect of the mixed refrigerant and traditional liquid cooling on the battery temperature is studied at different evaporation temperatures (ETs) (20°C, 25°C) and different mass flow rates (MFRs) (0.02, 0.10, and 0.18 kg/s). The results show that both the increase of inlet MFR and the reduction of inlet ET may significantly improve the battery module cooling rate. Compared with 0.02 kg/s, as the MFR increases, the temperature drop slopes to 9.56 and 11.2 at 20°C. The battery module temperature uniformity is improved with the increase of ET. Overall, the mixed refrigerant has advantages in temperature uniformity and consistency. The new mixed refrigerant plays a positive role in controlling battery temperature. [ABSTRACT FROM AUTHOR]

In a battery cooling system, by adopting a cooling optimization control strategy, the battery temperature under different external environments and load currents can be adjusted to ensure performance and safety. In this study, two modes of the thermal management system are established for the 6s4p (six serial and four parallel batteries in a stage) battery pack. A single particle model, considering battery aging, is adopted for the battery. Furthermore, a cooling optimization control strategy for the battery is proposed based on the triple-step nonlinear method, and then the optimization effect is validated under two C-rate charge–discharge cycles, NEDC cycles, and US06 cycles. Moreover, an extended PID control strategy is constructed and compared with the triple-step nonlinear method. A comparison of pump power, thermal behavior, and aging performance indicate parallel cooling is more advantageous. This verifies the validity of the triple-step nonlinear method and shows its advantages over the extended PID method. The present study provides a method to investigate the thermal behavior and aging performance of a battery pack in a BTM system, and fills in the research gaps in the cooling optimization control strategy for battery packs. [ABSTRACT FROM AUTHOR]

Battery pack specific energy, which can be enhanced by minimising the mass of the battery thermal management system (BTMS), is a limit on electric fixed-wing flight applications. In this paper, the use of phase-change materials (PCMs) for BTMSs is numerically explored in the 3D domain, including an equivalent circuit battery model. A parametric study of PCM properties for effective thermal management is conducted for a typical one-hour flight. PCMs maintain an ideal operating temperature (288.15 K–308.15 K) throughout the entire battery pack. The PCM absorbs heat generated during takeoff, which is subsequently used to maintain cell temperature during the cruise phase of flight. In the control case (no BTMS), battery pack temperatures fall below the ideal operating range. We conduct a parametric study highlighting the insignificance of PCM thermal conductivity on BTMS performance, with negligible enhancement observed across the tested window (0.1–10 W m−1 K−1). However, the PCM's latent heat of fusion is critical. Developers of PCMs for battery-powered flight must focus on enhanced latent heat of fusion, regardless of the adverse effect on thermal conductivity. In long-haul flight, an elongated cruise phase and higher altitude exasperate this problem. The unique characteristics of PCM offer a passive low-mass solution that merits further investigation for flight applications. [ABSTRACT FROM AUTHOR]

To improve the operating performance of the large-capacity battery pack of electric vehicles during continuous charging and discharging and to avoid its thermal runaway, in this paper we propose a new hybrid thermal management system that couples the PCM with the liquid cooling plate with microchannels. The flow direction of the microchannel structure in the bottom plate is designed according to the characteristics of the large axial thermal conductivity of the battery, and the cooling performance of the whole system under continuous charge/discharge cycles is numerically simulated. The results show that the hybrid PCM/liquid cooling plate can maintain good cooling performance under the discharge process of a large-capacity battery pack. After each cycle the temperature of the battery pack can be reduced to less than 30°, and the maximum temperature change rate of multiple cycles is controlled within 0.8%. With the application of the hybrid PCM/liquid-cooled plate battery cooling system, a safe temperature range of the battery pack is ensured even under multiple cycles of charging and discharging. The present work can facilitate future optimizations of the thermal management system of the large-capacity battery pack of electric vehicles. [ABSTRACT FROM AUTHOR]

[Display omitted] • The thermal application of carbon nanotube from waste plastic was firstly studied. • The thermal conductivity of phase change composite material increased by 104%. • Latent heat capacity of phase change composite material retains 90.7%. • The produced carbon nanotube shows similar potential as commercial carbon nanotube. • This phase change nanocomposite is promising for battery thermal management. Carbon nanotube (CNT), has been demonstrated as a promising high-value product from thermal chemical conversion of waste plastics and securing new applications is an important prerequisite for large-scale production of CNT from waste-plastic recycling. In this study, CNT, produced from waste plastic through chemical vapor deposition (pCNT), was applied as a nanofiller in phase change material (PCM), affording pCNT-PCM composites. Compared with pure PCM, the addition of 5.0 wt% pCNT rendered the peak melting temperature increase by 1.3 ℃, latent heat retain by 90.7%, and thermal conductivity increase by 104%. The results of morphological analysis and leakage testing confirmed that pCNT has similar PCM encapsulation performance and shape stability to those of commercial CNT. The formation of uniform pCNT cluster networks allowed for a large CNT loading into the PCM on the premise of free phase change, responsible for the high thermal conductivity inside the homogeneous phase. Thus, the resulting capillary forces retained a high latent heat capacity and suitable melting temperature and prohibited PCM leakage from the matrix to the outside during re-melting as the pCNT loading ratio increased. Therefore, the as-prepared pCNT-PCM composite is believed to have similar potential to cCNT and shows prominent performance as a flowable conductive filler for battery thermal management systems. [ABSTRACT FROM AUTHOR]

The battery thermal management system with phase change material coupled cold plates was investigated with the numerical simulation method. The results show that, the temperature and temperature difference of the battery pack decreases with the increase of the flow rates of the cold plate in the system, while the power consumption of the cold plate significantly increases, which leads to poor efficiency of the system. To improve the efficiency of the coupled thermal management system, an adjusting strategy was introduced to optimize the thickness distribution of phase change materials with the system volume fixed. The optimized results of typical cases show that, the optimal phase change material thickness distribution can be obtained by only 5 adjusting steps. Compared with the original system, the maximum temperature of the battery pack drops by 1.1 K and the temperature difference narrows down by 29% after the optimization. To achieve the same temperature difference in the battery pack, the power consumption of the optimized system lowers down by 64% compared with that of the original system. [ABSTRACT FROM AUTHOR]

Highlights: The phase change materials possess conformable configuration to the structure of Li-ion batteries in macro-scale and multidirectional thermal pathways for rapid and uniform heat transfer in micro-scale. Hierarchically structured phase change materials achieve dual-mode thermal management ability for heating and cooling Li-ion batteries. Excellent practical battery thermal management performance was verified by 18,650 Li-ion batteries in both cold and hot environments. Phase change materials (PCMs) are expected to achieve dual-mode thermal management for heating and cooling Li-ion batteries (LIBs) according to real-time thermal conditions, guaranteeing the reliable operation of LIBs in both cold and hot environments. Herein, we report a liquid metal (LM) modified polyethylene glycol/LM/boron nitride PCM, capable of dual-mode thermal managing the LIBs through photothermal effect and passive thermal conduction. Its geometrical conformation and thermal pathways fabricated through ice-template strategy are conformable to the LIB's structure and heat-conduction characteristic. Typically, soft and deformable LMs are modified on the boron nitride surface, serving as thermal bridges to reduce the contact thermal resistance among adjacent fillers to realize high thermal conductivity of 8.8 and 7.6 W m−1 K−1 in the vertical and in-plane directions, respectively. In addition, LM with excellent photothermal performance provides the PCM with efficient battery heating capability if employing a controllable lighting system. As a proof-of-concept, this PCM is manifested to heat battery to an appropriate temperature range in a cold environment and lower the working temperature of the LIBs by more than 10 °C at high charging/discharging rate, opening opportunities for LIBs with durable working performance and evitable risk of thermal runaway. [ABSTRACT FROM AUTHOR]

Liquid thermal management is the prevailing method to maintain the operating performance and safety of Li-ion batteries. However, a better heat transfer performance is often accompanied by a higher power cost for liquid-based cooling methods. In the present work, V-shaped intersecting bypasses are integrated into conventional serpentine channels to reduce the liquid pressure drop across the cold plate without loss of thermal performance. The thermal-hydraulic characteristics of the battery thermal management system are studied based on CFD simulations. The non-dimensional j/f factor is developed and adopted to evaluate the heat transfer ability and friction loss of different designs. The effects of intersecting channel addition, flow direction, channel inlet, and outlet distributions are explored with the simulation results and data analysis. The results show that all of these factors would impact the thermal–hydraulic characteristics of the liquid cold plate. The addition of intersecting channels remarkably reduces the power cost, thus increasing the j/f factor. The alteration of the flow direction from longitudinal to widthwise could further improve the thermal-hydraulic characteristics of the intersected channel design. For conventional serpentine channels, the inlet and outlet distributions show no evident impact on thermal performance. However, regarding the intersected cases, the thermal-hydraulic performance is enhanced when the inlet and outlet are placed on the opposite sides of the cold plate, especially when the inlet velocity is less than 0.3 m/s. The findings of this study could shed light on the liquid flow channel design for battery thermal management. [ABSTRACT FROM AUTHOR]