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The existing conventional vehicle transportation landscape in India is grappling with challenges stemming from extensive air pollution, health risks, surging oil prices, limited fossil fuel resources, substantial oil import expenses and energy volatility. To counter these issues, Electric Vehicles (EVs) are progressively replacing internal combustion engines, offering a promising route toward decarbonization and mitigating climate concerns. EVs rely on electric motors powered by batteries, predominantly Lithium-ion batteries (LIBs), known for their superior attributes such as low self-discharge, high energy density and extended life cycle. Nevertheless, LIB performance is significantly influenced by operating temperatures, with suboptimal conditions leading to decreased efficiency, power loss and faster aging. Addressing this, an effective Battery Thermal Management System (BTMS) becomes crucial to maintain batteries at optimal temperatures, enhancing their efficiency and safety. This study focuses on a computational analysis of passive heating systems employing Fins and Phase Change Materials (PCM) for 18650 Li-ion battery thermal management at low temperatures, with specific attention to battery module analysis. Numerical analysis using ANSYS FLUENT investigates the influence of varying PCM thickness on heat transfer, predicting temperature distribution and discussing its impact on battery output performance. [ABSTRACT FROM AUTHOR]

Because of their high energy capacity and power density, lithium‐ion batteries are an essential component of electric and hybrid vehicles; however, they frequently experience excessive temperature rise because of heat creation inside the batteries. The charge state and charge/discharge rate play a major role in this heat generation. Due to its high latent heat, compact design and lightweight nature without requiring any external power, passive techniques like phase change material (PCM) and heat pipe (HP) cooling have gained widespread popularity. Therefore, this work focussed on hybrid BTMS integrating Heat Pipe with PCM for better thermal management of battery pack supported by a heat pipe that is used to analyse the thermal performance of a battery module having three and four lithium‐ion batteries placed in series and parallel. The objective of maintaining temperature gradient of less than 5°C between the adjacent cells and maintaining the overall battery temperature in the range of 25°C–45°C has been successfully achieved. The results of experiments at various discharge rates showed that a heat pipe was crucial to quickly transferring heat and maintaining temperature homogeneity for PCM‐based battery modules. It can be concluded that the data presented above can offer views for creating and improving battery heat management systems. [ABSTRACT FROM AUTHOR]

In order to improve the performance of a battery thermal management system (BTMS) based on phase change material (PCM), expanded graphite (EG) is added to paraffin to form composite PCM (CPCM), and embedded aluminum fins are coupled with liquid cooling to enhance heat transfer. A heat generation model for lithium‐ion batteries (LIBs) is established and verified by experiments. The cooling performances of four BTMS designs were simulated. The effects of the thermal characteristics of LIBs were investigated at various velocities and directions of coolant flow as well as EG fractions in CPCMs. The simulation results indicate that Design IV shows a good cooling effect at a coolant flow rate of 0.06 m s−1 and an EG fraction of 12 wt%. Under ambient temperatures of 26°C, 35°C and 40°C, the maximum battery temperatures are 28.14°C, 37.15°C and 42.09°C, respectively, and the maximum temperature difference over the battery module is 1.88°C, 1.89°C and 1.92°C, respectively. The charge‐discharge cycle performances of the four BTMS designs were further investigated. In Design IV, the maximum temperature and the maximum temperature difference in the battery module remain unchanged during five cycles under 1, 2 and 3 C discharge rates. The new BTMS has significantly improved the secondary heat storage problem of PCMs and the temperature uniformity of LIBs. The fin structure combined with liquid cooling is efficient in enhancing the heat transfer of CPCM for battery thermal management. [ABSTRACT FROM AUTHOR]

Electric vehicles are seen as the prevailing choice for eco-friendly transportation. In electric vehicles, the thermal management system of battery cells is of great significance, especially under high operating temperatures and continuous discharge conditions. To address this issue, a pack-level battery thermal management system with phase change materials and liquid cooling was discussed in this paper. A dynamic electro-thermal coupled model for cells, the enthalpy–porosity model for phase change materials, and the k-ε model for the coolant flow were used. Various parameters, such as ambient temperatures, discharge rates, components of phase change materials, inlet mass flow rates, and temperatures of the coolant were considered. The results indicated that a battery thermal management system with both phase change materials and liquid cooling is more effective than the one with only liquid cooling. The phase change material with a mass fraction of 10% expanded graphite in paraffin wax had a favorable performance for the battery thermal management system. Additionally, increasing the mass flow rate or decreasing the flow temperature of the coolant can reduce the maximum temperature of the battery pack. However, the former can limit the maximum temperature difference, while the latter will deteriorate the temperature uniformity. The present work may shed light on the design of battery thermal management systems in the electric vehicle industry. [ABSTRACT FROM AUTHOR]

Electric vehicles with a pack of lithium-ion batteries (LIBs) are taking a significant place in the field of transportation. Since lithium-ion battery efficiency relies on battery pack temperature, the temperature of the battery pack must be maintained within the safe limits for proper working of the system. This paper proposes a novel experimental method to dissipate and maintain the thermal energy emitted by LIBs based on a nickel foam/paraffin composite and a composite of copper foam/paraffin for thermal management of Panasonic NCR 18650B cylindrical lithium-ion battery cells. The results indicate that the surface temperature of the battery is reduced by 30.95% by comparing with ambient air convection and 24% temperature reduction by comparing with PCM by the application of nickel foam at a 2C discharge rate. By using copper foam/paraffin composite 34% and 25% temperature reduction by comparing with ambient air convection and PCM (paraffin) accordingly was achieved at a 2C discharge rate. Additionally, the result of temperature uniformity on the thermal management of the battery pack was also studied. [ABSTRACT FROM AUTHOR]

Thermal runaway propagation of the power battery pack is an essential factor affecting the safety of electric vehicles. The commonly adopted propagation inhibition methods mainly include adding heat insulation materials and enlarging battery spacing, which could cause problematic heat dissipation and lower the system energy density. Herein, an innovative battery thermal management system composed of non-uniform thermal conductivity phase change materials and assisted liquid cooling is proposed. Combining the phase change materials with high and low thermal conductivity balances heat transfer and heat insulation requirements. The cooling performance and the ability of thermal runaway propagation mitigation of the proposed schemes are numerically studied. The results show that the proposed strategy can meet the heat dissipation requirements under normal operation and control the thermal runaway in a safe range by transferring the heat generated from the battery thermal runaway in the set direction. The maximum battery temperature and the temperature difference are 38.1 °C and 2.1 °C, respectively, under 3C discharge. Under thermal runaway conditions, the strategy successful confines the thermal runaway propagation within the middle row. The maximum battery temperature in other rows can be controlled under the irreversible thermal runaway reaction temperature of 200 °C. Further study found that increased thermal conductivity benefits the battery heat dissipation and reduces the risk of thermal runaway. However, it propagates faster and broader once the thermal runaway is triggered. In comparison, the decrease of thermal conductivity is beneficial to the mitigation of propagation but may reduce the overall heat dissipation of the battery module. This study can provide a new way to solve the contradiction between battery temperature control and thermal runaway spread suppression. • An innovative strategy is proposed to mitigate thermal runaway propagation. • Non-uniform phase change materials with different thermal conductivity are adopted. • The thermal runaway generated heat can be limited to transfer in a specific direction. • A suitable combination of high and low thermal conductivity for PCM is necessary. • Temperature control and thermal runaway suppression can be achieved simultaneously. [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]

In this work, a composite cooling system including composite phase change material(CPCM) and liquid cooling is designed for battery pack, and the effects of coolant flow rate, battery spacing, thermal conductivity of CPCM, channel number of cooling plate on the safety performance of battery pack under thermal runaway propagation are studied. The results reveal that: (1)Coolant flow rate increase mainly delays the thermal runaway propagation on both sides of cooling plate. When the coolant flow rate is 0.029 m/s, the thermal runaway propagation time through the cooling plate is 32.9s, which is extended by 1.84 times than that at 0.009 m/s (2)Battery spacing increase delays thermal runaway propagation and changes the propagation path. (3)Thermal conductivity reduction of CPCM can significantly delay thermal runaway propagation, because the heat is concentrated in the periphery of the battery and is hard to transfer though CPCM and cooling plate. (4)Compared with other influence factors, channel number of cooling plate has less influence on the overall thermal runaway propagation time. When the channel number is between 5 and 1, the total thermal runaway time changes within 25.5s–27s. The conclusions in this work are helpful to design a safer thermal management system for lithium-ion battery packs. • A novel composite cooling strategy is designed for cylindrical battery pack. • Effects of different factors on the thermal safety of the battery pack are studied. • Thermal runaway propagation path and time of the battery pack are analyzed and obtained. [ABSTRACT FROM AUTHOR]

Overcharge is a common case of battery thermal abuse, which can accelerate the aging of battery and cause the attenuation of battery capacity. In extreme conditions, overcharge can generate a large amount of heat, leading to battery failure and thermal runaway. Therefore, it is necessary to take measures to improve the safety during the overcharge process. In this paper, phase change materials (PCMs) are used to mitigate the temperature of overcharged lithium-ion batteries (LIBs), which proves that PCMs can effectively reduce the battery surface temperature as well as the probability of thermal runaway. In order to identify the appropriate PCM on the thermal management of overcharged LIBs, PCMs with phase change temperatures (PCTs) of 37°C, 43°C, 58°C are used in the tests. The results show that the PCM-37 exhibits the best performance. In addition, different degrees of overcharge also bring different effects to the battery, while the applications of PCMs can well mitigate the sharp increase in temperature. The findings demonstrate the feasibility of PCMs on improving the thermal safety of overcharging LIBs and further provide guidance on the development of more efficient battery thermal management systems (BTMSs) where the overcharge usually occurs. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are frequently employed in electric vehicles for their high energy density and lengthy cycle life. However, efficient battery thermal management system (BTMS) is critical for ensuring the reliability, safety, and service life, as temperature greatly impacts their performance. The potential risks of battery fire and explosion under excessive temperatures necessitate the development of effective emergency management and technologies to maintain safe operation. Phase change material (PCM) which offers distinct advantages, including reasonable cost, low energy consumption, and excellent temperature uniformity, making it an attractive candidate for thermal management, has emerged as a promising solution for BTMS. This comprehensive review aims to shed light on PCM-based BTMS, and it is found that carbon-based additives are better than metal-based additives concerning density and stability, and the addition of polymers and nanomaterials can improve the structural stability and mechanical properties. However, the flammability of PCM exacerbates the fire risk and hazard of battery thermal runaway (TR), and this review also has a particular emphasis on enhancing PCM's flame retardant properties and exploring its applications in BTMS. Flame-retardant PCM can ensure the safety of LIB utilization process and has a promising application in suppressing TR. Moreover, there exists a prominent challenge of the comprehensive need for optimization of heat dissipation optimization and improvement of TR propagation suppression ability of PCM-based BTMS. Finally, the challenges and outlooks focus on the future PCM-based BTMS are disclosed, in the hope of bring new insights to building a synergistic BTMS. Graphic abstract [Display omitted] • Heat dissipation optimization and thermal runaway propagation suppression coordination. • Highly thermally conductive, non-leakage deformable, flame retardant PCM compared. • Feasibility to utilize PCM to prevent the propagation of thermal runaway proposed. • Insights into research gap and further development and of PCM provided. [ABSTRACT FROM AUTHOR]

In this work, a novel battery thermal management system (BTMS) integrated with thermoelectric coolers (TECs) and phase change materials (PCMs) is developed to ensure the temperature working environment of batteries, where a fin framework is adopted to enhance the heat transfer. By establishing a transient thermal-electric-fluid multi-physics field numerical model, the thermal performance of the BTMS is thoroughly examined in two cases. The findings demonstrate that increasing the TEC input current, fin length, and thickness is beneficial for reducing the maximum temperature and PCM liquid fraction. Nevertheless, although the increase in fin length can lower the temperature difference, the influence of fin thickness and TEC input current on the temperature difference is tiny. Based on the numerical findings, the optimal fin length and thickness of 7 mm and 3 mm are obtained. In this situation, when the TEC input current is 3 A, the maximum temperature, temperature difference, and PCM liquid fraction in Case 1 are 315.10 K, 2.39 K, and 0.002, respectively, and those are respectively 318.24 K, 3.60 K, and 0.181 in Case 2. The configuration of Case 1 outperforms that of Case 2, due to the fewer TECs and greater distance from the battery pack to the TEC within Case 2. When experiencing a higher battery discharge rate, the TEC input current should also be correspondingly increased to ensure the temperature performance of the battery. The relative findings contribute to new insights into battery thermal management. • A novel BTMS combined with thermoelectric coolers and phase change materials is proposed. • A transient thermal-electric-fluid multi-physical field numerical model for the BTMS is developed. • The fin length, thickness, and TEC input current are suggested at 7 mm, 3 mm, and 3A. • The proposed BTMS can ensure battery temperature performance at high discharge rates. [ABSTRACT FROM AUTHOR]

• Handled the battery thermal management of a novel helical channeled cylindrical Li-ion battery. • Tested the performance of nanofluid and hybrid nanoparticle-enhanced phase change material for BTMS. • Noticed that the cooling channel arrangement actively removes stored heat from PCM, and reduces PCM temperature. • Observed that the coolant circulation rate keeps the cell temperature below the safe range even with a lower circulation rate of 30 mL/min. Electric vehicles (EVs) have emerged as a viable alternative to Internal Combustion (IC) engine-powered vehicles, and efforts have been directed toward developing EVs that are more reliable and safer to operate. The safe working of EVs necessitates the use of an efficient battery cooling system. In this paper, cooling of cylindrical type Li-ion battery embedded with helical coolant channels is proposed. The effects of nanoparticles on removing heat from the battery cooling system have been investigated for four different nanoparticle concentrations: 0, 2, 5, and 10% of Al 2 O 3 in the base fluid. Two cases of base fluids are considered: phase change material kept in a concentric container surrounding battery volume and coolant water circulated through liquid channels attached to the outer walls of the PCM (phase change material) cylindrical container. This study presented the three configurations (i) base case PCM-WLC: battery cooling system with a cylindrical enclosure filled with RT-42 phase change material. (ii) base case nePCM-WLC: battery cooling system filled with nano-enhanced phase change material. (iii) nePCM-LC: battery cooling system with helical liquid channels and filled with nano-enhanced PCM. The nanofluid was circulated through the liquid passages connected to the PCM container. Results showed using the helical channels, the nePCM-LC arrangement efficiently removes accumulated heat from the phase change material and provides better battery cooling than straight rectangular channel-based BTMS (battery thermal management system). [ABSTRACT FROM AUTHOR]

• A novel hybrid battery thermal management is proposed. • The mathematical model is established and then validated by the experiments. • The effectiveness of the proposed management system is proved experimentally. • The space of the proposed system is optimized via the mathematical model. A novel hybrid battery thermal management system, combining air-forced convection with phase change material, is proposed. The effectiveness of the system is proved experimentally. The maximum temperature difference and the maximum temperature are controlled within the optimum range in the proposed thermal management system even though the dynamic charge/discharge current rate is 4 C rate. Meanwhile, the thermal performance is also compared under the passive and active strategy. The result shows that the thermal performance under the active mode is obviously superior to that under the passive mode. Comparing with the passive mode, the maximum temperature difference and the maximum temperature in the active mode are reduced 1.2 °C and 16 °C under 3 C rate, respectively. Moreover, the mathematical model, based on the three-dimension heat transfer model coupled with the electrochemical model, is carried out and then validated with experimental data. Taking advantage of the mathematical model, the space of designed structures is further optimized. [ABSTRACT FROM AUTHOR]

In this study, a hybrid liquid cold plate design containing Z-type parallel cooling channel and PCM/aluminum foam composite, in conjunction with a novel delayed cooling strategy, is proposed to provide a compact, lightweight, and energy efficient solution for battery thermal management systems (BTMSs). A total of nine different cold plate designs, including one baseline cold plate without PCM composite and eight hybrid cold plates containing PCM composite, are analyzed systematically to demonstrate the superior cooling performance of the proposed cooling design. Specifically, the average temperature of battery surface and total power consumption performance of each design are analyzed and compared at a battery discharging rate of 1C under both continuous and delayed cooling schemes. Subsequently, two selected designs with superior cooling performance as well as the baseline cold plate are further investigated to discuss the effectiveness of hybrid liquid cold plates for cooling batteries at high discharge rates. The results show that the optimum hybrid cold plate design, which only weighs half of the baseline cold plate, can provide more than 50% reduction in the total pumping power while achieving the same cooling performance (i.e., with the average battery temperature controlled within 40 °C) compared with the baseline cold plate at battery discharging rates of 1C, 2C and 3C. These results can potentially provide important guidance to the design of advanced cooling systems for lithium-ion batteries. • A compact and lightweight battery thermal management system is proposed. • A delayed cooling strategy is proposed and analyzed. • Cooling performances were compared between different designs numerically. • Optimum cooling system allows >50% reduction in power consumption and weight. [ABSTRACT FROM AUTHOR]

• A compact battery thermal management system with phase change material is proposed. • The practical application of PCM under fast charging conditions is considered. • Battery thermal model and PCM model were validated well with experimental data. • The improvement of cooling performance and energy consumption is proven. A compact battery thermal management system (BTMS) coupled with a phase change material (PCM) is proposed to improve its performance under fast charging conditions. A battery thermal model and two-phase PCM simulation model were developed and validated through experimental data, and a parametric study was conducted by changing the parameters of the PCM and operating conditions of the liquid cooling system. As a result, in the proposed system, the highest maximum temperature of the battery module was 38.4 °C and maximum temperature difference was 3.9 °C during the charge–discharge cycle, and both of these values were simultaneously maintained within the proper range. The aforementioned values were 13.2 °C and 10.8 °C lower than the corresponding values for the conventional liquid cooling method. In addition, through the optimal operating conditions, sufficient heat dissipation was achieved while shortening the operating time of the liquid cooling system by 12.4 % of the total time. Finally, the heat absorbed by the PCM was dissipated sufficiently during the cycle. Therefore, the proposed BTMS is not only effective in terms of its cooling performance but also sufficiently usable in the continuous cycle. [ABSTRACT FROM AUTHOR]

• A battery thermal management system that uses fins to enhance the combination of thermoelectric cooler and phase change material was established. • Compared the effects of four thicknesses of fins on the thermal management performance. • It was proved that adding fins is beneficial to improve the thermal management performance under three working conditions. • The influence of the input current on the cooling power and COP of TEC was analyzed. In this study, a hybrid active & passive BTMS(Battery Thermal Management System) that uses fins to enhance the combination of TEC(Thermoelectric Cooler) and PCM(Phase Change Material) is shown. The cold side of the TECs produces a cooling effect, which is used to cool the PCM and prevent it from melting completely in a short time, thereby extending the temperature control time. Fins are used to transfer the heat of the PCM to the cold side of the TECs, and effectively cool the batteries at high temperatures. The effects of different fin thicknesses (2 mm-8 mm) and different TEC input currents (1A-6A) on thermal management performance were analyzed by numerical simulation. The results show that the temperature control time was prolonged by 12% when the fins were increased from 2 mm to 8 mm, but the temperature difference increased by 13.7%. When the current changed from 1A to 6A, the temperature control time increased by 87.42%, but the temperature difference and COP became worse. Comprehensive analysis of temperature control time, temperature difference, COP, 4 mm fin thickness, and TEC input current of 3A were optimal for the model in this paper. [ABSTRACT FROM AUTHOR]

Phase change material (PCM) technology is an interesting method for battery thermal management, while the cooling behavior and cooling efficiency of PCM on prismatic lithium-ion batteries are unclear. In this work, a series of experiments are conducted to systematically investigate the cooling efficiency of PCM and the several detailed factors on the thermal management performance, such as the structure, phase change temperature and thickness of PCM. The results show that the PCM structure (sides of the battery surround by PCM) has an excellent heat dissipation efficiency at high discharge rate of 2C. Decreasing the phase change temperature is beneficial to enhance the cooling performance. Moreover, increasing the thickness of PCM enhances the cool performance, but the heat dissipation efficiency will decrease once the thickness exceeds the value of 25 mm, hence the selection of the PCM thickness is variable based on the heat dissipation capability and cooling efficiency. Furthermore, by investigating the cooling behavior of PCM during the cycle test, it is found that the PCM structure with 25 mm thickness can keep the maximum temperature of the battery under 55 °C in dynamic cycling. This work can provide experimental references for the thermal management system of prismatic batteries. • The thermal performance of large format lithium-ion battery during charge and discharge stages was experimentally studied. • Quantifying the heat dissipation capacity and heat dissipation efficiency of PCM in the battery thermal management. • The effects of phase change temperature and thickness of PCM on the thermal management system were analyzed. • The PCM module with 25 mm thickness has an excellent cooling performance in dynamic cycling. [ABSTRACT FROM AUTHOR]

l The critical thermal issues of lithium-ion batteries are introduced. l The design principles for batteries thermal management are presented. l The latest advances on battery thermal management systems are summarized. l Emerging technologies for next-generation power batteries are discussed. Replacing conventional gasoline-powered cars with electric vehicles (EVs) can reduce not only pollution emissions but also the dependence on fossil fuels. As the most widely used power source to propel EVs, lithium-ion batteries are highly sensitive to the operating temperatures, rendering battery thermal management indispensable to ensure their high performance, long cycle life and safe operation. In this review, we summarize the recent advances in thermal management for lithium-ion batteries. The critical thermal issues caused by high temperature, low temperature and temperature non-uniformity are firstly discussed. The design principles and the existing thermal management systems are then presented and elaborated extensively. Emerging technologies such as thermoelectric devices and internal heating methods for future battery thermal management are analyzed. We highlight that the combination of passive and active cooling/heating methods is promising to meet the stringent thermal requirements, particularly under dynamic conditions with drastic power fluctuations. Finally, the remaining challenges and perspectives of thermal management systems with high efficiency and durability are provided. This review offers comprehensive guidance on the design of advanced thermal management system for next-generation power batteries. [ABSTRACT FROM AUTHOR]

Battery Thermal Management System (BTMS) plays a significant role in determining the Electric vehicles (EVs) operating range and battery operating life cycle. Indeed, Phase Change Material (PCM) with outstanding characteristics like passive energy utilization to cool the battery, low cost, and effective operation seems to be an attractive option to be used for BTMS of EVs. However, opting for an exact PCM for the required application of the battery system depends completely on the thermal properties of PCM. Therefore, drawbacks and the advancement of PCM integrated BTMS compared to others should be scrutinized to have a comprehensive assessment on the PCM-integrated BTMS. The present review article majorly focuses on: i) - Advanced thermal properties of organic, inorganic, and eutectic PCM for integration with BTMS; ii) - Secondary assisted PCM cooling system for BTMS; iii) - Experimental development carried out with incorporation of composite PCM with BTMS; iv) - Economic comparative analysis on integrating PCM with EVs; v) - Critical analysis on environmental benefits of PCM based BTMS for EVs. In addition, the key outcomes of utilizing nanoparticle dispersed PCM into battery systems are highlighted. A separate section has been elaborated on the techniques used to overcome the drawbacks of thermal conductivity in PCMs. Finally, critical analysis and consolidation of experimentally hybridized and analyzed composite PCM for performance enhancement of batteries presented in the article would be a hot spot for future research work on EVs. [Display omitted] • Effects of PCM on battery thermal performance of EV are analyzed. • Nanoparticle dispersed PCM into battery systems are highlighted. • Nano-particles and metal fins structure is a viable option. • Economic and environmental benefits of PCM based EV are analyzed. [ABSTRACT FROM AUTHOR]

Power batteries are treated as heart of the electrical vehicles and they release huge amount of heat throughout both charging and discharging processes. Hence Battery Thermal Management System (BTMS) is designed in order to control maximum temperature rise within a battery pack and to maintain even temperature distribution among the cells for increasing life span, efficiency and safety of the batteries. With an enticing characteristic feature such as low parasitic power, low weight, uniform temperature distribution among cells, passive thermal management system namely Phase Change Material (PCM) is justified as an efficient BTMS in recent years. The current work begins with the introduction of Hybrid Thermal Management System combined with PCM for enhancing cooling performance of BTMS. In addition to that, some of the thermal conductivity enrichment techniques for PCM (i.e. the usage of thermal conductive particles, cellular foams, encapsulation) are summarized. Research studies which involves various key parameters such as cell spacing, mass of PCM, thickness of PCM, specific heat capacity and thermal conductivity influencing the performance of systems are reviewed. Eventually, the results of several studies on PCM cooling are proposed in the conclusion part based on analysis of previous works. • Battery thermal management system of PCM assisted liquid cooling provides uniform temperature distribution among the cells. • Addition of high thermal conductive particles into the PCM helps in enhancing thermal conductivity of PCM. • Metal foams have a continuous skeleton structure with large thermal conductivity, and high structural strength. • Addition of high thermal conductive particles into PCM,CPCM which incorporates porous foams to PCM exhibits more conductivity. [ABSTRACT FROM AUTHOR]

A combined thermal management system for lithium-ion battery, which conjugates the air cooling and phase change material (PCM) cooling, is proposed. Based on the three-dimensional flow and heat transfer models coupled with electrochemical reaction, the thermal performances of battery pack during the discharge-charge cycles with natural convection only, combined natural convection and PCM cooling, and combined forced convection and PCM cooling are investigated and compared. The results show that the maximum battery temperature with natural convection only exceeds the optimum temperature at 1C. The thermal performance of battery pack with combined forced convection and PCM is superior to that with combined natural convection and PCM, and the maximum temperature and maximum temperature difference are both controlled within the ideal range at 2C. For combined forced convection and PCM cooling, the recommended PCM thickness is 2 mm for application considering both cooling performance and cost. The phase change temperature of 35 °C is most advantageous to the proposed thermal management system at the ambient temperature of 26.5 °C, and the maximum temperature and maximum temperature difference can still fall within the optimal operation criteria even at the ambient temperature of 35 °C. [ABSTRACT FROM AUTHOR]

This paper investigates three different configurations of a hybrid battery thermal management system (BTMS) using phase change material (PCM) as passive and air coolant as active cooling system. The PCM surrounded the battery cell is encapsulated in three different vessel cross-sections as circular, rectangular, and hexagonal with equal volumes. Each of these BTMS consists of 12 Sony 18650 batteries with the same pack holder. The thermal management of the battery pack is examined in the course of different charging and discharging rates. Results reveal that the thermal performance of both hexagonal and circular PCM vessels show generally the same behavior. Utilization the latent heat as the passive coolant in the battery thermal management is the strong point, which results show that the circular PCM configuration is the best one. However, in the high rate of charging or discharging condition, the uniform air channel around the rectangular shape makes a more efficient cooling compared to the other arrangements. • Investigate on the hybrid active-passive battery thermal management system (BTMS) is the main objective. • Phase change material (PCM) as passive and air coolant as an active cooling system are considered. • A transient numerical study conducted on the three different PCM encapsulation shape. • Uniform shape of PCM encapsulation (circular shape) is the thermal efficient in the passive cooling. • Uniform air channel, rectangular shape of PCM encapsulation is thermal efficient in the active cooling. [ABSTRACT FROM AUTHOR]

• A novel Coupled PCM-liquid cooling system (CPLS) for Li-ion battery pack. • Design of CPLS is optimized for the thermal performance of battery pack. • Effectiveness of CPLS is verified by the designed experiments. • Controlling strategy for the velocity and inlet temperature of coolant. • Improved cooling performance and energy-saving at different ambient temperatures. In order to improve the working performance of the lithium-ion battery pack in continuous operation under different ambient temperatures, a coupled composite phase change material and liquid cooling thermal management system is proposed. The simulation for this system under a cycle that a 3C rate discharging and then a 0.5C charging was conducted, as well as comparison tests concerning factors such as cell-to-cell spacing, cell-to-tube distance, channel number and coolant velocity. Simulation results showed that the coupled system with suitable design exhibited good thermal performance at an ambient temperature of 30 °C, which kept the maximum surface temperature and the temperature difference of the battery pack at 41.1 °C and 4 °C at the end of 3C discharge. Then, the latent heat of phase change material was also recovered by the liquid cooling during the 0.5C charge. Specially designed experiments have also been conducted to verify the effectiveness and practicability of the proposed coupled system. Based on this system, a liquid cooling strategy was proposed for controlling the velocity and inlet temperature of coolant by monitoring the temperature of the phase change material and environment. This further improved the thermal performance of the battery pack during cycling at different ambient temperatures and significantly reduced the unnecessary power consumption of liquid cooling during this process. [ABSTRACT FROM AUTHOR]

• Novel fin structures are proposed for heat transfer enhancement of PCM. • Visualization of the melting process of PCM within the BTMS is presented. • Thermal management performance of PCM-Fin based BTMS is evaluated. Phase change materials (PCM) based battery thermal management system (BTMS) usually suffers from the low thermal conductivity of PCM. In this paper, novel fin structures which consist of longitudinal fins and cylindrical rings are proposed for heat transfer enhancement. Experiments are firstly designed to compare the thermal performance of different BTMSs. Results demonstrate that the PCM-Fin system shows superior performance over the pure battery system and the PCM system. Numerical simulations are also conducted based on the model validation with the experimental data to reveal the underlying mechanisms. It is found that fin structures not only increase the heat transfer area but also introduce a thermal conductive network within the PCM, which contributes positively to the improvement of thermal performance of the battery. Moreover, the effects of the position of rings, the number of rings and fins, and the heat generation rate on the thermal management performance are evaluated. Results show that the optimal numbers for rings and fins are 1 and 8, respectively, and the recommended dimensionless distance between ring and battery is 0.2. It is also found that the PCM-Fin system can control the temperature rise of the battery even under the heat generation rate of 20 W. [ABSTRACT FROM AUTHOR]