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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]

Efficient heat transfer control is highly demanded for dynamic thermal management of equipment and buildings especially when the environmental temperature dramatically changes. Thermal switches, the current approach of heat transfer control, suffer from the issues of low switching ratios below eight and sharp state transition between "on" and "off". Herein, a continuously‐tuned thermal regulator with an ultrahigh thermal‐conductivity change ratio of 43 based on superaligned carbon nanotube aerogel is reported, which works on the regulation of both thermal interfacial resistance and conduction pathways by compressive deformation‐induced microstructure evolution. This thermal regulator can stabilize the device temperature at 25 °C when the environmental temperature varies by 7 and 11 °C under the natural convection and forced convection conditions, respectively. Toward practical application, the thermal regulator with flexibility is wrapped around a cylindrical lithium‐ion battery to control the operation temperature within the optimal range of 20–40 °C for enhanced discharging performance even at an environmental temperature of −20 °C. Besides, by combining the thermal regulator with radiative cooling film, the house model temperature can be lowered by 2.7 °C during daytime and raised by 1.1 °C during nighttime compared with the bare one. This efficient thermal regulation approach offers an effective solution for practical thermal management. [ABSTRACT FROM AUTHOR]

Nickel chloride (NiCl2) is a typical hexagonal layered semiconductor material with wide application. However, it is mainly restricted by complicated technological process within ultrahigh dehydration temperature. Utilizing copper doping, a sort of high purity and remarkable crystallinity NiCl2 is fabricated using a simple low‐temperature calcination technique. The dehydration temperature is decreased from 600 to 400 °C because the adsorbed copper ions on NiCl2 dihydrate surface can weaken NiO bond strength. Serving for thermal battery cathode, copper‐doped NiCl2 exhibits remarkable discharge ability at 500 mA cm−2, equipped with supernormal power density of 16.27 kW kg−1 and energy density of 717 Wh kg−1 simultaneously. Its energy density is increased by 28% compared to NiCl2. Copper doping optimizes thermodynamics process of discharge reaction and modifies local electronic structure of NiCl2. For copper‐doped NiCl2, the shift of Ni 3d and Cl 3p to lower energy level results in elevated redox potential, and the reduction of bandgap accelerates the carrier mobility, further promoting discharge degree. Utilizing metal ions dopant, this research surmounts the low‐temperature synthesis of NiCl2 and addresses its inferior electrochemical performance, ensuring high energy‐power output. This will expand the application scenarios of NiCl2‐based cathode materials. [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]

Battery thermal management system (BTMS) may seem a very standard term, but it is the lifeline of an efficient battery pack module in various vehicles and standalone stationary energy storage systems. The majority of the available literature is aimed toward temperature optimization of batteries in hotter climatic conditions. The cold temperature‐related effects on battery packs have amplifying implications on the battery cycle life and operational capacity. The electric vehicles operating in cold temperature environment face sudden fluctuations in temperatures across the battery pack module due to large temperature gradient between battery surface and internals, and ambient conditions. This work focuses on addressing the problem related to sudden drop in cell temperatures when battery operations are switched off (cold stop conditions). The phase change materials (PCMs) based passive BTMS system is evaluated in this study. The BTMS with different designs and PCMs are modeled in Multiphysics environment and simulated close to extreme cold temperature environments. The formulated models are then used for comparing commercially available PCMs material for their efficiency and viability. The main parameter evaluated was rate of temperature decrease, it was observed that organic mixture‐type PCMs are best suited for cold temperature application. [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]