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Battery thermal management system (BTMS) is essential for maintaining batteries in electric vehicles at a uniform temperature. The aim of the present work is to propose most suitable cooling for BTMS. The most significant factors in battery thermal management are operating temperature, reliability, safety, and battery life cycle. The experimental setup is designed and fabricated for that purpose. In experimental work, thermal performance parameter, i.e. variation of maximum cell temperature in battery pack with natural and forced convection, is studied and compared at three different charging rates low (1 C), moderate (2 C), and high (3 C). The numerical model for natural and forced convection battery thermal management is developed using Ansys 22.1. For the present work, the cylindrical cell Li-ion battery pack is considered and simulates the cooling effect due to natural convection and forced convection. For the various flow rate of air, the cooling effect is investigated and efficient flow velocity is obtained by a numerical model for two climatic conditions. Further, the cooling performance of the battery pack with and without fin for optimum velocity is simulated. Based on experimentation, it is seen that forced convection gives better results as compared to natural convection. The temperature drops from 60.46 °C to 43.03 °C (28.82%) at 1 C, 65.81 °C to 48.01 °C at 2 C (27.06%), and 67.05 °C to 50.4 °C (24.77%) at 3 C heat generation rate when forced convection is used for cooling purpose. In the numerical studies, charging of Li-ion cell at 1.5 C rate is studied. Using forced convection maximum temperature is reduced by 27.26% when the inlet velocity is kept 2 m s−1 when ambient is 27 °C. Using fin, battery cell maximum temperature is reduced by 39.23%, as compared with natural convection. Using fin at 27 °C atmospheric temperature, battery cell maximum temperature is reduced by 39.23%, as compared with natural convection, and when the atmospheric temperature reaches to 41 °C, the maximum temperature is reduced to 51.26 °C (12.75%). [ABSTRACT FROM AUTHOR]

This study aims to improve the performance of automotive battery thermal management systems (BTMS) to achieve more efficient heat dissipation and thus reduce hazards during driving. Firstly, the research parameters and properties of composite thermally conductive silicone materials are introduced. Secondly, the heating principle of the power battery, the structure and working principle of the new energy vehicle battery, and the related thermal management scheme are discussed. Finally, the research results are presented from the experimental test and controller design. In addition, to achieve the research goal, the composite thermally conductive silica gel plate (CSGP) material is studied in detail and parametrically analyzed, and the heating mechanism of the power battery is discussed in depth. The temperature characteristics after adding CSGP are experimentally tested, and the controller of the BTMS of the new energy vehicle is designed, including hardware circuits and software modules. The findings show that the temperature characteristics of the battery module have obvious limitations without CSGP. When the battery module operates at a 4C magnification, the temperature exceeds the safety threshold by 38.4%, with particular potential safety risks. Then, the maximum temperature of the battery module with CSGP can be controlled within 50 °C, and the temperature characteristics are prominently improved. Lastly, the controller of the BTMS is tested, and the results reveal that it has remarkable voltage recovery ability. According to the research results, the performance of automotive BTMS can be significantly improved, and better heat dissipation can be effectively achieved by adding CSGP. This helps reduce the hazards of driving. Moreover, the designed controller performs well in voltage recovery, providing solid theoretical support for further developing the CSGP battery management system. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the feasibility of a novel dual-evaporator loop heat pipe (DE-LHP) in battery thermal management systems (BTMS). A 3S4P (3-series and 4-parallel) Li-ion battery module with a 12.6 V and 10 Ah capacity is made and tested under various C rates for different environmental conditions. The battery generates an average heat of 11.28 W@1C and 24.44 W@1.5C with 100% discharge and 43.36 W@2C with 50% discharge at an ambient temperature of 30 °C. An increase in temperature from 30 to 40 °C results in a decline in the depth of discharge. The proposed DE-LHP is evaluated using deionized water with filling volumes of 12, 16, 20, and 24 mL. The DE-LHP started working above 5 W regardless of the filling volume, and before the evaporator reached dry-out, the DE-LHP transferred heat loads of 10, 30, 35, and 55 W with filling volumes of 12, 16, 20, and 24 mL, respectively. At a heat load of 30 W, the evaporator section of the 20-mL filled LHP demonstrated a minimum thermal resistance of 0.274 KW-1, while the condenser section exhibited a minimum thermal resistance of 0.372 KW-1 at a heat load of 35 W. The DE-LHP is found to be effective in transferring heat of 35 W to keep the module temperature below 60 °C. Based on these initial findings, it is suggested that incorporating the multi-evaporator LHP-based BTMS could be a feasible and efficient solution for the thermal management of battery modules/packs for electric vehicles. [ABSTRACT FROM AUTHOR]

Modern commercial electric vehicles often have a liquid-based BTMS with excellent heat transfer efficiency and cooling or heating ability. Use of cooling plate has proved to be an effective approach. In the present study, we propose a novel liquid-cold plate employing a topological optimization design based on the globally convergent version of the method of moving asymptotes (GCMMA) method. Comparison with a traditional liquid-cold plate with straight cooling channels revealed that the topology-optimized configuration provides more uniform temperature distribution on the cold plate surface by reducing 48 % of the maximum temperature difference and 57 % of the temperature standard deviation for Q0 = 1255 W/m2. This shows that the topology optimization method is a useful and high-efficiency approach for the innovative design of liquid-cooling plates used for battery thermal management. [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]

With the extensive application of lithium batteries and the continuous improvements in battery management systems and other related technologies, the requirements for fast and accurate modeling of lithium batteries are gradually increasing. Temperature plays a vital role in the dynamics and transmission of electrochemical systems. The thermal effect must be considered in battery models. In this paper, a simulation model of a lithium battery with thermal characteristics is established. This thermal model is coupled with a temperature-dependent 2-RC equivalent circuit model to form an electro-thermal model for lithium-ion batteries. The hybrid pulse power characterization test is used to estimate the equivalent circuit parameters. Finally, under NEDC and DST conditions, battery voltage and temperature estimation results of the electro-thermal model are analyzed to verify the correctness and accuracy of the model. The voltage error is within − 0.16 ~ 0.20 V under the NEDC condition. Moreover, under the DST condition, the maximum relative error in the electro-thermal model is within 5%. [ABSTRACT FROM AUTHOR]