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With the development of fast charging unit for electric vehicles (EVs) battery, it is required to develop a battery pack that can maintain the temperature in the desired range. Hence, some thermal management system is required to enhance performance and safety issues. The objective of the present work is to enhance the performance of phase change material (PCM)‐based battery thermal management system (BTMS) for continuous charging/discharging cycles. The cycle is considered as 3C‐1C as charging‐discharging rates. The PCM‐in‐pack BTMS is effective only for one cycle, and after that, the value of maximum battery temperature (Tmax) and maximum battery temperature difference (ΔTmax) reaches above 60°C and 5°C, respectively. The PCM‐around‐cell BTMS (PCM layer around battery cells) is found effective in maintaining ΔTmax below 5°C for three consecutive cycles but found effective in maintaining Tmax below 60°C for the first cycle only. For further improvement, fins are utilized, and found that fin and PCM‐around‐cell BTMS can effectively maintain Tmax below 60°C for two cycles. Even the addition of fins is found effective after the second cycle; therefore, rest time between charging and discharging is explored for further improvement. With a 10‐min rest time, both Tmax and ΔTmax are found under 60°C and 5°C for four consecutive cycles. However, the value of Tmax increases around 4°C to 5°C after each cycle. This problem of increment in Tmax after each cycle is eliminated by 20‐min rest time and found almost similar Tmax for four consecutive cycles. For 20 min of rest time between charging and discharging, Tmax is found with PCM‐around‐cell with fin based BTMS as 44.98°C, 45.98°C, 46.49°C, and 46.82°C during four consecutive cycles. Hence, PCM‐around‐cell arrangement, fins, and rest time of 20 min can provide desirable results for a large number of consecutive cycles. [ABSTRACT FROM AUTHOR]

The era of electric mobility has started, and petrol/diesel vehicles are being replaced by electric vehicles (EVs). The phase change material (PCM) is a trending field of research in its application of energy storage and thermal management. PCM-based thermal management method is found to be quite simple and effective for battery packs. However, its commercialization is difficult due to its low thermal conductivity and extra weight addition to the battery pack. Hence, the present research focuses on the battery performance with PCM. The experimental setup for a 48V, 25Ah battery pack is developed, and its performance is explored with and without PCM. The numerical model for same sized battery pack is developed, and validated with experimental results. The major objective of the present research is to find the optimal gap between two battery cells so that a sufficient amount of PCM can be filled inside the battery pack. Initially, inline and staggered cell arrangements are examined, and no significant difference in thermal performance is found. Further, cell spacing of 5 mm, 3 mm, and 1 mm are examined, and maximum temperature and temperature difference are compared along with the weight and volume of the battery pack. For a single charging process, 1 mm cell spacing is found sufficient, considering the weight of the battery pack and thermal performance. However, with 1 mm cell spacing, temperature increases significantly after each charging and discharging. At the same time, 3 mm and 5 mm are found as feasible solutions considering single and double charging-discharging cycles, respectively. 3 mm cell spacing is better option when weight is a critical issue, while 5 mm cell spacing is better when thermal performance is a critical issue. The current study offers guidance in the advancement of battery packs, particularly in cases where space constraints are a concern. • The research focuses on utilization of optimal amount of PCM. • The battery charging experiments are carried out on 48V, 25Ah battery pack. • PCM OM42 reduced battery temperature by 18 %. • The inline and staggered arrangements are found equally effective. • 3 mm cell spacing is found sufficient with limited weight increment. [ABSTRACT FROM AUTHOR]