Evaluating nanofluid-cooled hybrid Lithium-ion battery thermal management system under abnormal operating scenarios

Abstract

Hybrid cooling has become an emerging option for Li-ion batteries, especially for high C-rating. However, it is crucial to study the battery thermal behavior under various abnormal operating scenarios in real applications, but it has not been studied comprehensively. Hence, this study comprehensively assesses the thermal behavior (maximum temperature and temperature difference) of a hybrid battery thermal management system incorporating metal foam + phase change material composite pack integrated with wavy microchannels utilizing hybrid nanofluids under various abnormal situations (extreme ambient temperature, pump failure, high coolant inlet temperature and short circuit) for different discharge rates. The results show that hybrid cooling is necessary primarily for high discharge rates (≥4C). The primary factor influencing the maximum temperature is the discharge rate rather than the ambient temperature. At high coolant inlet temperature (higher than 313 K), the liquid circulation should be halted. Higher external short circuit resistance (higher than 0.8 Ω) reduces the heat generation but prolongs cutoff time, leading to maximum temperature exceeding the safe limit of 313 K. Early short-circuit events exceed the safe limit (within 1 s), while delayed short-circuit events remain within them. This highlights the need of maximum cutoff temperature criteria also for safe operation in abnormal situations. © 2024 Elsevier B.V.