Thermal management of lithium-ion batteries using carbon-based nanofluid flowing through different flow channel configurations

In this study, a novel lithium-ion battery (LIB) thermal management system is developed, and its cooling performance for cylindrical 18,650 LIB cells under different discharging rates is experimentally observed. The experiments are carried out using indirect-type liquid cooling with single and dual aluminium serpentine channels with different flow configurations. The study includes the preparation of nanofluid using multi-walled carbon nanotubes (MWCNTs) at three different volume fractions (V_f) (0.15%, 0.3%, and 0.45%) in the mixture of ethylene glycol and water and compares their cooling performance with water and ethylene glycol-water mixture. At 0.45% V_f of MWCNTs, the maximum drop in the average temperature of the battery cells is observed about 6.9 °C, 10.2 °C, and 11 °C at 2.1C in a single-channel flow configuration, dual-channel with parallel flow configuration, and dual-channel with counter-flow configuration, respectively. Dual-channel with counter-flow configuration provides the best cooling performance in terms of temperature drops of 8.6–13 °C using different working fluids. When a counter-flow configuration is used, the battery module's temperature uniformity is very good, with a maximum deviation of 1.5–3 °C, well within the safe limit to prevent thermal runaway. The pressure drop for 0.45% V_f of MWCNTs is 13.3% and 14% higher than water for single-channel and dual-channel, respectively.