Structural modifications of sinusoidal wavy minichannels cold plates applied in liquid cooling of lithium-ion batteries

Abstract

In this article, novel configurations of wavy minichannels with both co- and counter-current operation modes are proposed for the thermal management of lithium-ion battery systems, and their performance is investigated by incorporating a 3D conjugative numerical model and an experimental test validation. The structure of each case is specified by variable wavelengths along the flow direction. Three criteria of heat transfer enhancements, temperature uniformity improvements, and flow resistance augmentations are considered to analyze the thermal and hydraulic characteristics of the nonuniform wavy minichannels. The results show that although the Nusselt number of the nonuniform cases is higher than that of the conventional ones (more than15%), they require higher friction factors (between 25.3 % and 93.6 %) to access such Nusselt numbers. At the studied range, a maximum Nu enhancement of 1.18 and a maximum f augmentation of 1.93 are recorded. It is found that the current operation mode is a key factor affecting the temperature uniformity degree. By increasing the coolant velocity from 0.106 to 0.951 m s−1 in the co-current mode, the temperature non-uniformity decreases from 14.79 to 1.10 K, while this range for the counter-current mode is from 6.73 to 0.43 K. It is also found that for a special design of the nonuniform wavy minichannels, the deviations of the temperature non-uniformity at the entire range of the coolant velocity are <0.7 K.