Exploring the efficacy of using various coolants on lithium-ion 18650 cell employing conjugate heat transfer simulation

Abstract

Abstract In an era of depleting oil reserves, the turmoil of the energy crisis is getting worse every year. Adding to this the economic and political situations between crude oil-exporting nations are of major concern. Modification in internal combustion engines has reached limiting value, rendering them obsolete for future demands. Thus, Battery electric vehicles are the future of the automobile industry. Possessing advantages like zero-emission and high mechanical efficiency, the limitations of battery technology is hindering advancements in electric vehicles. Thermal management, charging time and energy density are major fields of research. Lithium-ion batteries, which are a core to this technology, exhibit poor performance beyond operating temperature ranges. An optimum working range is hence required. In order to study the cooling of the cell, Lithium-18650 cell is simulated for the different cooling conditions using SimScale™. A single cell is placed in a control volume and the fluid flow is set along the axis of the cell for the analysis. Heat is assumed to be generated at the centre of the cell. Parameters such as velocity (thus fluid discharge rate), current discharge (thus heat generated) are varied for each run of the simulation. Various coolant fluids viz. water, air, ethylene glycol, aluminium oxide in water nanofluid are used. Fluid velocity is varied as 0.01 m / s , 0.05 m / s , 0.5 m / s and 1 m / s . The current discharge is varied as 1C – 0.0896 W in 3600 s, 2C – 0.5248 W in 1800 s, 3C – 1.0284 W in 1200 s. Considering the various permutations of parameters, yields a total of 48 simulations, for four fluids, and are compared for the best combination of fluid and parameter governing cooling of the cell.