Numerical study of a novel jet-grid approach for Li-ion batteries cooling

Abstract

Climate change is driving new and more efficient ways of producing and storing energy. In particular, Lithium-ion batteries demonstrate to be a worthwhile storage system for their high specific power and energy density. Due to electrochemical processes inside batteries, high temperatures are achieved during fast charge and discharge. Herein, a novel jet-grid cooling technique, named ImpFilm, featuring fluid impingement and fluid film is proposed. The idea is to introduce an innovative system able to guarantee stable and uniform temperature for Lithium-ion batteries with the purpose to reduce weight and costs. Firstly, the system has been designed by means of a preliminary 0D thermodynamic analysis. Then, 3D CFD simulations have been run on a single module to test its feasibility and effectiveness by the standpoint of fluid and thermodynamics. Mass flow rate, velocity field, volume fraction and temperature distribution are analyzed in the module by focusing on the impact of the geometry grid on both flow dynamics and cell temperature evolution. Results show that a parametric study on the grid design is necessary to balance the flow rate subdivision and to uniform the temperature of all the batteries. Eventually, new grid features prove to be effective in keeping battery temperature uniform and below hazardous thresholds.