Investigation of the heat generation characteristics of lithium-ion battery and orthogonal analysis of its constructal cold plate structure parameters

Abstract

In this paper, we combine NTGK with flow and heat transfer model to perform numerical calculations on battery and cold plate to investigate thermal characteristics of li-ion batteries cooled by liquid and performance of cold plate during entire discharge process. A battery heat generation model is created using Kriging method after impacts of ambient temperature, SOC, and discharge rate are examined. Additionally, a new sort of cold plate is suggested based on constructal-theory, which performs better than conventional cold plate. Constructal cold plate reduces time needed for battery average temperature and maximum temperature differential to 25 °C and 5 °C by 15.25 % and 10.58 % for TimeT and TimeΔT, respectively, and pressure drop Δp by 22.89 % when compared to straight channel cold plate. Cooling effect of constructal cold plate is marginally inferior to that of serpentine cold plate, but flow resistance is greatly decreased, and pressure drop is only about one-tenth that of serpentine cold plate. Performance of constructal cold plate was examined using orthogonal optimization to determine effects of width of inlet and outlet and length of major channels. TimeT, TimeΔT, and Δp are decreased by 11 %, 14.69 %, and 15.22 % after optimization, and comprehensive performance is nearly doubled with improved performance.