EARLY DETECTION AND MANAGEMENT OF THERMAL RUNAWAY IN BATTERIES USING WATER MIST FOR AIR PRECOOLING

Abstract

In the present study, the use of air, precooled with a water mist for management of thermal runaway of a lithium ion cell is studied. A lumped capacitance model of the battery based on ordinary differential equations representing thermal transport and chemical kinetics of a 18,650 NCA/graphite cell based on Arrhenius electrochemical equations is used to simulate the thermal behavior, and an efficiency factor is used to account for the venting of the cell. An Eulerian approach is used for the evaporation of water mist. Both convective and radiative heat transfer are considered for modeling the heat transfer for the lithium cell. For convective heat transfer, flow across a cylinder is considered for maximizing heat transfer. Additionally, two basic methods of triggering mist precooling based upon the temperature of the battery and solid electrolyte interphase degradation were tested. Based upon the results, a conclusion was drawn that mist precooling triggered using temperature as a parameter can be an effective method to control thermal runaway.