Estimation of Heat Flux From Gases Released During Thermal Runaway of Lithium-Ion Batteries

Abstract A jet is formed from venting gases of lithium-ion batteries during thermal runaway. Heat fluxes to surrounding surfaces from vented gases are calculated with simulations of an impinging jet in a narrow gap. Heat transfer correlations for the impinging jet are used as a point of reference. Three cases of different gap sizes and jet velocities are investigated and safety hazards are assessed. Local and global safety hazard issues are addressed based on average heat flux, average temperature, and average temperature rise in a cell. The Results show that about 40% to about 70% of venting gases energy can leave the module gap where it can be transferred to other modules or causes combustion at the end of the gap if suitable conditions are satisfied. This work shows that multiple vents are needed to increase the temperatures of the other modules’ cells to go into thermal runaway. This work is a preliminary assessment for future analysis that will consider heat transfer to the adjacent modules from multiple venting events.