The recent evolution of Lithium-Ion cells toward increasing energy-to-weight ratios makes them prone to critical events such as Thermal Runaway. Flammable and toxic gases are suddenly produced from the decomposition of internal components. To avoid an uncontrolled opening of the cell casing, the gases are vented out, which can potentially lead to fire. In this paper, six gaseous mixtures sampled experimentally, based on four different cathode materials are first compared for commonly observed 0D and 1D combustion processes. A single Analytically Reduced Chemistry scheme is derived for the six mixtures to lower computational cost and allow 3D high fidelity simulations. In comparison to the root detailed scheme, the reduced scheme offers low errors and an average speed up of 5.5 when computing targeted 1D flames, making it suitable for a 3D reactive Large Eddy Simulation of a burning so called “18650”-type cell. Such 3D simulations show a true potential to study simple safety design choices prior to any experimental investigation, reducing development costs. Under the same venting conditions, the number of venting holes is predicted to play a crucial role on flame intrinsic behavior.