The thermal pre-treatment of lithium-ion batteries (LIBs) combines the process steps of discharging, dismantling, and separating black mass from metallic components into a single process. This method is intended to serve as an initial step in the LIB recycling chain, aiming to enhance the efficiency of downstream recycling processes, including pyro-, hydro-, and bio-metallurgy. The process involves exposing LIB cells to moderate temperatures (below 300 °C) to trigger thermal runaway. To study this process, both experimental and numerical approaches are being employed, with the goal of better understanding the physico-chemical phenomena involved and providing insights for industrial optimization. The proposed numerical model uses a CFD-DEM framework, where Computational Fluid Dynamics (CFD) simulates the gas phase and the Discrete Element Method (DEM) models the solid battery phase. The simulations are conducted using the open-source software OpenFOAMⓇ, LIGGGHTSⓇ, and CFDEMcouplingⓇ. Experimental results have shown that the maximum temperature and release of chemical species vary with the battery’s state of charge (SOC). Four different battery types at four SOC levels are being analyzed. Based on the experimental data, a numerical model for a single particle was developed within the DEM framework, showing good agreement with the experimental results. This model is currently being tested with multiple particles to assess its scalability and relevance for industrial applications.