Thermal runaway and its propagation are major safety issues in containerized lithium-ion battery energy storage systems. While conduction-driven propagation has received much attention, the thermal hazards associated with propagation via hot gases vented from failing cells are still not fully understood. Vented gases can lead to global safety issues in containerized systems, via heat transfer to other parts of the system and potential combustion hazards. In this work, we validate the characteristics of vented gases from cells undergoing thermal runaway in the thermal propagation model LIM1TR (Lithium-ion Modeling with 1-D Thermal Runaway). In particular, we assess the evolution of vented gases, venting time, and temperature profiles of single cell and multi-cell arrays based on experiments performed in Archibald et al (Fire Technology, 2020). While several metrics for estimating the venting time are assessed, a metric based on the CO2 generation results in consistent predictions. Vented gas evolution, and venting times predicted by the simulations are consistent with those estimated during the experiments. The simulation resolution and other model parameters, especially the use of an intra-particle diffusion limiter, have a large role in prediction of venting time.