Therefore, this note aims to discuss and clarify the practical aspects of using MD simulations to calculate the glass transition temperature (T g ). Here we delve into the intricacies of setting up MD simulations, choosing the two different methods of annealing simulations, and analysing the results in order to extract (T g ). By surveying the literature and assessing computational protocols, we show how one can determine (T g ) of polymer electrolyte using MD simulations by taking the PEO/LiTFSI (poly(ethylene oxide)/lithium bis(trifluoromethane)sulfonimide) system as an example.