In a recent perspective article in the Journal of the Electrochemical Society, Scott Roberts, in collaboration with the research group of Prof. Venkat Subramanian at the University of Texas, Austin, discussed how proper formulation of boundary conditions for moving boundary problems (such as growth of dendrites on lithium during cycling) is paramount to ensuring mass conservation and therefore proper interpretation of simulation results. DOI: 10.1149/1945-7111/ac2091