In this talk we will discuss interdisciplinary efforts on multiscale modeling of electrochemical devices undertaken at the Alliance for Computationally-guided Design of Energy Efficient Electronic Materials (CDE₃M). Specifically, we focus on our recent results in modeling components of Li-ion batteries, including solid electrolyte interphase (SEI), SEI/electrolyte interfaces, and nanostructured Si anodes. The coupling of electrochemical and mechanical processes inside electrodes and at electrode/SEI interfaces is one of the key challenges that has to be addressed in order to provide efficient materials-by-design of novel batteries. Most of the current modeling tools only consider these system at the continuum level. We have focused on the development of multiscale modeling tools that allow us to couple the atomic, molecular and nanoscale electrochemical and mechanical processes with continuum level modeling. In this talk we will discuss i) mechanisms of Li-ion transport through bulk SEI and SEI/electrolyte interfaces, ii) mechanical properties of SEI and its failure mechanism under large deformations, and iii) chemical/mechanical coupling during lithiation of nanostructured Si-based electrodes.