  Silicon (Si) anodes attract a lot of research attention for their potential
to enable high energy density lithium-ion batteries (LIBs). Many studies focus
on nanostructured Si anodes to counteract deterioration. In this work, we model
LIBs with Si nanowire (NW) anodes in combination with an ionic liquid (IL)
electrolyte. On the anode side, we allow for elastic deformations to reflect
the large volumetric changes of Si. With physics-based continuum modeling we
can provide insight into usually hardly accessible quantities like the stress
distribution in the active material. For the IL electrolyte, our
thermodynamically consistent transport theory includes convection as relevant
transport mechanism. We present our volume-averaged 1d+1d framework and perform
parameter studies to investigate the influence of the Si anode morphology on
the cell performance. Our findings highlight the importance of incorporating
the volumetric expansion of Si in physics-based simulations. Even for
nanostructured anodes - which are said to be beneficial concerning the stresses
- the expansion influences the achievable capacity of the cell. Accounting for
enough pore space is important for efficient active material usage.
