  Diffusion-driven processes are important phenomena of materials science in
the field of energy conversion and transmission. During the conversion from
chemical energy to electrical energy, the species diffusion is generally linked
to the rate of exchange, and hence to the performance of the conversion device.
Alternatively, the transmission of the electric field diffuses the species when
it passes through any medium. The consequences of this effect can be regulated
to attune surface nano-patterns. Otherwise, uncontrolled morphologies may lead
to permanent degradation of the metallic conductors. Therefore, the
understanding of the material behavior, in the presence of the driving forces
of the diffusional species, is of scientific interest. The presented
dissertation proposes to investigate one example of species diffusion in each
case, during energy conversion and transmission. Specifically, the objective of
the study is to explore the lithium insertion into the cathode electrode of
lithium-ion batteries and the morphological evolution of inclusions, while
propagating under the electromigration in the metallic conductors. The
presented dissertation demonstrates that the phase-field methods are able to
elegantly capture the essential physics of the diffusion-driven phenomena
discussed above.
