  The robust, scalable simulation of flowing electrochemical systems is
increasingly important due to the synergy between intermittent renewable energy
and electrochemical technologies such as energy storage and chemical
manufacturing. The high P\'eclet regime of many such applications prevents the
use of off-the-shelf discretization methods. In this work, we present a
high-order Discontinuous Galerkin scheme for the electroneutral Nernst-Planck
equations. The chosen charge conservation formulation allows for the specific
treatment of the different physics: upwinding for advection and migration, and
interior penalty for diffusion of ionic species as well the electric potential.
Similarly, the formulation enables different treatments in the preconditioner:
AMG for the potential blocks and ILU-based methods for the advection-dominated
concentration blocks. We evaluate the convergence rate of the discretization
scheme through numerical tests. Strong scaling results for two preconditioning
approaches are shown for a large 3D flow-plate reactor example.
