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Stokes-flow reversibility is violated in electrolyte solutions by a streaming-potential mechanism, where nonuniform convective currents within Debye layers surrounding charged particles induce electric fields in the electroneutral Ohmic bulk. We demonstrate the irreversibility consequences of this phenomenon for the problem of particle-pair sedimentation, where the two particles experience a repulsive force driven by bulk Maxwell stresses. At small separations the force scales inversely with the third power of separation distance. This singular behavior is associated with the counterrotation of the two torque-free particles, which leads through a lubrication mechanism to an intense electric field in the narrow gap between them. At large separations the force follows an inverse dependence upon the fourth power of separation, now associated with rectilinear particle motion.

We analyze one-dimensional charge conduction within an ionic solution in the presence of supporting electrolytes that do not discharge on the electrodes. For thin Debye layers, numerical simulations predict current abatement, in agreement with experimental knowledge; in addition, they reveal unconventional features absent from classical analyses of binary solutions, such as high cation concentration near the electrodes. We derive a companion asymptotic description of the problem in the singular thin-Debye-layer limit, reproducing these attributes. The asymptotic analysis reveals a nested boundary-layer structure about the reactive electrodes and furnishes a universal current-voltage relation.