Superlimiting Current

Electrophoresis of the second kind refers to the nonlinear electrokinetic motion of a conducting particle passing a superlimiting current due to electroosmotic flow of the second kind. 

Space charge refers to the extended diffuse charge in an electrical double layer, which is passing a superlimiting current. 

A superlimiting current in an electrolyte is an ionic current large enough to exceed diffusion limitation, which depletes the bulk salt concentration and leads to the formation of extended space charge. 

---