Abstract: The invention features an electrochemical cell having two fluid-containing compartments separated by a non-selective microporous membrane. Select ions which would normally pass through the membrane under the influence of an ionic field, are prevented from passing through the membrane by a polyelectrolyte which has migrated through the compartment fluid to the membrane. The polyelectrolyte acts as an ionic barrier to the passage of select ions, thus effectively increasing the ion-selective capability of the membrane and, hence, the coulombic efficiency of the electro-chemical cell.

Abstract: An electrochemical cell construction features a novel co-extruded plastic electrode in an interleaved construction with a novel integral separator-spacer. Also featured is a leak and impact resistant construction for preventing the spill of corrosive materials in the event of rupture.

Abstract: Shunt currents can be eliminated in electrochemical devices by introducing nulling currents via auxiliary electrodes. The invention teaches the reduction or elimination of these shunt currents in such devices with minimized power consumption. Shunt current nulling tunnels are provided which interconnect with electrolyte supply channels feeding the cells of the electrochemical device. Power consumption for the shunt current-nulling tunnels is reduced by designing the tunnels to have an increasing electrical resistance towards their mid-portions. Another embodiment of the invention features an increasing electrical resistance towards the mid-portion of the tunnels and a decreasing electrical resistance towards the mid-portion of the manifolds.

Abstract: Shunt currents can be eliminated in electrochemical devices by introducing nulling currents via auxilary electrodes. In electrochemical devices including those having a circulating electrolyte, such electrodes are designed to have a generally annular shape in order to provide a substantially uniform current density profile along a common electrolyte carrying manifold. The uniform current density profile allows for the elimination of these harmful shunt currents with a minimum of power consumption.

Abstract: Shunt currents can be eliminated in electrochemical devices by introducing nulling currents via auxiliary electrodes. In electrochemical devices including those having a circulating electrolyte, such electrodes are designed to have a generally annular shape in order to provide a substantially uniform current density profile along a common electrolyte carrying manifold. The uniform current density profile allows for the elimination of these harmful shunt currents with a minimum of power consumption.

Abstract: The invention features an electrochemical cell having two fluid-containing compartments separated by a nonselective microporous membrane. Select ions which would normally pass through the membrane under the influence of an ionic field, are prevented from passing through the membrane by a polyelectrolyte which has migrated through the compartment fluid to the membrane. The polyelectrolyte acts as an ionic barrier to the passage of select ions, thus effectively increasing the ion-selective capability of the membrane and, hence, the coulombic efficiency of the electrochemical cell.

Abstract: The present invention is directed to a method of minimizing shunt currents in electrochemical devices which have a plurality of cells connected, at least in part, in series and which have an electrolyte which is a common electrolyte to at least two of the cells and which includes shared electrolyte, whereby an electrical electrolytic conductive bypass path is created around such cells and through said shared electrolyte, resulting in undesirable shunt currents. The method involves applying a protective current through at least a portion of said conductive bypass path through said shared electrolyte in a direction which is the same as the shunt current through said shared electrolyte and of a magnitude which effectively at least reduces said shunt currents. Thus, a single protective current is applied in series with at least a portion of the conductive bypass path such that shunt currents are minimized, and preferably are totally eliminated.