Abstract A cell of a high energy density secondary battery, such as one having zinc and chlorine-on-carbon electrodes and a separator dividing the cell electrolyte portion into a smaller flow zone adjacent to the zinc electrolyte and a larger flow zone adjacent the chlorine-on-carbon electrolyte, includes a common outlet from both cell portions of such a structure that the flow of electrolyte through the larger cell zone helps to determine the rate of flow through the smaller zone. In preferred embodiments of the apparatus the same electrolyte is circulated to both zones by a single pump or driving means, the flow in the smaller zone is such as to cause a desirable circulation of electrolyte therein at a low speed which is still sufficient to prevent polarization at the zinc electrode and pitting and dendritic formations on it, and the rate of flow through such lesser flow zone is regulated by having the outlet from such zone communicate with a restricted portion of a Venturi or equivalent orifice in the main flow zone outlet passage.
A cell according to claim 1 wherein the separator is a synthetic organic polymeric plastic membrane and the sizes of the second inlet and outlet passageways are such as to maintain from 2 percent to 10 percent of the flow of the electrolyte through the cell passing through the anolyte sub-zone of the cell.
Claim 2
Independent Claim
140 words
A method of passing a small proportion of flowing electrolyte over an electrode of a cell of a high energy density secondary battery having a pair of electrodes and a separator in an electrolyte zone between them, dividing such zone into greater and lesser electrolyte flow sub-zones, during charging and discharging of such battery, which comprises flowing electrolyte to both electrolyte sub-zones of the cell, flowing the electrolyte passing through said sub-zones out of the cell through a common outlet, with the flow rate of electrolyte through the greater flow sub-zone controlling the flow through the lesser flow sub-zone by changing the pressure differential between the lesser flow sub-zone inlet and outlet, such changing increasing the differential and the rate of flow through the lesser flow sub-zone directly with increases in the rate of flow in the greater flow sub-zone.
Claim 3
Dependent Claim
101 words
A method according to claim 3 wherein the electrolyte is aqueous zinc chloride solution which has dissolved chlorine therein during discharge of the cell, the electrode of the lesser flow sub-zone is zinc and that of the greater flow sub-zone is chlorine-on-carbon, the electrolyte flows through the zones are 2 to 25 percent and 75 to 98 percent and the flow through the lesser sub-zone is regulated by maintaining the pressure at the outlet therefrom equal to that of the electrolyte exiting from the greater flow sub-zone at the narrowest portion of a Venturi-type restriction in the greater flow sub-zone outlet.
Claim 4
Dependent Claim
73 words
A method according to claim 4 wherein the cross-sections of the sub-zones of electrolyte, in conjunction with the pressures on such electrolyte portions, are such as to provide from 2 to 10 percent of the flow of electrolyte in the cell through the smaller flow sub-zone so as to maintain a small but sufficient circulation of electrolyte past the zinc electrode to prevent polarization thereat and to prevent pitting and dendritic formations thereon.
Claim 5
Independent Claim
199 words
A method of passing a small proportion of electrolyte over an electrode of a cell of a high energy density secondary battery having a pair of electrodes and a separator in an electrolyte zone between them, dividing such zone into greater and lesser electrolyte flow sub-zones, during charging of such battery, which comprises flowing electrolyte saturated with gaseous chlorine to the greater electrolyte flow sub-zone, between the separator and a chlorine-on-carbon electrode, and electrolyte containing no elemental chlorine or a lesser proportion thereof into and through the lesser electrolyte sub-zone between the separator and a zinc electrode, flowing the electrolytes passing through said sub-zones out of the cell through a common outlet, with the flow rate of electrolyte through the greater flow sub-zone controlling the flow rate through the lesser flow sub-zone and changing the pressure differential between the lesser flow sub-zone inlet and outlet, such changing increasing the differential and the rate of flow through the lesser flow sub-zone directly with an increase in the rate of flow in the greater flow sub-zone, and correspondingly, decreasing the differential and the rate of flow through the lesser flOw sub-zone when the flow rate in the other sub-zone is decreased.