wet-proof gas-supply layer, for example made of Teflon and  acetylene black, a metal screen current collector and an  active carbon layer.  The type of metal used for the current collector may be  chosen based on its chemical stability in the cell, specifically 5  its stability in contact with the aqueous catholyte. In specific  embodiments the metal screen current collector may be  composed of stainless steel, nickel copper, titanium or alloys  thereof.  One or more electrocatalysts may be used. In some  embodiments a single electrocatalyst is used which is  capable of facilitating both the oxygen evolution reaction  (OER) on charge and the oxygen reduction reaction (OER)  on discharge. In other embodiments two or more catalysts  are incorporated in the cathode. A first electrocatalyst mate› rial for catalyzing the OER and stable down to, and prefer› ably beyond, the potential at which ORR takes place; and a  second electrocatalyst for catalyzing the ORR and stable up  to, and preferably beyond, the potential at which OER takes  place.  The active carbon layer may contain the electrocatalyst or  may be uncatalyzed. One particularly suitable electrocata› lyst that may be used to catalyze one or both of the OER or  ORR is iridium oxide compounds including compositionally  pure iridium oxide and solid solution compounds thereof.  Air cathodes suitable for use herein are described in detail  elsewhere. In particular U.S. Pat. Nos. 7,645,543; 7,282,  295; and U.S Patent Publication No.: US 2009/0311596 all  of which are hereby incorporated by reference in their  entirety, and in particular for their description of air cathode  structure and composition.  Itemized Specific Embodiments  The following is an itemization of some specific embodi› ments of the invention:  1. An alkali metal/oxygen electrochemical energy storage 35  cell, the cell comprising:  an anode comprising an alkali metal electroactive compo› nent material;  a cathode on or at which molecular oxygen is electro› reduced during cell discharge, the  a catholyte comprising water and one or more evaporative› loss resistant and/or polyprotic active compounds dis› solved in water that partake in a cell discharge reaction  and effectuate cathode capacity for discharge in the acidic  region, the catholyte in contact with said cathode; and  a protective membrane architecture interposed between the  cathode and the anode, the protective membrane archi› tecture having a first and second major surface, the first  surface adjacent to the cathode and in contact with the  catholyte and the second surface adjacent to the anode;  cathode in alkali metal ion communication with the anode;  and  wherein the protective membrane architecture solely  allows through transport of the alkali metal ion and prevents  liquids from contacting the alkali metal anode.  2. The cell of item 1, wherein the catholyte comprises:  water; and  a carboxylic acid dissolved in water, the acid represented by  the following general formula  R3  0  I  //  R 2 -c-c  I  \  RI  OH  US 9,660,311 B2  36  35  wherein R 1  represents an organic radical;  wherein R 2  represents H or an organic radical; and  wherein R 3  represents H or an organic radical.  3. The cell of item 2, wherein at least one of the organic  radicals represented by R  1 , R  $^{2 }$or R$^{3 }$comprises a carboxyl  group.  4. The cell of item 3, wherein the carboxylic acid is malonic  acid, thus R 2  and R 3  represent H and R 1  represents a  carboxyl group.  5. The cell of item 2, wherein at least one ofR1, R 2  and R 3  represents an organic radical selected from the group  consisting of an optionally substituted C$_{1 }$-C$_{10 }$alkyl group,  optionally substituted C$_{2}$-C$_{10 }$ alkenyl group, optionally  substituted C$_{2}$-C$_{10 }$alkynyl group.  6. The cell of item 2, wherein at least one ofR1, R 2  and R 3  represents an organic radical selected from the group  consisting of an optionally substituted C$_{4}$ -C$_{10 }$cycloalkyl,  optionally substituted C$_{4}$-C$_{10 }$ cycloalkenyl, and option› ally substituted 3-10 membered heterocyclyl.  7. The cell of item 2, wherein at least one ofR1, R 2  and R 3  represent an organic radical selected from the group  consisting of an optionally substituted carbo- and hetero› cyclic 5-10 membered aryl.  8. The cell of item 2, wherein the carboxylic acid is selected  from the group consisting of malonic acid, glutaric acid,  and methylsuccinic acid.  9. The cell of item 2, wherein the equivalent weight of the  acid that partakes in the cell discharge reaction, is selected  from the range of values consisting of 50-70 g/equivalent  of H+; 71-90 g/equivalent of H+; 91-110 g/equivalent of  H+.  10. The cell of item 2, wherein the concentration of the  carboxylic acid in the catholyte is greater than 1 molar.  11. The cell of item 2, wherein the concentration of the  carboxylic acid in the catholyte is 0.5 molar or greater.  12. The cell of item 2, wherein the concentration of the  carboxylic acid in the catholyte is 0.25 molar or greater.  13. The cell of item 2, wherein the concentration of the  carboxylic acid in the catholyte is between 0.05 molar and  1 molar.  14. The cell of item 2, wherein the catholyte further com› prises solid phase carboxylic acid in contact with its  solution.  15. The cell of item 2, wherein the catholyte is saturated with  the carboxylic acid.  16. The cell of item 2, wherein the carboxylic acid is malonic  acid.  17. The cell of item 16, wherein the concentration of  malonic acid in the catholyte is selected from the molar  range consisting of 0.5 molar to 2 molar, 2 molar to 4  molar, and greater than 4 molar.  18. The cell of item 2, further comprising a lithium salt  dissolved in water.  19. The cell of items 18, wherein the lithium salt is selected  from the group consisting of lithium nitrate, lithium  sulfate, and lithium perchlorate.  20. The cell of item 18, wherein the lithium salt is lithium  nitrate.  21. The cell of item 18, wherein the concentration of the  lithium salt in the catholyte is selected from the molar  range consisting of 0.5 molar to 1 molar, 1 molar to 2  molar, and greater than 2 molar.  22. The cell of item 20, wherein the carboxylic acid is  malonic acid and the concentration of malonic acid in the  catholyte is about 2 molar or about 4 molar or therebe› tween, and further wherein the concentration of the  lithium nitrate salt is about 2 molar. 