Method and apparatus for reducing water loss
An electrochemical cell is provided. The cell may include at least one anode; at least one cathode; and an electrolyte composition contacting the anode and the cathode. The electrolyte composition may include an alkali and a hydrophilic additive having one or more functional groups effective for bonding with water.
1 . An electrochemical cell, comprising:
at least one anode;
at least one cathode; and
an electrolyte composition contacting the anode and cathode, the electrolyte composition comprising an alkali and a hydrophilic additive.
2 . The electrochemical cell of claim 1 , wherein the electrolyte composition comprises sodium polyacrylate.
3 . The electrochemical cell of claim 1 , wherein the hydrophilic additive has a molecular weight of about 3,000,000.
4 . The electrochemical cell of claim 1 , wherein the hydrophilic additive comprises one or more polytheylene oxide, carboxymethylcellulose, alcohols, or amines.
5 . The electrochemical cell of claim 1 , wherein the hydrophilic additive comprises one or more functional groups effective for bonding with water.
6 . The electrochemical cell of claim 1 , wherein the hydrophilic additive is present in the electrolyte in an amount in a range of from about 1 weight percent to about 95 weight percent.
7 . The electrochemical cell of claim 1 , wherein the electrolyte comprises an alkaline hydroxide.
8 . The electrochemical cell of claim 7 , wherein the electrolyte comprises potassium hydroxide.
9 . The electrochemical cell of claim 1 , wherein the electrochemical cell is a fuel cell.
10 . The electrochemical cell of claim 1 , wherein the electrochemical cell is a battery.
11 . A composition, comprising:
an electrolyte comprising water and an alkali; and
a hydrophilic additive.
12 . The composition as defined in claim 11 , wherein the alkali is potassium hydroxide; and, the hydrophilic additive comprises an alcohol or an amine, and has a molecular weight greater than 500,000.
13 . An electrochemical cell stack comprising two or more of the electrochemical cells of claim 1 .
14 . A method, comprising:
adding a hydrophilic additive to an aqueous electrolyte to form an electrolyte composition, wherein the hydrophilic additive has one or more functional groups effective for bonding with water; and
reducing water loss in an electrochemical cell comprising electrolyte composition.
15 . The method of claim 14 , wherein the hydrophilic additive is added in a concentration in a range of from about 2 weight percent to about 5 weight percent based on the weight of the electrolyte composition.
16 . The method of claim 14 , wherein the hydrophilic additive comprises one or more of polyacrylate, glycerin, polytheylene oxide, carboxymethylcellulose, alcohol, or amine.
17 . A method for stabilizing relative humidity in an electrochemical cell comprising water and an electrolyte, the method comprising:
adding a hydrophilic additive having one or more functional groups effective for bonding with water to the electrolyte.
18 . The method of claim 15 , wherein the hydrophilic additive comprises one or more of polyacrylate, glycerin, polytheylene oxide, carboxymethylcellulose, alcohol, or amine.
19 . The method of claim 16 , wherein the hydrophilic additive is added in a concentration in a range of from about 2 weight percent to about 5 weight percent based on the weight of the electrolyte composition.
20 . The method of claim 16 , wherein the relative humidity stability is maintained at less than 60 percent relative humidity.
21 . The method of claim 20 , wherein the relative humidity stability is maintained at about 55 percent relative humidity.