# US 2008/0187795 A1 · Use of an Electrochemical Cell Such as a Fuel Cell > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0187795 A1 - Document ID: US20080187795A1 - Status: Published application - Kind: A1 - Application number: 11/575,526 - Filed: 2005-09-21 - Published: 2008-08-07 - Earliest claimed: 2004-09-21 - Assignees: ITM Fuel Cells Ltd. - Inventors: Donald James Highgate; Simon Bourne; Steven David Scowcroft - Web page: https://patentgrep.com/patent/US20080187795A1 ## CPC - H01M 8/22: Fuel cells in which the fuel is based on materials comprising carbon or oxygen or hydrogen and other elements; Fuel cells in which the fuel is based on materials comprising only elements other than carbon, oxygen or hydrogen - H01M 8/0239: Organic resins; Organic polymers - H01M 8/0243: in the form of mixtures - H01M 8/04194: {Concentration measuring cells} - H01M 8/04447: {of anode reactants at the inlet or inside the fuel cell} - H01M 8/04455: {of cathode reactants at the inlet or inside the fuel cell} - H01M 8/04798: {of fuel cell reactants} - H01M 8/04805: {of fuel cell exhausts} - H01M 8/083: Alkaline fuel cells - H01M 8/1011: Direct alcohol fuel cells [DAFC], e.g. direct methanol fuel cells [DMFC] - H01M 8/1013: {Other direct alcohol fuel cells [DAFC]} - H01M 8/1018: Polymeric electrolyte materials - H01M 8/1044: Mixtures of polymers, of which at least one is ionically conductive - H01M 8/1062: characterised by the physical properties of the porous support, e.g. its porosity or thickness - H01M 8/1067: characterised by their physical properties, e.g. porosity, ionic conductivity or thickness - H01M 4/92: Metals of platinum group (H01M4/94 {, H01M4/9058} take precedence) - H01M 2008/1095: {Fuel cells with polymeric electrolytes} - Y02E 60/50: Fuel cells - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A method of performing an electrochemical reaction in an electrochemical cell comprises electrodes separated by a membrane capable of taking up an electrolyte, the method comprises introducing into the cell a fuel or other oxidisable component and an electrolyte, and oxidising the fuel in the presence of an acid or alkali. Alternatively or in addition, usage of fuel may be monitored by including a reactant that is capable of undergoing or imparting a change in visual appearance on oxidation or reduction; and monitoring any change in visual appearance. ## Claims ### Claim 1 A method of performing an electrochemical reaction in an electrochemical cell comprising electrodes separated by a membrane capable of taking up an electrolyte, the method comprising introducing into the cell an oxidisable component and an electrolyte, and oxidising the fuel in the presence of an acid or alkali. ### Claim 2 (depends on 1) The method according to claim 1, wherein the membrane is ionically inactive. ### Claim 3 (depends on 1) The method according to claim 1, wherein the membrane is of relatively low conductivity in the absence of the introduced components. ### Claim 4 (depends on 1) The method according to claim 1, wherein the ionic conductivity of the membrane is less than 60% of that of Nafion 117. ### Claim 5 (depends on 1) The method according to claim 1, wherein the oxidizing comprises introducing a liquid oxidant. ### Claim 6 (depends on 1) The method according to claim 1, wherein one of the oxidisable component and the oxidant includes an acid and the other includes an alkali. ### Claim 7 (depends on 1) The method according to claim 1, wherein the oxidisable component is a fuel that is an alcohol or a borohydride. ### Claim 8 (depends on 7) The method according to claim 7, wherein the fuel is methanol, ethanol or sodium borohydride. ### Claim 9 (depends on 1) The method according to claim 1, wherein the electrolyte is alkaline. ### Claim 10 (depends on 9) The method according to claim 9, wherein the electrolyte is sodium hydroxide or potassium hydroxide. ### Claim 11 (depends on 1) The method according to claim 1, wherein the cell is in the form of a membrane-electrode assembly (MEA) or a stack of MEAs. ### Claim 12 (depends on 1) The method according to claim 1, in which the membrane is a composite membrane of any combination of neutral and AE and CE materials. ### Claim 13 (depends on 1) The method according to claim 1, wherein the anode comprises a catalyst. ### Claim 14 (depends on 13) The method according to claim 13, wherein the catalyst comprises platinum. ### Claim 15 (depends on 13) The method according to claim 13, wherein the catalyst comprises gold. ### Claim 16 A method of performing an electrochemical reaction in an electrochemical cell comprising electrodes separated by an ion-exchange membrane, which comprises including a reactant that is capable of undergoing or imparting a change in visual appearance on oxidation or reduction; and monitoring any change in visual appearance. ### Claim 17 (depends on 16) The method according to claim 16, wherein the reactant is or is present in a fuel. ### Claim 18 (depends on 17) The method according to claim 17, wherein the fuel is an alcohol. ### Claim 19 (depends on 18) The method according to claim 18, wherein the alcohol is present in an aqueous solution comprising calcium hydroxide. ### Claim 20 (depends on 18) The method according to claim 18, wherein the alcohol is methanol or ethanol. ### Claim 21 (depends on 16) The method according to claim 16, wherein the reactant is an oxidant. ### Claim 22 (depends on 21) The method according to claim 21, wherein the oxidant is aqueous potassium permanganate. ### Claim 23 (depends on 16) The method according to claim 16, wherein the cell is in the form of a membrane-electrode assembly (MEA) or a stack of MEAs. ### Claim 24 An electrochemical cell comprising electrodes separated by an ion-exchange membrane, wherein the cell comprises a liquid including a reactant that is capable of undergoing or imparting a change in visual appearance upon oxidation or reduction, and wherein the cell comprises a window through which the visual appearance of the liquid can be observed. ### Claim 25 (depends on 24) The cell according to claim 24, wherein the reactant is or is present in a fuel. ### Claim 26 (depends on 25) The cell, according to claim 25, wherein the fuel is an alcohol. ### Claim 27 (depends on 26) The cell, according to claim 26, wherein the alcohol is present in an aqueous solution comprising calcium hydroxide. ### Claim 28 (depends on 26) The cell, according to claim 26, wherein the alcohol is methanol or ethanol. ### Claim 29 (depends on 24) The cell, according to claim 24, wherein the reactant is an oxidant. ### Claim 30 (depends on 29) The cell, according to claim 29, wherein the oxidant is aqueous potassium permanganate. ### Claim 31 (depends on 24) The cell, according to claim 24, wherein the cell is in the form of a membrane-electrode assembly (MEA) or a stack of MEAs.