# US 10,312,536 B2 · On-board aircraft electrochemical system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,312,536 B2 - Document ID: US10312536B2 - Status: Granted - Kind: B2 - Application number: 15/151,132 - Filed: 2016-05-10 - Published: 2017-11-16 - Granted: 2019-06-04 - Earliest claimed: 2016-05-10 - Assignees: Hamilton Sundstrand Corporation - Applicants: Hamilton Sundstrand Corporation - Inventors: Jonathan Rheaume - Web page: https://patentgrep.com/patent/US10312536B2 ## CPC - H01M 8/04753: {of fuel cell reactants} - A62C 3/08: in aircraft {(A62C3/0207 takes precedence)} - A62C 99/0018: {using gases or vapours that do not support combustion, e.g. steam, carbon dioxide} - B64D 37/32: Safety measures not otherwise provided for, e.g. preventing explosive conditions - H01M 8/04201: {Reactant storage and supply, e.g. means for feeding, pipes} - H01M 8/04761: {of fuel cell exhausts} - H01M 8/04865: {Voltage} - H01M 8/1231: with both reactants being gaseous or vaporised - B64D 2041/005: {Fuel cells} - B64D 2045/009: {Fire detection or protection; Erosion protection, e.g. from airborne particles} - C25B 1/04: by electrolysis of water - H01M 2250/20: Fuel cells in motive systems, e.g. vehicle, ship, plane - Y02E 60/36: Hydrogen production from non-carbon containing sources, e.g. by water electrolysis - Y02E 60/50: Fuel cells - Y02T 50/40: Weight reduction - Y02T 90/40: Application of hydrogen technology to transportation, e.g. using fuel cells - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - A62C: FIRE-FIGHTING (fire-extinguishing compositions, use of chemical substances in extinguishing fires A62D1/00; spraying, applying liquids or other fluent materials to surfaces in general B05; alarm arrangements G08B, e.g. fire alarms actuated by smoke or gases G08B17/10) - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - C25B: ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR (anodic or cathodic protection C23F13/00; single-crystal growth C30B) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An onboard electrochemical system of an electrochemical cell including a cathode and an anode separated by an electrolyte separator is selectively operated in either of two modes. In a first mode of operation, water or air is directed to the anode, electric power is provided to the anode and cathode to provide a voltage difference between the anode and the cathode, and nitrogen-enriched air is directed from the cathode to an aircraft fuel tank or aircraft fire suppression system. In a second mode of operation, fuel is directed to the anode, electric power is directed from the anode and cathode to one or more aircraft electric power-consuming systems or components, and nitrogen-enriched air is directed from the cathode to a fuel tank or fire suppression system. ## Claims ### Claim 1 An on-board aircraft electrochemical system, comprising: an electrochemical cell comprising a cathode and an anode separated by an electrolyte separator; a cathode fluid flow path in fluid communication with the cathode that discharges nitrogen-enriched air; a nitrogen-enriched air flow path that receives nitrogen-enriched air from the cathode fluid flow path and delivers it to a fuel tank, a fire suppression system, or both a fuel tank and a fire suppression system; a first anode fluid flow path that directs water or air to the anode; a second anode fluid flow path that directs fuel to the anode; an electrical connection between an electric power source and the cathode and anode; an electrical connection between an electric power sink and the cathode and anode; and a controller programmed to alternatively operate the electrochemical cell in either: a first mode in which water or air is directed to the anode from the first anode fluid flow path, electric power is directed from the power source to the anode and cathode to provide a voltage difference between the anode and the cathode, and nitrogen-enriched air is directed from the cathode to the fuel tank, the fire suppression system, or both the fuel tank and the fire suppression system, or a second mode in which fuel is directed to the anode from the second anode fluid flow path, electric power is directed from the anode and cathode to the power sink, and nitrogen-enriched air is directed from the cathode to the fuel tank, the fire suppression system, or both the fuel tank and the fire suppression system. ### Claim 2 (depends on 1) The system of claim 1, wherein the controller is programmed to operate the electrochemical cell continuously in either the first mode or the second mode during aircraft operation. ### Claim 3 (depends on 1) The system of claim 1, wherein the nitrogen-enriched air flow path delivers nitrogen-enriched air to the fuel tank. ### Claim 4 (depends on 1) The system of claim 1, wherein the nitrogen-enriched air flow path delivers nitrogen-enriched air to either or both of the fuel tank and the fire suppression system. ### Claim 5 (depends on 1) The system of claim 1, wherein the controller is programmed to operate the electrochemical cell in the second mode during an emergency power system or fire suppression low rate of discharge, and in the first mode under normal conditions. ### Claim 6 (depends on 1) The system of claim 1, comprising a plurality of said electrochemical cells in electrical series in a stack. ### Claim 7 (depends on 1) The system of claim 1, wherein the electrolyte comprises a polymer electrolyte proton-transfer medium or phosphoric acid, and the first anode fluid flow path directs water to the anode for electrolysis during the first mode of operation. ### Claim 8 (depends on 7) The system of claim 7, further comprising a gas dryer disposed along the nitrogen-enriched air flow path to dry the nitrogen-enriched air. ### Claim 9 (depends on 7) The system of claim 7, wherein the electrolyte comprises a polymer electrolyte proton-transfer medium.