Fuel Cell Humidifier Using Rotating Shell for Exhaust Water Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for humidifying proton exchange membranes in fuel cells are inefficient, costly, and unable to adapt to varying power outputs or low temperature startups, often requiring large equipment and separate water replenishment, which increases costs and gas resistance.
Innovation Solution
A method and device that utilize the exhaust gas from fuel cells to condense and separate water, which is then delivered back to the intake gas to humidify the proton exchange membrane, using a rotating inner shell within an outer shell to facilitate heat exchange and centrifugal separation, reducing the need for additional de-ionized water and allowing for adaptive humidification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If water is directly added to the fuel cell to humidify the membrane, then the membrane hydration is improved, but the device complexity and operational cost increase due to separate water replenishment systems
Solution Approach 1:
The fuel cell system recycles its own exhaust gas to provide humidification, making the system self-sufficient. The exhaust gas, which contains water vapor from the electrochemical reactions, is redirected back to the anode side to humidify the incoming hydrogen and maintain membrane hydration without requiring external water addition systems
Solution Approach 2:
Instead of discarding the exhaust gas from the cathode side, the system recovers the water vapor contained within it. The exhaust gas is routed back to the anode inlet, where it serves as a humidification source, thereby recovering valuable water that would otherwise be wasted and eliminating the need for separate water replenishment
2Quantity of substance
If large equipment is used to humidify the gas by direct contact with water, then the humidification capacity is improved, but the device size and flexibility deteriorate
Solution Approach 1:
The exhaust gas serves multiple functions within the system: it acts as a humidification source for the anode inlet, serves as a heat transfer medium, and maintains system pressure balance. This multi-functional use of exhaust gas eliminates the need for dedicated humidification equipment, achieving high humidification capacity with minimal additional device size
Solution Approach 2:
The humidification function is merged with the exhaust gas recirculation system. Instead of using separate humidification equipment, the system combines the exhaust routing and humidification processes into a single integrated flow path, where the exhaust gas naturally humidifies the incoming hydrogen through direct contact in the manifold or inlet region
3Reliability
If de-ionized water is externally added to meet water requirements, then the membrane hydration is improved, but the operational cost increases
Solution Approach 1:
The system recovers water from the exhaust gas that would otherwise be discarded. By routing the exhaust back to the anode side, the water vapor contained in the exhaust serves to humidify the incoming hydrogen and maintain membrane hydration, eliminating the need to purchase and add de-ionized water externally
Solution Approach 2:
The fuel cell system produces its own humidification requirement through the water vapor generated during electrochemical reactions. The exhaust gas, rich in water vapor, is recycled back to the anode inlet, making the system self-sufficient for humidification needs and eliminating operational costs associated with external water addition
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces operational costs, enhances humidification efficiency, and enables dynamic response to varying power outputs while effectively humidifying at low temperatures, ensuring the proton exchange membrane remains hydrated without additional de-ionized water, thus improving fuel cell performance.
Implementation Method 1
cooling the hot and humid exhaust of the fuel cell to condense the water in the exhaust
Implementation Method 2
separating the water from the rest of the exhaust, and delivering the water to the intake gas of the fuel cell
Implementation Method 3
cooling the hot and humid exhaust of the fuel cell to condense the water in the exhaust with the intake gas for the fuel cell
Data Source
AI summary
The present invention discloses methods and devices for humidifying the proton exchange membranes of fuel cells with water obtained from the exhaust of the fuel cells. Humidifying methods include the following steps: cooling the hot and humid exhaust of the fuel cell to condense the water in the exhaust with the intake gas for the fuel cell; separating the water from the rest of the exhaust, and, delivering the water to the intake gas of the fuel cell. Humidifying devices include an outer shell containing a rotating inner shell. The inside of the inner shell forms a chamber where the exhaust is collected and cooled, and water is condensed and separated by the rotation of the inner shell. Openings on the inner shell allow the condensed water to pass through to one or more chambers containing the intake gas. The chambers are formed by the inside of the outer shell and the outside of the inner shell. Humidifying devices methods and devices of this invention can respond to the varying power output of the fuel cell. They also have high humidifying efficiency, low energy consumption, are cheap to operate, and work well during startup at low temperatures.