Fuel Cell Anode Catalyst Recovery Through CO Oxidation Pulsing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The anode catalyst in fuel cell stacks used in vehicles undergoes degradation due to carbon monoxide adsorption, leading to reduced catalytic activity and fuel cell durability.
Innovation Solution
An apparatus and method that increase the hydrogen flow rate above a reference value, estimate nitrogen concentration based on hydrogen concentration, and either pulse-control the output voltage or induce a reverse voltage of the fuel cell stack to electrochemically oxidize carbon monoxide adsorbed on the anode catalyst.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the fuel cell stack operates continuously under normal conditions, then productivity is maintained, but carbon monoxide accumulates on the anode catalyst surface causing degradation
Solution Approach 1:
The patent implements periodic reverse voltage application to the fuel cell stack. The controller periodically applies a reverse voltage (opposite polarity to normal operation) for a predetermined time interval, which causes carbon monoxide adsorbed on the anode catalyst surface to be desorbed and removed, thereby restoring catalytic activity without requiring system shutdown
Solution Approach 2:
The patent recovers the catalytic activity of the anode catalyst by removing (discarding) the carbon monoxide that has accumulated on its surface. Through reverse voltage application, the harmful carbon monoxide is electrochemically removed from the catalyst surface, allowing the catalyst to be recovered and continue functioning effectively
2Reliability
If carbon monoxide is removed from the anode catalyst surface, then catalytic activity is recovered, but additional control operations are required
Solution Approach 1:
The patent incorporates a feedback mechanism where the controller monitors the operational state of the fuel cell stack and automatically determines when reverse voltage application is needed. The controller counts the number of times reverse voltage has been applied and compares it against a predetermined threshold, automatically initiating reverse voltage operation when the threshold is reached, thereby reducing the need for complex manual control while maintaining effective catalyst recovery
Solution Approach 2:
The fuel cell stack performs its own catalyst maintenance through the reverse voltage mechanism. The system uses its own electrical infrastructure to periodically clean the anode catalyst surface of carbon monoxide deposits, eliminating the need for external cleaning systems or manual intervention, thus maintaining catalytic activity with minimal additional complexity
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 effectively recovers the degradation of the anode catalyst by oxidizing carbon monoxide, thereby maintaining the catalytic activity and enhancing the durability of the fuel cell stack.
Implementation Method 1
electrochemically oxidizing carbon monoxide adsorbed on the surface of the anode catalyst
Implementation Method 2
carbon monoxide (CO) generated by carbon corrosion is adsorbed on the surface of the anode catalyst
Data Source
AI summary
In an apparatus and method for recovering degradation of an anode catalyst, the apparatus increases a hydrogen flow rate supplied to the anode of the operating fuel cell stack above a normal value, estimates a nitrogen concentration of the anode based on the hydrogen concentration of the anode, and pulse-controls an output voltage of the fuel cell stack in response that the nitrogen concentration of the anode reaches a preset value, electrochemically oxidizing carbon monoxide adsorbed on the surface of the anode catalyst.