Fuel Cell Separator Position Control for Pressure Drop

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Fuel cell stacks face suboptimal pressure drop conditions due to the need for a compromise design that doesn't adequately address varying operational requirements, leading to inefficiencies in reactant gas flow and water removal across the cathode and anode sides.

Innovation Solution

Controlling the position of a cell separator, such as a sub-gasket, within the feeder region of the fuel cell stack to alter flow resistance by managing the fluid state of reactant gases, thereby adjusting pressure drops across the cathode and anode sides to optimize flow rates and channel volumes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a compromise pressure drop design is used to satisfy all stack operating conditions, then the design can operate under various conditions, but the pressure drop is not optimal for any specific condition

Engineering Contradiction:

Improveadaptability to various operating conditionsVSAvoidperformance efficiency

Core Design Contradiction:

Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent applies the dynamics principle by making the cell separator position adjustable rather than fixed. The cell separator can dynamically move between intruding into the flow channel and being retracted from it, allowing the system to adapt its pressure drop characteristics in real-time based on operating conditions. This dynamic adjustment capability resolves the contradiction by enabling both versatility across conditions and optimal performance for specific conditions through active control.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the pressure drop parameter by controlling the cell separator position. By adjusting the degree of intrusion of the cell separator into the flow channel, the system can modify the flow resistance and thus the pressure drop across the membrane electrode assembly. This parameter change enables the system to achieve optimal performance for different operating conditions while maintaining adaptability.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If the cell separator is positioned to optimize one side's pressure drop, then that side's performance improves, but the other side's performance may deteriorate

Engineering Contradiction:

Improveperformance of one sideVSAvoidperformance of other side

Core Design Contradiction:

ProductivityVSAdaptability or versatility

Solution Approach 1:

The dynamic positioning of the cell separator allows the system to adjust its configuration based on which side requires optimization. The controller can command the cell separator to specific positions to prioritize either the anode side or cathode side performance as needed, while still maintaining the ability to serve both sides adequately through intermediate positions.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

By changing the cell separator position parameter, the system can shift the pressure drop distribution between the anode and cathode sides. This parameter adjustment enables selective optimization of one side while maintaining acceptable performance on the other side, resolving the contradiction between specialized performance and overall adaptability.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If a fixed channel configuration is used in the feeder region, then the design is simple, but it cannot dynamically adjust pressure drop for different operating conditions

Engineering Contradiction:

Improvechannel design complexityVSAvoidpressure drop adjustment capability

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The cell separator serves a dual function: it acts as a structural separator between anode and cathode channels while also functioning as a dynamic flow resistance controller. By utilizing the cell separator's position to control pressure drop, the system achieves adaptability without adding separate complex control mechanisms, thus maintaining relative design simplicity while gaining dynamic adjustment capability.

Inventive Principle:

Principle #25Self-service

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 allows for dynamic pressure drop manipulation, reducing channel design complexity and enhancing water removal capabilities while accommodating different system operating conditions, thereby improving fuel cell stack performance.

Implementation Method 1

controlling a reactant gas state in the cathode or the anode flow channels for one of the cathode side or the anode side to move a cell separator in a feeder region into or out of the cathode or the anode flow channels in the opposing cathode side or anode side

Methodology Applied

Scientific EffectPressure gradient: Pressure Gradient

Data Source

PatentUS10186723B2Method to actively control cell pressure drop during operation

Publication Date: 2019.01.22 GM GLOBAL TECHNOLOGY OPERATIONS LLC

AI summary

A method for controlling a pressure drop across the anode side or the cathode side of a fuel cell stack by controlling the intrusion of a cell separator into the flow channels in a feeder region of the stack so as to create a larger pressure volume on a pressure bias side of the stack. The method controls the flow rates of one or both of the cathode and anode reactant gases so as to cause the cell separators in an inlet feeder region and/or an outlet feeder region to move relative to the anode side and the cathode side so as to change a flow volume in the inlet feeder region and/or the outlet feeder region to control the pressure drop.