Cerium-Incorporated PEM for Fuel Cell Radical Resistance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Polymer electrolyte fuel cells face significant voltage degradation and membrane deterioration due to hydrogen peroxide or peroxide radicals, especially under low or no humidification conditions, which affects their stability and efficiency for long-term operation.

Innovation Solution

A polymer electrolyte membrane incorporating cerium ions and an organic compound, such as crown ethers, to form an inclusion compound that enhances the membrane's resistance to hydrogen peroxide or peroxide radicals, combined with a membrane-electrode assembly design featuring a catalyst layer and ion exchange resin for improved durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a perfluorocarbon polymer membrane is used to improve radical stability, then reliability is improved, but voltage degradation occurs under low humidification conditions

Engineering Contradiction:

Improveradical stabilityVSAvoidvoltage degradation

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

Cerium ions are introduced as an intermediary substance within the membrane structure. These cerium ions act as mediators that scavenge peroxide radicals, preventing them from attacking and degrading the polymer backbone. The cerium ions are incorporated into the membrane through ion exchange with the sulfonic acid groups, creating a protective mechanism that maintains voltage stability even under low humidification conditions where radical formation is most problematic.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If operation under low humidification is implemented to improve system efficiency, then productivity is improved, but membrane deterioration accelerates

Engineering Contradiction:

Improvesystem efficiencyVSAvoidmembrane stability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The invention converts the harmful effect of low humidification operation into a benefit. By introducing cerium ions that specifically target and neutralize peroxide radicals, the system can operate under low humidification conditions (which normally accelerate degradation) while actually improving overall efficiency. The cerium ions transform the potentially damaging radical species into harmless products, allowing the system to exploit the efficiency benefits of low humidification operation without suffering the usual membrane deterioration penalties.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Duration of action of moving object

If long-term operation is pursued to achieve stable power generation, then duration of action is improved, but voltage stability deteriorates due to radical attack

Engineering Contradiction:

Improveoperation durationVSAvoidvoltage stability

Core Design Contradiction:

Duration of action of moving objectVSStability of the object's composition

Solution Approach 1:

The cerium ions are pre-incorporated into the membrane structure before operation begins. This preliminary action ensures that the radical scavenging capability is already in place and active from the start of operation. The cerium ions are distributed throughout the membrane matrix through ion exchange, creating a built-in protection system that is ready to neutralize peroxide radicals as soon as they form, thereby maintaining voltage stability throughout long-term operation.

Inventive Principle:

Principle #10Preliminary action

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

The membrane-electrode assembly with cerium-based inclusion compounds demonstrates enhanced durability and stable power generation over a long period, regardless of humidification conditions, maintaining high energy efficiency and voltage stability.

Implementation Method 1

contains any one of the following (a) to (c): (a) cerium ions and an organic compound (X) capable of forming an inclusion compound with cerium ions; (b) an inclusion compound (Y) comprising the organic compound (X) including cerium ions

Methodology Applied

Scientific EffectInclusion compound formation:

Implementation Method 2

a polymer electrolyte membrane which comprises a polymer electrolyte having sulfonic acid groups, and contains any one of the following (a) to (c): (a) cerium ions and an organic compound (X) capable of forming an inclusion compound with cerium ions... has excellent resistance to hydrogen peroxide or peroxide radicals

Methodology Applied

Scientific EffectRadical resistance:

Implementation Method 3

a proton conductive ion exchange membrane is commonly employed as a polymer electrolyte membrane

Methodology Applied

Scientific EffectIon exchange: Ion Exchange

Data Source

PatentUS9711817B2Polymer electrolyte membrane and membrane-electrode assembly for polymer electrolyte fuel cell

Publication Date: 2017.07.18 AGC INC

AI summary

A polymer electrolyte membrane which comprises a polymer electrolyte having sulfonic acid groups, and contains any one of the following (a) to (c):(a) cerium ions and an organic compound (X) capable of forming an inclusion compound with cerium ions;(b) an inclusion compound (Y) comprising the organic compound (X) including cerium ions; and(c) at least one of cerium ions and the organic compound (X), and the inclusion compound (Y).