Anion Exchange Ionomer Binders for Alkaline Fuel Cells.

Area of Science:

• Electrochemistry
• Materials Science
• Polymer Chemistry

Background:

• Anion exchange ionomer (AEI) binders are crucial for alkaline electrochemical devices, enabling ion transport and structural integrity.
• AEIs enhance performance and lifespan in fuel cells, electrolyzers, and batteries.
• Recent advancements focus on AEI compatibility with existing electrode materials and electrolytes.

Purpose of the Study:

• To review different types of AEI binders for alkaline fuel cells, particularly anion exchange membrane fuel cells (AEMFCs).
• To analyze the impact of chemical structure, functionalization, and conductivity on AEMFC performance.
• To discuss strategies for improving AEI stability and ion transport.

Main Methods:

• Summarizing AEI types based on chemical structure, functionalization, and conductivity.
• Analyzing factors influencing the balance between conductivity, mechanical strength, and water uptake (WU).
• Exploring recent material design advances (blends, composites, crosslinked ionomers) and electrode setups (asymmetric ionomer electrodes).

Main Results:

• AEI binder properties like functional groups, backbone flexibility, and ion exchange capacity are key performance determinants.
• Material innovations such as polymer blends, composites, and crosslinked ionomers enhance stability and ion transport.
• Asymmetric ionomer electrodes offer improved stability and ion transport.

Conclusions:

• Key challenges for AEIs include water management, alkaline degradation, phase separation, mechanical robustness, and long-term durability.
• Strategies to overcome these challenges are discussed, paving the way for improved AEMFCs.
• Future research should focus on scalable, economical AEI solutions and integration with new electrode materials for next-generation AEMFCs.