Electrochemical Innovation Starts with Better Materials
Electrochemical technologies, such as fuel cells and redox flow batteries, are reshaping how we produce, store, and utilize energy. At the core of these systems is a critical component: the ion exchange membrane. This thin layer doesn’t separate reactants; it governs the system’s efficiency, durability, and overall performance.
PFSA membranes like Nafion® have led the market for years, especially in low-temperature PEM fuel cells operating around 60–80 °C with full humidification. But today’s systems demand more. Higher temperatures, harsh chemical conditions, and cost pressures are pushing the limits of traditional materials.
Celazole® PBI offers a proven alternative. PBI membranes doped with phosphoric acid operate reliably in high-temperature PEMFCs (150–200 °C) without needing external humidification. The acid guarantees proton conductivity, while the PBI backbone provides outstanding thermal and chemical stability.
These features simplify system design and improve tolerance to contaminants like carbon monoxide. Higher temperatures also enhance reaction kinetics and reduce catalyst poisoning, making Celazole PBI an ideal membrane solution for reformed fuel and industrial hydrogen systems.
Electrolyzers Pushing New Limits
As demand for green hydrogen rises, electrolyzer systems are being pushed to operate at higher temperatures and current densities. Traditional PEM electrolyzers using PFSA membranes face limitations under these conditions, including oxidative degradation, hydration sensitivity, and high material costs.
Celazole® PBI membranes provide a high-temperature alternative and offer strong performance in demanding electrochemical environments. Acid-doped PBI has shown excellent durability, conductivity, and compatibility with lower-cost catalysts.
Key benefits demonstrated in electrolyzer systems include:
- Stable operation at elevated temperatures without the need for external humidification
- Improved oxidative stability compared to many hydrocarbon and PFSA-based membranes
- Resistance to mechanical creep and chemical degradation over thousands of hours of continuous use
- Support for non-precious metal catalyst systems, allowing potential reductions in overall system cost
Flow Batteries and Crossover Control
Redox flow batteries present a different membrane challenge. Here, the membrane’s role is less about conductivity and more about selectivity. It must allow ionic charge carriers, often protons or sulfate ions, to pass while preventing the crossover of redox-active species, such as vanadium.
In this application, membrane permeability directly affects efficiency and lifetime. PBI membranes, particularly when reinforced or blended with barrier layers, offer low crossover rates and excellent chemical stability in acidic electrolytes. Their thermal tolerance also helps mitigate degradation during prolonged cycling.
While PFSA membranes, such as Nafion, have been widely used in commercial systems, they suffer from excessive vanadium crossover and carry a high price tag.
Alternatives based on Celazole PBI and other aromatic polymers are gaining traction for their balance of cost, performance, and durability.
Anion Exchange Systems on the Rise
While many electrochemical systems rely on proton exchange, anion exchange membrane (AEM) fuel cells and electrolyzers are gaining traction, especially in alkaline environments, where they enable more affordable, non-precious metal catalysts.
Although Celazole® PBI is not inherently an anion conductor, it plays a valuable role in next-generation AEM designs. As a mechanically robust support layer, PBI enhances membrane stability when integrated with functionalized polymers made for hydroxide transport.
In AEM and hybrid systems, PBI contributes to:
- Mechanical reinforcement of thinner, chemically sensitive AEM layers
- Improved thermal and chemical stability, supporting longer membrane lifetimes
- Composite architectures where PBI enables scalable fabrication of high-performance, alkaline-compatible membranes
From Bench to Industry
Perhaps most compelling is the track record PBI has built outside the lab. Acid-doped PBI membranes have powered commercial-scale HT-PEM fuel cells, demonstrated long-term durability in electrolyzers, and supported pilot flow battery deployments.
These membranes can be fabricated into thin films, reinforced composites, or even multi-layer assemblies tailored to system needs. They are compatible with common fabrication methods, such as casting and lamination, and integrate readily with electrode substrates and sealing materials.
With global pressure mounting to decarbonize transportation, industrial heating, and energy storage, electrochemical systems are scaling quickly.
The Material to Build On
Most polymers fail under extreme heat, harsh acids, and high current density; however, Celazolele® PBI thrives under these conditions. Engineered for stability under pressure, this membrane material provides system designers and engineers with a reliable option when performance and reliability are non-negotiable.
Celazole PBI is becoming the go-to solution for electrochemical systems operating at the edge of conventional material limits, from high-temperature water electrolyzers to humidifier-free PEM fuel cells and low-crossover redox flow batteries. It’s not designed for every application, but it consistently delivers for the ones that matter most.
Connect with PBI Performance Products to request a sample, speak with our technical team, or learn how we can be integrated into your next-generation electrochemical platform.