Heat and water management in fuel cells explained
Effective heat and water management is essential to the performance, reliability, and longevity of hydrogen fuel cells, especially proton exchange membrane fuel cells (PEMFCs).
At Intelligent Energy, our PEM fuel cells are engineered to maintain precise thermal and hydration balance for optimal performance and durability. This article explores how our fuel cells are engineered for optimal temperature and water control, leading to reliable performance across demanding environments.
Why heat and water management matters
All hydrogen fuel cells produce heat and water as natural by-products of the electrochemical process that generates electricity. For PEMFCs to operate at their best, both must be carefully regulated.
While some thermal and water management challenges are common across fuel cell types, PEMFCs have unique requirements. Intelligent Energy addresses these through tailored stack design, smart airflow, and material innovation.
- Heat: Efficient dissipation is key to protecting cell membranes and maximising power output.
- Water: The membrane must remain humidified to conduct protons, but without flooding the gas pathways.
Our systems are designed to maintain this delicate balance, even in tough conditions.
Air-cooled, open-cathode efficiency
Air-cooled, or open-cathode PEM fuel cells are especially common in lightweight systems like drones, small vehicles, or portable generators. These designs eliminate the need for a separate cooling circuit and the associated mass, instead using ambient air for both oxygen supply and heat removal.
Our approach brings key advantages:
- No liquid coolant = fewer components and lower system weight
- Integrated cooling and airflow = compact and efficient stack architecture
- Optimised airflow paths = even thermal distribution and hydration control
- Minimal maintenance = ideal for remote or high-duty applications
Our IE-POWER fuel cell modules are a great example, delivering robust performance with simplicity built in.
Managing heat and water in PEMFCs
Advances in fuel cell engineering have introduced several methods to address these challenges across different system sizes:
- Flow channel design: Structuring the bipolar plates and gas diffusion layers to optimise both airflow and thermal distribution. Serpentine or tapered channels can help minimise hotspots and direct water away from active surfaces.
- Material improvements: Using hydrophobic and hydrophilic coatings to aid in passive water movement. Advanced membranes retain water better under low humidity conditions, reducing the risk of dry-out.
- Active control systems: In higher-power or more demanding applications, variable-speed fans, embedded sensors, and dynamic control logic can respond to changing load conditions, adjusting cooling and airflow in real-time.
- Hybrid approaches: Some next-generation systems combine passive and active cooling and incorporate real-time diagnostics to prevent failure due to thermal runaway or flooding.
To learn more about how a hydrogen fuel cell stack operates, including its structure and real-world applications, read our insight on fuel cell stacks and their role in clean transport.
Efficiency and performance impacts
When thermal and water management systems work effectively, the benefits are clear:
- Higher power output with fewer performance losses at peak load
- Longer system life due to reduced mechanical and chemical stress
- Greater energy efficiency, which lowers hydrogen consumption and operating cost
Of course, overall efficiency also depends on how the hydrogen is produced. For an overview of green, blue, and grey hydrogen, visit our article on hydrogen production methods.
Solutions
Heat and water management in PEM fuel cells isn’t just a maintenance issue – it’s also a core part of system design. From the single-cell level to the full stack and cooling architecture, how effectively a fuel cell handles thermal and water loads determines how far, fast, and cleanly it can operate.
As fuel cells scale from portable to automotive and aerospace uses, these challenges become even more important. Solutions are emerging, but the balancing act between hydration and heat removal remains central to unlocking the full potential of hydrogen-powered systems.
If you’re exploring hydrogen fuel cell integration for your application and need expert insight on stack design or system cooling, get in touch with our team today.
FAQs
What happens if a PEM fuel cell gets too hot?
Excessive heat can damage the polymer electrolyte membrane, reduce catalyst efficiency, and cause uneven performance across the stack. Over time, this leads to permanent degradation. This is the case for all types of fuel cell.
Why does water management matter so much in PEMFCs?
Water must be present to keep the membrane conductive, but too much causes flooding, and too little dries the membrane out. Both conditions severely impact output and system life.
How is heat removed in air-cooled fuel cells?
In open-cathode designs, fans force ambient air through the system. This air carries away heat and also provides oxygen for the reaction. System design must ensure even airflow to avoid localised heating.
What role does hydrogen production play in overall efficiency?
Even the most efficient fuel cell can’t offset emissions if the hydrogen it uses is produced from fossil fuels. Green hydrogen offers the cleanest overall lifecycle.