What are the different types of fuel cells?
A range of fuel cells are available for different applications, distinguished by characteristics such as the catalysts they use and their operating temperatures. We explain the main differences between proton exchange membrane, solid oxide, alkaline, phosphoric acid and molten carbonate fuel cells, and look at their top applications below.
Proton Exchange Membrane Fuel Cells (PEMFC)
Proton Exchange Membrane fuel cells convert chemical energy from hydrogen into electricity through an electrochemical reaction. The electrolyte is a solid polymer membrane and hydrogen is used as the fuel.
PEM fuel cells have a number of advantages over other fuel cell types, some of which include high power densities and fast start-up times due to relatively low operating temperatures. They are easy to integrate into a wide range of applications and produce clean energy, with the primary by-product being water.
You can learn more about the proton exchange membrane fuel cells we manufacture in our FAQs section here.
Operating temperature: 60-100°C.
Applications
Applications include unmanned aerial vehicles (UAVs), material handling equipment, portable power systems, backup power and automotive industries.
Solid Oxide Fuel Cells (SOFC)
Solid Oxide fuel cells operate at very high temperatures and use a solid ceramic electrolyte. They use hydrogen, natural gas, biogas and other hydrocarbons as fuel.
The benefits of a SOFCs include high combined heat and power efficiency, long-term stability and low emissions. The main disadvantage is the very high operating temperature, leading to longer start-up times.
Operating temperature: 500-1,000°C.
Applications
Applications include large-scale stationary power generation and auxiliary power units for vehicles.
Alkaline Fuel Cells (AFC)
Alkaline fuel cells use an alkaline electrolyte, usually potassium hydroxide.
This fuel cell type can use hydrogen as fuel and provides sustainable energy at a lower cost and higher power density compared to most other fuel cells. A disadvantage for AFCs is the intolerance of the electrolyte towards CO2 which can result in a decrease in performance. Avoiding this issue requires purification of the air feed which adds complexity to the AFC system.
Operating temperature: 60-90°C.
Applications
Applications include space applications and military uses.
Phosphoric Acid Fuel Cells (PAFC)
Phosphoric Acid fuel cells use liquid phosphoric acid as their catalyst to produce electricity through an electrochemical reaction between hydrogen and oxygen.
The main benefit of PAFCs is that they are highly energy efficient and reduce energy waste. They also have low electrolyte volatility and offer long-term stability.
Operating temperature: 150-200°C.
Applications
Applications include commercial and industrial stationary power generation.
Molten Carbonate Fuel Cells (MCFC)
Molten Carbonate fuel cells use an electrolyte composed of a molten carbonate salt mixture, usually a combination of lithium carbonate and potassium carbonate.
MCFCs can achieve efficiencies of 45-50% and when used in combined heat and power systems, the efficiency can reach 85%. Another benefit is that they can operate on a variety of fuels, including natural gas, biogas, hydrogen and other hydrocarbons. These fuel cells are also durable at high temperatures and allow the use of non-precious metal catalysts, reducing operating costs.
Operating temperature: 600-700°C.
Applications
Applications include large-scale stationary power generation.
Our PEM fuel cells
At Intelligent Energy, we manufacture PEM fuel cells and have 30 years of experience in the development and manufacture of zero-emission hydrogen fuel cell power systems. We manufacture PEM fuel cells for applications including automotive, aerospace, power generation, telecoms, marine, rail and materials handling.
If you’d like to find out more about our capabilities and how we can help your business with its PEM fuel cell requirements, please get in touch with us today. Complete our contact form or send us an email at sales@intelligent-energy.com.