- Fuel cell research and testing is important for advancing green energy technology to meet the increasing demand of sustainable, renewable energy
- Highly accurate, precise, and repeatable flow control and measurement is critical for the intricate research and testing process
- Bronkhorst flow meters and controllers can facilitate reliable testing processes that allow fuel cells to be designed for higher efficiency
How Flow Meters Support an Energetic Future
Fuel cell research plays an important role in our energy transition supporting an energetic future. Fuel cells make it possible to transform hydrogen from renewable energy sources back to electricity. Mass flow control is a key factor in fuel cell development and testing, as fuel cells highly depend on fluidic parameters during testing.
Fuel Cell Research, Development, and Manufacturing
A new fuel cell design depends on a lot of parameters. And to test it correctly, you need to know the properties and number of gaseous parameters, as accurately as possible. The final test result is never better than how precise your input is controlled.
Fuel cell test houses, universities, and fuel cell test equipment manufacturers benefit from this basic knowledge when they use our flow control and measurement technology.
Why Mass Flow control and Measurement is Important
For those who are not familiar with fuel cells, let’s start with some basics. For example, PEM-type fuel cells (Polymer Electrolyte Membrane), depend on executing an electrochemical process, amongst other types of fuel cells. Therefore, it can only supply electrical current when it receives the following fluids:
- The anode needs optimal feed of humidified hydrogen
- The cathode needs optimal feed of humidified oxygen or air
This is preferably executed with optimal ‘stoichiometry’, which is a key factor for fuel cell efficiency. Read here more about the role of flow control in producing hydrogen.
The efficiency of the fuel cells depends on the composition and amount of humidified hydrogen and air, their flow speed, pressure conditions, and the pressure difference across membranes. The sweet spot for optimal performance is also influenced by external factors, such as the required electrical load together with ambient and fluid temperatures.
Another factor in play is the fuel cell design itself and its attached parameters, such as membrane thickness, type of electrolyte, active electrode surface area, and the effectivity of gas diffusion layers.
Mass Flow Control in Fuel Cell Testing
The graph schematic below gives an indication of mass flow control instruments as seen in test-setups. It shows where you can apply our mass flow instruments. To keep it simple: The flow meters and pressure instruments take care of the main liquid, gas, and pressure measurement and control related tasks. It’s simple to see the fluidic dependencies and interactions.
The represented Controlled Evaporator Mixer is typically used for low flow and low humidification levels. For higher flows we often advise towards cascaded systems.
Reasons to Use Mass Flow Controllers
The result of any test, is as good as the sum of accuracies
Consider that all fluidic control and measured dependencies always interact simultaneously. Knowing this, you can understand that these have a major influence on functional tests and stress tests, for both single cells and fuel cell stacks. Many test goals for fuel cells or for fuel-treating systems are affected by this. For example, when determining performance indicators and characterizations (according to IEC 62882-series or other standards). The realized input feed control accuracy can have a huge impact on your systematic uncertainty.
Bronkhorst FLEXI-FLOW Instrument for Pressure and Flow Measurement and Control
The FLEXI-FLOW features a new concept of measuring mass flow and pressure is based on a technology called TCS, Through Chip Sensor. This new sensor exists of a capillary tube made with MEMS technology and combines the best of two worlds; a fast and stable flow sensor applied in our proven bypass construction for a reliable and highly accurate flow measurement.
The FLEXI-FLOW truly is flexible to use and can both measure and control mass flow and pressure in one instrument. This gas flow controller is one of the most compact ones in our product portfolio. It allows users to save space in their system and a reduction of weight and was designed specially with analytical and research labs in mind.
Bronkhorst EL-FLOW Base Series Gas Mass Flow Controller
The EL-FLOW Base Series is another one of Bronkhorst’s gas mass flow controllers that can provide the accuracy and repeatability required for users to mix their own calibration gas. Up to 12 gas cylinders are connected to an equal amount of mass flow controllers. The accurately controlled gas flows enter a mixing chamber, after which, the mixture is fed to a gas chromatograph for calibration purposes.
Bronkhorst IN-FLOW, High Flow Meter
Another good choice to control your fuel cell related- flow, pressure, and density conditions is the Bronkhorst IN-FLOW, High Flow Meter. This device is based on a thermal bypass mass flow measuring technology. A mass flow controller based on this principle can achieve the most flexible, accurate and repeatable fluidic control, including:
- Reliable control with fast on-board (direct valve) PID control
- Instant mass-based measurement (no volume and P+T based conversions to mass)
- Higher systematic accuracy for fluidic control & measurement
- More flexible mix & ratio feed control for H2/N2/H2O and O2/H2O and other gases
- Independent anode and cathode flow speed- and pressure control
- Better support for profile switching or characteristics change for load change, durability cycling, polarization, purging, etc.
Bronkhorst IQ+FLOW, Ultra Compact Pressure and Flow Meter and Controller
Bronkhorst has developed the IQ+FLOW mass flow sensor, which uses micro solid state technology (MEMS) that reduces the footprint dimension to 0.75″, or half of conventional mass flow meters. The IQ+FLOW offers ultra compact flow and pressure meters and controllers.
- Lowest range 0.2…10 mln/min
- Highest range 0.1…5 ln/min
From Single Cell to Large Set-ups (High Flow)
Our full line of flow meters and controllers surely offers a great solution to fit your exact requirements. From the ultra compact FLEXI-FLOW and IQ+FLOW to the industrial style EL-FLOW Base or high flow IN-FLOW, we can support your process from research and development to full scale operations.
We have mass flow control instruments available for OEM applications, laboratory applications as well as industrial versions. In case multiple gaseous fuels are used, products support on-board multi-fluid configuration.