FAQ
FAQ - Stacks
A fuel cell stack is a stack of many individual fuel cells connected in series to achieve a higher electrical voltage and power output. It forms the heart of a hydrogen-based propulsion or energy system.
A single cell consists of three main components:
- Anode (negative terminal): Hydrogen is fed into this.
- Cathode (positive terminal): Oxygen from the air flows into this.
- Electrolyte membrane: This separates the anode and cathode and allows only protons to pass through.
During the electrochemical reaction, hydrogen is split into protons and electrons at the anode. The protons migrate through the membrane to the cathode, whilst the electrons flow through an external circuit, thereby generating electricity. At the cathode, protons, electrons and oxygen combine to form water.
- Zero emissions: The only by-products are water vapour and heat.
- High efficiency: Chemical energy is converted directly into electricity.
- Scalability: Output can be adjusted by varying the number of cells in the stack – from small-scale applications to large vehicles or industrial plants.
A laboratory stack is a modular, demountable test setup comprising 5 to 20 cells, designed specifically for research and development. It is used to investigate electrochemical processes under realistic yet controlled conditions and to quickly replace individual components such as membranes or seals.
- Validation: Testing of materials from basic research in stack operation.
- Operational optimisation: Determination of optimal operating parameters such as humidity, pressure and temperature.
- Degradation studies: Investigation of ageing processes and service life.
Laboratory stacks with MEAs come with pre-installed membrane electrode assemblies, whereas laboratory stacks without MEAs are modular and allow these assemblies to be replaced for testing purposes. Both types are designed for the research and development of electrochemical processes.
QuinTech offers fuel cell stacks in various power ratings:
- Stacks up to 1 kW
- Stacks up to 5 kW
- Stacks up to 21 kW
Seals ensure:
- Sealing of the gas compartments to prevent hydrogen or oxygen leaks.
- Media separation, so that coolant does not enter the reaction zones.
- Mechanical compensation for manufacturing tolerances and even pressure distribution.
FAQ – Test cells
Test cells are specifically designed for the scientific investigation and industrial development of energy converters. In fuel cell research, they help to analyse and optimise the interaction between catalysts, membranes and gas diffusion layers. In electrolysis development, they are used to test new materials for water splitting and to improve the efficiency of green hydrogen production.
Electrolysis test cells are used to study water splitting in detail to produce green hydrogen. They enable the testing of new materials for durability and efficiency, with a view to developing cost-effective hydrogen production processes.
AEM (anion exchange membrane) cells represent a cutting-edge field of research in which concepts that do not use precious metals are being tested. Test cells for AEMs enable the precise analysis of anion conductivity and the chemical stability of new polymer membranes under real operating conditions.
- Fundamental characterisation: Determination of current-voltage curves, impedance spectra and degradation rates.
- Material screening: Rapid evaluation of new catalyst materials and membrane formulations.
- Standardisation: Establishment of reproducible test conditions for the transition from basic research to industrial application.
Key components include:
- Membranes: Ion separation and electrical insulation.
- Catalysts: Accelerate chemical reactions; typically precious metals such as platinum or iridium.
- Electrodes: electrochemically active layers on gas diffusion layers made of carbon or titanium.
- Seals: prevent leaks and ensure safe media separation and pressure distribution.
FAQ – Components for fuel cells and electrolysis
- A FM-FAA-3 membrane is best suited for a weak KOH solution up to a maximum of 1 mol
- FM-FAAM membranes are suitable for a strong KOH solution above 6 mol
- For concentrations in between, a thin FM-FAAM membrane should be selected
It is important to prevent the membrane from drying out. They should therefore remain in their original packaging until use and be stored in a cool, clean place. Please also refer to the information in the data sheet.
Catalyst inks (emulsions consisting of catalyst particles, ionomers and solvents) are applied by spraying, doctor blade coating or slot die coating. Once the solvent has evaporated, the porous, active catalyst layer remains.
The best way to check the viability of the membrane after storing for a long time is by comparing its mechanical properties to those reported on the CoA for each specific batch. If you have DMA, you can measure the membrane as it is on the roll, as well as after soaking in DI water and drying. The soak and dry test is more representative of how the membrane will be in an electrolyzer. If you don't have DMA, you can test if the membrane cracks or breaks when folding in both the dry state and after a soak and dry cycle. A fully degraded membrane will crumble and fall apart when folded.
A secondary way to confirm the chemical viability of the membrane would be to test the ion exchange capacity of the membrane after exchanging it to chloride form, as found in the typical values section of the CoA.
The colour of the membrane can vary for every production batch. That’s normal and no sign for a manufacturing defect.
A CCM is a catalyst-coated membrane comprising three layers: the central membrane and catalyst layers on the anode and cathode sides. It is the heart of the cell and is crucial to its efficiency, performance and service life.
A CCM should be stored in a suitable protective packaging and in a dry and cool place.
The coating is applied either directly using processes such as screen printing, slot die coating or inkjet printing, or indirectly via decal transfer printing, in which the electrode layers are transferred onto the membrane.
The “C” on the membrane refers to the cathode and the other side is the anode.
Electrodes are the electrochemically active layers within the cell. Each cell has two electrodes: the anode and the cathode. In gas diffusion electrodes (GDE), the active layer—comprising a catalyst and an ionomer—is deposited onto a gas diffusion layer made of carbon or titanium.
Gas diffusion layers are porous layers situated between the bipolar plate and the electrochemically active layer. They ensure an even distribution of the reaction gases, drain away the product water and maintain electrical conductivity between the catalyst and the bipolar plates.
No, the GDL can be used directly.
Bipolar plates electrically and mechanically separate the individual cells in the stack. They contain fine channels (flow fields) for the precise distribution of reaction gases and the removal of water and heat. Graphite plates are corrosion-resistant, lightweight and thermally conductive, and are increasingly being used as a cost-effective alternative to titanium plates.
The MEA consists of a catalyst-coated membrane and gas diffusion layers on both sides. It facilitates the electrochemical reaction, regulates mass transfer and electrically isolates the electrodes from one another. The MEA influences the power density, efficiency and service life of the fuel cell.
MEA’s should be stored in damp-proof or sealed, moisture-resistant packaging at room temperature. As they are thin and therefore susceptible to scratches or dents, they should be stored flat and without any dents.
- Heat the cell to 60 °C
- Anode and cathode fully humidified
- Set the voltage to 0.6 V
- The current starts too rise
- The MEA is conditioned, when the current is stable and not increasing anymore. This could take a couple of hours
We offer fuel cell systems with power outputs of up to 5 kW.
FAQ – Education and Demonstration
Teaching models are modular systems designed for schools, universities and training centres that facilitate hands-on experimentation. They consist of plug-in components such as solar cells, electrolysers and fuel cells, and feature interfaces for data logging.
Demonstration models provide a realistic visualisation of fuel cell technology, for example in miniature cars or power stations, often featuring transparent casings. They are ideal for trade fairs, showrooms and customer presentations to demonstrate the technology’s suitability for everyday use.
FAQ – Delivery times and shipping information at QuinTech
The delivery time will depend on the individual agreement we reach with you. Once the order has been placed, we will inform you of the estimated delivery time for your product or solutio
Should any unexpected delays occur, we will inform you immediately. We will do our utmost to deliver your order as quickly as possible.
We accept responsibility for delivery delays caused by us. However, delays may occur due to unforeseeable events or force majeure beyond our control, for which we cannot accept liability.
As our products and solutions vary from case to case, there is no standard delivery time. We will always inform you personally of the exact delivery time for your order.
Please contact us well in advance if you require an urgent delivery. We will work with you to find the best way to meet your requirements.
Yes, delivery charges are added to the product prices and are calculated separately. The exact delivery charges are listed for each product and will be displayed during the ordering process.
Once your order has been dispatched you will usually receive a dispatch confirmation so that you can track the status of your delivery.
The delivery deadline is deemed to have been met as soon as the goods have left the QuinTech location or notification has been given that they are ready for dispatch.
The products are dispatched to you once they are ready for dispatch. Delivery charges are added to the product price
Yes, the delivery charges are shown separately during the ordering process, so you can view them before completing your order.
FAQ – Payment terms at QuinTech
Prices are quoted ex works and do not include packaging or delivery costs, unless otherwise agreed.
Payment terms are set out individually in the contract or in the order confirmation. Unless otherwise agreed, the payment terms specified therein apply.
Standard payment methods such as bank transfer are accepted. Individual payment terms can be agreed upon by arrangement.
In the event of late payment, QuinTech reserves the right to charge interest on arrears and, if necessary, to take further legal action.
Yes, individual payment terms are possible and will be set out in the contract.