How is hydrogen stored in a hydrogen fuel cell?
Hydrogen fuel cells are a promising clean energy technology that use hydrogen gas to generate electricity. The hydrogen is stored in the fuel cell in a compressed or liquefied form, allowing it to be readily accessed and converted into electrical power. This article provides a detailed overview of how hydrogen is stored in hydrogen fuel cells.
Compressed Hydrogen Storage
One of the most common methods of storing hydrogen in fuel cells is through compressed hydrogen storage. In this approach, hydrogen gas is compressed and stored at high pressures, typically between 350 to 700 bar (5,000 to 10,000 psi). The compressed hydrogen is stored in specialized high-pressure tanks or cylinders made of materials like carbon fiber-reinforced polymer composites. This allows a significant amount of hydrogen to be stored in a relatively small volume, making it suitable for use in vehicles and other applications where space is limited.
Liquefied Hydrogen Storage
Another method of storing hydrogen in fuel cells is through liquefaction. Hydrogen gas is cooled to extremely low temperatures, around -253°C (-423°F), causing it to liquefy. Liquefied hydrogen has a much higher energy density than compressed hydrogen, allowing more hydrogen to be stored in the same volume. However, the liquefaction process is energy-intensive and requires specialized cryogenic storage tanks to maintain the low temperatures.
Solid-State Hydrogen Storage
In addition to compressed and liquefied storage, hydrogen can also be stored in solid-state materials, such as metal hydrides or complex hydrides. These materials can reversibly absorb and release hydrogen, providing a safe and compact way to store the gas. The hydrogen is stored by forming chemical bonds with the solid-state material, and it can be released when needed by applying heat or reducing the pressure. Solid-state hydrogen storage is still an emerging technology, but it has the potential to provide a safer and more efficient alternative to compressed or liquefied hydrogen storage.
Fuel Cell Operation and Hydrogen Storage
In a hydrogen fuel cell, the stored hydrogen is combined with oxygen from the air to generate electricity through an electrochemical reaction. The hydrogen is fed into the fuel cell, where it reacts with oxygen to produce water, heat, and electricity. The electricity can then be used to power various devices or be stored in batteries for later use. The choice of hydrogen storage method depends on factors such as the specific application, the required energy density, and the safety and cost considerations.
Overall, the storage of hydrogen is a critical aspect of hydrogen fuel cell technology, and the various storage methods offer different advantages and challenges. As the use of hydrogen fuel cells continues to grow, the development of efficient and safe hydrogen storage solutions will be crucial for the widespread adoption of this clean energy technology.
How is hydrogen stored in a Toyota Mirai?
The hydrogen that powers the Mirai is stored at a high pressure of 700 bar in two compact, lightweight tanks. We have been working on their design in-house since 2000 and are more than satisfied with their strength and safety levels. Their main source of strength originates from the carbon fibre shell.
How is hydrogen collected for hydrogen fuel cells?
Hydrogen can be produced from many different sources in different ways to use as a fuel. The two most common methods for producing hydrogen are steam-methane reforming and electrolysis (splitting water with electricity). Researchers are exploring other hydrogen production methods, or pathways.
Why is hydrogen storage so difficult?
Hydrogen is explosively flammable, ignites much faster than any other hydrocarbon fuel. For this reason, hydrogen is extremely hard to handle, can't be stored for extended periods of time without A, boiling off or B, reacting with the surface material trying to contain.
Is it better to store hydrogen as a liquid or gas?
Selecting the right hydrogen storage method depends on your specific applications, transportation needs, and operational scale. While gaseous hydrogen storage offers simplicity for small-scale projects, liquid hydrogen's higher energy density and cost efficiency make it ideal for larger, long-distance operations.
How is hydrogen stored in a fuel cell?
Hydrogen has high energy content by weight (density) but not by volume, which is a challenge for storage. In order to store sufficient quantities of hydrogen gas, it is compressed and stored at high pressures.
What happens if a hydrogen fuel cell car crashes?
The fuel cell itself does have a small inventory of hydrogen. In a crash, the fuel cell could easily be crushed and the hydrogen could cross the membrane. The fuel cell probably cannot be designed to contain the resulting pressure, so it will be necessary to safely vent any products.
What happens to hydrogen in hydrogen fuel cells?
Hydrogen fuel cells produce electricity by combining hydrogen and oxygen atoms. The hydrogen reacts with oxygen across an electrochemical cell—similar to a battery—to produce electricity, water, and small amounts of heat.
How long does a tank of hydrogen last on a Toyota Mirai?
The Mirai refueling takes between 3 and 5 minutes, and Toyota expected a total range of 480 km (300 miles) on a full tank.
What is the biggest disadvantage of hydrogen fuel cells?
Disadvantages:
- Expensive to manufacture due the high cost of catalysts (platinum)
- Lack of infrastructure to support the distribution of hydrogen.
- A lot of the currently available fuel cell technology is in the prototype stage and not yet validated.
- Hydrogen is expensive to produce and not widely available. Privacy.
What is a disadvantage of hydrogen fuel cells?
Expensive to manufacture due the high cost of catalysts (platinum) Lack of infrastructure to support the distribution of hydrogen. A lot of the currently available fuel cell technology is in the prototype stage and not yet validated. Hydrogen is expensive to produce and not widely available.
