Innovative Fuel Cell Paves Way for Electric-Powered Aircraft Flights
MIT Researchers Propose Sodium Metal Fuel Cell as Solution for High-Power Transportation
Boston, Massachusetts - Electrifying airplanes, trains, and ships has remained a challenge due to the limited energy storage capabilities of current batteries. However, a team of researchers led by MIT has proposed a solution that could change the game: a sodium metal fuel cell.
Unlike traditional batteries, the new fuel cell can be quickly refueled rather than recharged, making it more practical for transportation systems that require high power and quick turnaround time. The fuel for this cell is an inexpensive and widely available commodity, liquid sodium metal, while the oxidizer is ordinary air.
The cell consists of a solid ceramic material serving as the electrolyte, allowing sodium ions to pass freely, and a porous air-facing electrode that facilitates the chemical reaction between sodium and oxygen, producing electricity. In a series of experiments with a prototype device, researchers demonstrated that the cell carried more than three times the energy per unit of weight of lithium-ion batteries commonly used in electric vehicles today.
The findings, published in Joule, reveal that such a technology could be revolutionary for aviation, where weight is especially crucial. The improvement in energy density could potentially make electrically powered flight practical at a significant scale, as it would bring the energy density closer to the needed 1,000 watt-hours per kilogram for realistic electric aviation.
"People will undoubtedly think this is a totally crazy idea," said Yet-Ming Chiang, Kyocera Professor of Ceramics at MIT. "但如果他们不这么想，那么我会感忧一下，因为如果人们不从一开始就觉得这有点太野蛮，那么显然它不会如此革命性。"
The technology could also have applications in marine and rail transportation, as both sectors require very high energy density at low cost. Researchers have already formed a company, Propel Aero, to develop the technology, which is currently housed at MIT's startup incubator, The Engine.
One of the advantages of this fuel cell is its inherent safety compared to other high-energy density batteries. Sodium metal, while highly reactive, can be better managed than lithium due to its flammable nature. If exposed to moisture, sodium can spontaneously ignite, but this fuel cell design reduces the risk of runaway reactions through the use of air as one of the reactants.
While the device currently exists only as a small, single-cell prototype, researchers expect it to be straightforward to scale up for commercialization. Ethan Friesen, an MIT summer intern who attended Desert Mountain High School in Scottsdale, Arizona, contributed to the research.
In time, the team envisions producing a brick-sized fuel cell delivering around 1,000 watt-hours of energy, enough to power a large drone. A demonstration of this technology is expected within the next year.
The research team also included Alden Friesen, Kailash Raman and William Woodford of Form Energy in Somerville, Massachusetts; Shashank Sripad of And Battery Aero in California; Venkatasubramanian Viswanathan of the University of Michigan; and MIT doctoral students Karen Sugano, Sunil Mair, and Saahir Ganti-Agrawal. The work was supported by ARPA-E, Breakthrough Energy Ventures, and the National Science Foundation, and used facilities at MIT.nano.
- The sodium metal fuel cell proposed by MIT researchers could revolutionize transportation systems, particularly those requiring high power and quick turnaround times.
- The fuel for this cell is liquid sodium metal, an inexpensive and widely available commodity, while the oxidizer is ordinary air.
- In experiments with a prototype device, the sodium metal fuel cell carried more than three times the energy per unit of weight of lithium-ion batteries commonly used in electric vehicles today.
- The improvement in energy density could make electrically powered flight practical at a significant scale, bringing the energy density closer to the needed 1,000 watt-hours per kilogram for realistic electric aviation.
- The technology has potential applications in marine and rail transportation, due to its high energy density and low cost.
- Researchers have formed a company, Propel Aero, to develop the technology, which is currently housed at MIT's startup incubator, The Engine.
- One of the advantages of this fuel cell is its inherent safety compared to other high-energy density batteries, as it reduces the risk of runaway reactions through the use of air as one of the reactants.
- The research team consists of students from various institutions, including MIT, Form Energy, And Battery Aero, and the University of Michigan.
- The team expects to demonstrate the technology in the form of a brick-sized fuel cell delivering around 1,000 watt-hours of energy, enough to power a large drone, within the next year.
