Natrium‑ilma polttokennot tuovat akkuilmaliikenteen lähemmäs todellisuutta

Researchers from MIT and other lending institutions unveiled a sodium-air fuel cell design capable of powering aircraft. The revolutionary concept provides higher energy density while naturally capturing atmospheric carbon dioxide. Here’s how sodium-air fuel cells could revolutionize air travel in the years to come.

Akkukysymykset ilmailussa

While EVs continue to become the norm, the aviation sector hasn’t seen such growth. There are some options, yet they are a personal craft, limited to only a few passengers. The primary reason for this lack of growth is that battery technology has not yet met the criteria necessary to power commercial airliners. Today’s lithium-ion batteries are heavy, and the amount needed to power an airliner requires too many cells to work.

Tehoaukko sähköisessä ilmailussa

To achieve battery-powered flight, engineers need to take the current electric vehicle’s lithium-ion batteries from 300 watt-hours per kilogram, all the way up to 1,000 watt-hours per kilogram. Tripling the power density of lithium-ion batteries isn’t possible, but other options have begun to emerge.

Metalli‑ilma akut: Korkea energia, alhainen uudelleenlatauskyky

Metal-air batteries like lithium-air or sodium-air have been researched thoroughly over the last few decades. They do possess more density, but they also have some serious issues in regards to recharging. The chemical reaction of alkali metal-air batteries results in the formation of solid discharge products, which are difficult to remove, making the units obsolete after only a few cycles. Thankfully, this scenario could change.

Natrium‑ilma polttokennon läpimurto

MIT researchers, alongside scientists from different institutions, have introduced a sodium-metal fuel cell technology that could help alleviate previous issues and usher in a new era in clean portable energy.

The study Sodium-air fuel cell for high energy density and low-cost electric power, published in the journal Joule, delves into a specially designed liquid sodium metal-air fuel cell. The fuel cell integrates a solid electrolyte membrane that allows the battery to adjust the humidity and air stream to enhance performance.

Miten natrium‑ilma polttokennot eroavat perinteisistä akuista

A fuel cell operates like a battery, with the main difference being that the energy-producing material is swapped out. This design is ideal for travel because it eliminates the need to recharge. Instead, the batteries are refueled.

The old electrode is then sent to the factory to be processed, refilled, and sent back out for re-use. In this instance, sodium is used. It has a low melting point of 98 degrees Celsius, making it ideal for low-cost refueling.

Natrium‑ilma polttokennon sisäinen suunnittelu

The sodium-air fuel cell uses common and inexpensive liquid sodium metal located on one side of the unit. On the other side is a chamber of open air. Between the two layers is an electrolyte. The electrolyte has a porous structure on the air-facing side, which allows sodium ions to pass freely and react with the O2, creating electricity.

Prototyypit ja polttokennikasetin suunnittelu

The engineers created two testable prototypes. Both versions used the same approach to produce the energy. However, one was designed to sit horizontally. Both utilized a rechargeable cartridge that was filled with liquid sodium metal and then sealed.

Lähde – Joule

H-solun suunnittelu: miten se toimii

The H-cell prototype resembled the letter H with two vertical glass tubes connected by a solid electrolyte-filled tube in the middle. The center tube uses a ceramic electrolyte material and a porous air electrode to create an electrochemical reaction between the liquid sodium metal and the oxygen, consuming the sodium fuel. The second design is similar to the H, but the base was altered. This setup uses a tray of the electrolyte material that sits over a porous air electrode.

Kiinnostavaa on, että näiden reaktioiden sivutuote yhdistyy ympäröivän ilman kanssa muodostaen natriumkarbonaattia. Useiden muiden luonnollisesti tapahtuvien kemiallisten reaktioiden kautta päästöt muuttuvat natriumbikarbonaatiksi, joka on myös …

Tämä natriumbikarbonaatti on ympäristölle hyödyllinen. Kun sitä lisätään valtameriin, se voi auttaa neutraloimaan veden happamuutta, lisäten toisen kerroksen puhdistustehoa polttokennin suunnitteluun.

Kosteuden rooli polttokennin tehokkuudessa

One key discovery that researchers were surprised to learn was the overall effect of moisture in the process. The engineers observed that the amount of humidity in the air had a major impact on the electrochemical reaction.

They noted that humidity was helpful in that it created sodium discharge in liquid form. This discovery allowed them to eliminate solid battery waste, which is much harder to remove for refilling purposes. The liquid residue could be easily pushed out using pressurized air, lowering costs.

Finnish translation:
Yksi keskeinen löytö, joka yllätti tutkijat, oli kosteuden kokonaisvaikutus prosessiin. Insinöörit havaitsivat, että ilman kosteuden määrä vaikutti merkittävästi elektrokemialliseen reaktioon.

He totesivat, että kosteus oli hyödyllistä, koska se loi natriumin purkautumisen nestemäisessä muodossa. Tämä löytö mahdollisti kiinteän akkujätteen poistamisen, mikä on paljon vaikeampaa täyttötarkoituksiin. Nestemäisen jäännöksen voi helposti poistaa paineilmaa käyttäen, mikä alentaa kustannuksia.

Natrium‑ilma polttokennin testaus

The engineers conducted several tests to check their theories. They used precise air streams and controlled humidity to see different approaches and optimize performance. Their test results were eye‑opening, with the new fuel cell design outperforming all previous battery designs.

Tulokset: 3‑kertainen energiateho litium‑ioniin verrattuna

The engineers were excited to see their creation outperform traditional batteries by over 3x. They registered stack‑level energy density to 1,200 Wh/kg at 80 mA/cm2.  This performance only required a 2.3‑cm thickness of sodium metal to sustain continuous operation.

Natrium‑ilma polttokennojen hyödyt

Many benefits make sodium‑air batteries a strong contender for future applications. For one, they have much lower costs. Lithium‑ion batteries are expensive to manufacture and are heavy. Plus, they leave lots of waste. The use of sodium metal is far cheaper. Additionally, the US has a history of mass producing this material as it is used as an additive in tetra‑ethyl lead.

Energiatiheyden edut

The sodium‑air battery offers 3x the weight‑to power ratio of traditional lithium‑ion setups . This added power density opens the door for their use in weight‑sensitive applications . The added energy means that batteries can be made smaller and more form‑fitting to meet the needs of future designers.

Parannettu turvallisuus litium‑ioniin verrattuna

Another benefit of sodium‑air batteries is that they are much safer than lithium‑ion batteries. The internet has lots of stories of lithium‑ion batteries catch and explode due to thermal runaway. Sodium air batteries have far less risk of thermal runaway, main because one side is only filled with air versus two reactants, like in other designs.

Ympäristöedut ja ilman puhdistavat sivutuotteet

One of the main benefits of sodium-air batteries is that they are much cleaner. Their by-product naturally chemically reacts with pollutants and converts them to helpful chemicals. This approach is more sustainable than lithium-ion batteries, which are already creating landfill concerns as they age.

Käytännön sovellukset ja kaupallistumisaikataulu

There are several uses for sodium-air batteries. These batteries provide high energy density at a low cost. Their lightweight design makes them ideal for use in commercial truck applications ranging from freight trucking to trains, boats, and aviation.

Ilmailu: Natrium‑ilma polttokennojen keskeinen kohde

Sodium-air batteries could help usher in the age of electric Aircraft. These devices could utilize replaceable fuel cell trays to help power global trips and more. The engineers described a concept where the byproduct of the fuel cells exits the plane through its traditional exhaust, allowing the craft to clean the air as it travels.

Aikataulu ja kaupallinen näkymä

The researchers are keen to get this technology into the commercial sector as fast as possible. They have already created a company called Propel Aero to help secure funding to take the concept to market. According to the engineers, their goal is to produce a brick-sized fuel cell capable of delivering a reliable 1,000 watt-hours of energy to large commercial drones.

Natrium‑ilma polttokennin tutkijat

The sodium-air fuel cell study was put forth by Karen Sugano, Sunil Mair,  Saahir Ganti-Agrawal, Yet-Ming Chiang, Alden Friesen, Kailash Raman, William Woodford, Shashank Sripad, and Venkatasubramanian Viswanathan.  The project received financial support from Breakthrough Energy Ventures,  the National Science Foundation, and ARPA-E.

Sijoittaminen akkuteknologian alaan

There is a race to bring the world better batteries, and manufacturers continue to step up to the plate with new solutions. The world is wireless, and batteries are their replacements. As such, battery technology has become one of the fastest innovative technologies. Here’s one company leading that charge.

Enovix Corp.

Enovix Corp (ENVX ) entered the market in 2006 and is headquartered in Fremont, California. The company’s founders, Harold Jones Rust III, Ashok Lahiri, and Murali Ramasubramanian, wanted to create a more efficient lithium-ion battery to power EVs and other advanced technologies. Since its launch, Enovix has remained a pioneering spirit.

The company has helped to push 3D silicon lithium-ion rechargeable battery architecture as a better alternative to the status quo. Additionally, the firm is exploring new materials and manufacturing processes, intending to lower costs and improve the performance of lithium-ion options.

Enovix is positioned for success in the market. The company has seen significant growth powered by its commitment to creating environmentally friendly, energy-efficient, high-performance lithium-ion battery alternatives.

Uusimmat Enovix Corp. (ENVX) osakeuutiset ja kehitys

Puhdas tulevaisuus natrium‑ilma polttokennojen voimalla

The concept of using a battery that releases a byproduct that cleans the air is a major game-changer. This technology could help to solve multiple problems, ranging from battery density to cleaning oceans. Its impact will be felt for years if the project succeeds in its goal to revolutionize portable power. For now, a salute to the team on their efforts and desire to make the world greener.

Tutustu muihin hienoihin energialöytöihin täällä.

Viitatut tutkimukset:

^{1. Sugano, K., Mair, S., Ganti-Agrawal, S., Chiang, Y.-M., Friesen, A., Raman, K., Woodford, W., Sripad, S., & Viswanathan, V. (2025). Natrium‑ilma polttokenni korkean energiatehon ja alhaisen kustannuksen sähkövirtaan. Joule. https://doi.org/10.1016/j.joule.2025.101962}