Materials Science & Energy
In a laboratory at the Max Planck Institute for Chemistry, researchers squeeze a sample of hydrogen sulfide between two diamonds. The pressure reaches 1.7 million times atmospheric pressure, comparable to conditions near the Earth's core. At this pressure, and cooled to minus seventy degrees Celsius, the hydrogen sulfide becomes a superconductor, conducting electricity with zero resistance. For the first time, scientists directly measure the superconducting gap, the energy barrier that keeps electron pairs bound together, resolving a mystery that has puzzled physicists for nearly a decade.
Six thousand kilometers away, in Fujian province in southeastern China, the battery manufacturer CATL begins mass production of its second-generation sodium-ion batteries. These cells achieve one hundred and seventy-five watt-hours per kilogram and last for over ten thousand charge-discharge cycles. The factory's annual capacity is thirty gigawatt-hours, enough to store the output of several nuclear power plants.
These two developments, occurring in the same year, represent different timescales of technological progress. Superconductivity research has been advancing incrementally for over a century, approaching a goal that remains tantalizingly out of reach. Battery technology has advanced rapidly in the past decade, reaching commercial viability for applications that seemed impossible a generation ago. Together, they point toward an energy infrastructure fundamentally different from what we have today.
The Superconductor Breakthroughs
The December 2025 announcement from the Max Planck Institute represents a culmination of research that began in 2015. That year, Mikhail Eremets and his team discovered that hydrogen sulfide, compressed to extreme pressures, becomes superconducting at temperatures far higher than any previously known material. The critical temperature, the point below which superconductivity occurs, was two hundred and three degrees above absolute zero, or minus seventy degrees Celsius. This was warmer than the boiling point of liquid nitrogen and far warmer than the few degrees above absolute zero required by most superconducting materials.
The discovery opened a new field of research. Subsequent work explored other hydrogen-rich compounds. Lanthanum decahydride achieved superconductivity at two hundred and fifty degrees above absolute zero, roughly minus twenty-three degrees Celsius. Yttrium hydride reached similar temperatures. These materials are called superhydrides because hydrogen atoms pack tightly into their crystal structures, creating conditions favorable for superconductivity.
The challenge was understanding why these materials work so well. Superconductivity involves electrons pairing up into what physicists call Cooper pairs. In conventional superconductors, the pairing is mediated by vibrations in the crystal lattice, called phonons. The electrons interact with these vibrations in a way that allows them to overcome their natural repulsion and pair together. The paired electrons then flow through the material without resistance.
Measuring the properties of superhydrides has been extraordinarily difficult because the samples are tiny and exist only under extreme pressure. The entire sample chamber might be smaller than a grain of sand. Standard techniques for probing superconductors do not work under these conditions.
The December breakthrough solved this problem. Researchers developed a new tunneling spectroscopy technique that operates under high pressure. They could directly probe the energy gap between the superconducting state and the normal state, confirming the mechanism by which superhydrides achieve their high critical temperatures. This is not merely academic knowledge. Understanding the mechanism provides guidance for searching for new materials, potentially ones that work at lower pressures or higher temperatures.
Mikhail Eremets, who led this research program for a decade, passed away in November 2024. He did not live to see the final results, but his collaborators dedicated the work to his memory. In the field of superconductivity research, the December paper represents the most important advance since the original 2015 discovery.
Topological Superconductors
A different kind of superconductivity research made headlines in 2025 with the discovery of a new topological superconductor, platinum bismuth two. This material behaves differently from conventional superconductors. Only its surfaces become superconducting; the interior remains a normal metal. The edges of these superconducting surfaces host exotic particles called Majorana fermions, which have potential applications in quantum computing.
Topological superconductors are interesting for reasons beyond their immediate applications. They demonstrate that superconductivity can arise from the geometry of a material's electronic structure rather than from the conventional phonon-mediated mechanism. This opens possibilities for room-temperature superconductivity through entirely different pathways than the hydride research.
The platinum bismuth two discovery came from a collaboration between several research groups studying the surfaces of this compound with advanced spectroscopic techniques. The material is unusual in that its superconductivity is protected by topology, a mathematical property that describes how surfaces connect to each other. This protection makes the superconducting state more robust against disturbances, which could be valuable for practical applications.
Nickelate Superconductors
At the SLAC National Accelerator Laboratory in California, researchers achieved another milestone in 2025 by stabilizing nickelate superconductors at room pressure. Nickelates are compounds containing nickel and oxygen that had been predicted to superconduct since the 1990s. Achieving superconductivity in these materials proved far more difficult than expected. The compounds are unstable and difficult to synthesize. Previous nickelate superconductors required special substrates and careful growth conditions.
The SLAC work demonstrated that nickelate superconductors could be produced and maintained under ordinary laboratory conditions, removing a barrier to further research. The critical temperatures of nickelates remain relatively low, but they represent a new family of high-temperature superconductors distinct from both the copper oxide ceramics discovered in the 1980s and the hydrides discovered in the 2010s.
Having multiple families of high-temperature superconductors helps researchers identify the common factors that enable superconductivity at elevated temperatures. Each family has different chemistry and different crystal structures, but they share certain electronic properties. Understanding what they have in common may point toward materials with even higher critical temperatures.
Theoretical Advances
Alongside experimental discoveries, theoretical understanding of superconductivity advanced in 2025. Scientists at Penn State developed a new framework called zentropy theory that bridges classical and quantum descriptions of superconductivity. The theory allows researchers to predict which materials might become superconducting without having to synthesize and test them first.
The idea of computational materials discovery is not new. The Materials Project, a database of computed material properties, has catalogued over one hundred and fifty thousand compounds. What zentropy theory adds is a specific framework for predicting superconductivity, which has been difficult to compute accurately. The approach uses thermodynamic principles to estimate the conditions under which superconductivity might emerge.
Separate theoretical work during 2025 established that room-temperature superconductivity is possible within the laws of physics, with critical temperatures potentially linked to fundamental constants like electron mass and Planck's constant. This does not guarantee that practical room-temperature superconductors exist, but it eliminates the possibility that some fundamental physical law prohibits them.
Sodium-Ion Battery Commercialization
While superconductor research advances incrementally toward distant goals, battery technology is crossing commercial thresholds that enable immediate applications. The most significant development in 2025 was the mass production of sodium-ion batteries at scale.
In April 2025, CATL launched its sodium-ion battery brand called Naxtra. The name combines sodium's chemical symbol, Na, with extra to suggest extended performance. The batteries achieve an energy density of one hundred and seventy-five watt-hours per kilogram, approaching the one hundred and eighty-five watt-hours per kilogram typical of lithium iron phosphate batteries. More remarkably, the cycle life exceeds ten thousand charges, with some prototypes reaching twenty thousand cycles while retaining seventy percent of initial capacity.
The practical implications are significant. A battery that lasts for ten thousand cycles at daily use would operate for over twenty-seven years. Even accounting for calendar aging, which degrades batteries regardless of use, CATL projects a service life of twenty-five years under normal conditions. This is two to three times the lifespan of current lithium-ion batteries.
Sodium-ion batteries also operate over a wider temperature range than lithium-ion. The Naxtra cells retain ninety-three percent of capacity at minus thirty degrees Celsius and function down to minus forty degrees without supplemental heating. This makes them suitable for grid storage in cold climates where lithium batteries struggle.
Cost is the other major advantage. Sodium is roughly one thousand times more abundant than lithium in the Earth's crust. It is present in seawater and common salt deposits. The manufacturing processes for sodium-ion batteries are similar to those for lithium-ion, allowing factories to be converted rather than built from scratch. CATL projects costs below thirty dollars per kilowatt-hour at scale, compared to roughly one hundred dollars per kilowatt-hour for current lithium-ion cells.
The Chinese Manufacturing Lead
Both CATL and BYD, the two largest battery manufacturers in the world, are Chinese companies. Together they hold over fifty percent of the global electric vehicle battery market, producing eight hundred and twelve gigawatt-hours of batteries during the first nine months of 2025. CATL alone commands roughly thirty-eight percent of the market.
This concentration reflects deliberate industrial policy. China identified battery manufacturing as a strategic priority over a decade ago. The government provided subsidies, protected domestic markets, and coordinated investments across the supply chain from raw materials to finished cells. The result is a manufacturing ecosystem that competitors have struggled to replicate.
BYD began construction of a thirty gigawatt-hour sodium-ion factory in January 2024. CATL's production facility in Fujian province has similar capacity. By 2030, Chinese manufacturers are expected to produce over ninety percent of global sodium-ion battery output. The industry projections suggest Chinese sodium-ion capacity will grow from ten gigawatt-hours in 2025 to nearly three hundred gigawatt-hours by 2034.
Western attempts to develop competing sodium-ion industries have largely failed. Natron Energy, an American startup that had announced plans for a fourteen gigawatt-hour factory in North Carolina, collapsed in September 2025. The company struggled to match Chinese costs and could not secure sufficient capital to reach commercial scale. Similar stories have played out across the battery industry, where Western startups develop promising technology but fail to translate it into manufacturing.
Grid Storage Applications
The primary market for sodium-ion batteries is stationary storage rather than vehicles. Their lower energy density makes them less suitable for electric cars, where weight and volume matter. But for grid storage, where the batteries can be as large as needed, energy density matters less than cost and longevity.
By 2026, forecasters predict that seventy percent of sodium-ion batteries will be used for energy storage supporting electrical grids. These installations balance fluctuations in renewable generation, storing electricity when the sun shines or wind blows and releasing it during calm nights. The ability to cycle daily for twenty-five years makes sodium-ion batteries economically viable for applications where lithium-ion replacement costs would be prohibitive.
Grid storage is growing rapidly. The China Energy Storage Alliance recorded forty-eight sodium-ion production projects planned in 2024 with combined capacity of two hundred and fifty-five gigawatt-hours. During 2025, investment recovered from a slowdown, with thirty-seven new projects totaling one hundred and eighty gigawatt-hours announced. This pace of expansion would make sodium-ion a significant component of grid infrastructure within a decade.
The combination of low cost, long life, and temperature tolerance positions sodium-ion batteries as the default choice for many storage applications. Lithium-ion will likely remain dominant for vehicles and portable electronics, where its higher energy density justifies the higher cost. But for stationary storage, sodium may become the new standard.
The Research Pipeline
Academic research in battery technology continues to produce improvements. Solid-state batteries, which replace the liquid electrolyte of conventional cells with a solid material, promise higher energy density and improved safety. Several companies are developing solid-state lithium batteries for electric vehicles, with commercial introduction expected in the late 2020s.
Lithium-sulfur batteries offer theoretical energy densities far above current lithium-ion chemistry. The challenge is cycle life: sulfur compounds tend to dissolve into the electrolyte over repeated charging, degrading capacity quickly. Researchers have made progress in stabilizing these reactions, but commercial lithium-sulfur cells remain years away.
Sodium-ion research itself continues. The Naxtra cells represent second-generation technology. CATL has already announced plans for next-generation sodium-ion batteries with higher energy density, targeting ranges of five hundred kilometers for electric vehicles. Whether sodium-ion can ever match lithium-ion for energy-intensive applications remains to be seen, but the performance gap is narrowing.
The Materials Project and Computational Discovery
Behind both superconductor and battery research lies a growing capability for computational materials discovery. The Materials Project, hosted at Lawrence Berkeley National Laboratory, provides computed properties for over one hundred and fifty thousand materials. Researchers can search this database for compounds with desired characteristics, screening thousands of candidates before synthesizing any in the laboratory.
Machine learning has accelerated this process. Models trained on known materials can predict properties of hypothetical compounds. The same techniques that enabled AlphaFold to predict protein structures are being applied to crystal structures and electronic properties. The design-build-test-learn cycle that transformed software development is now transforming materials science.
For superconductors, computational methods can predict which compounds might have high critical temperatures without requiring the extreme pressures and low temperatures of experimental testing. For batteries, they can identify candidate electrode materials and electrolytes with favorable properties. This does not eliminate the need for experimental validation, but it focuses experimental effort on the most promising candidates.
Where to Find the Research
Materials science research appears across multiple publications. For superconductivity, the preprint archive arXiv hosts the latest findings in the condensed matter superconductivity section. The journals Nature, Science, and Physical Review Letters publish major discoveries. The Journal of Superconductivity and Novel Magnetism covers the field specifically.
Battery research appears in journals including Advanced Energy Materials, Nature Energy, and the Journal of the Electrochemical Society. Industry analysis comes from BloombergNEF, which tracks battery manufacturing and costs, and from organizations like the China Energy Storage Alliance, which monitors the Chinese market.
The Materials Project provides open access to its computed database at materialsproject.org. Researchers can search for compounds by formula, structure, or property. The database includes not only thermodynamic properties but also electronic band structures, which are relevant for both superconductivity and battery applications.
The Open Science of Materials
Materials science has a strong tradition of open publication, reflecting both the nature of the field and the sources of its funding. Most fundamental research is conducted at universities and national laboratories with public support. Publication norms emphasize reproducibility, with papers typically including detailed experimental methods and characterization data.
The Materials Project exemplifies this openness. Funded by the Department of Energy, it makes computed data freely available to any researcher. Companies use this data to guide their internal research, reducing duplication of computational effort. Academic groups build on each other's published results, accelerating progress through collaboration.
Industry research is more guarded, particularly for battery manufacturing where process knowledge confers competitive advantage. CATL and BYD do not publish detailed specifications of their cell chemistry or manufacturing processes. But the underlying science, the electrode materials and electrolyte compositions that enable sodium-ion batteries, is well documented in academic literature. The gap between academic knowledge and commercial products is narrowing as manufacturing scales up.
What 2025 Means
The materials science advances of 2025 represent different kinds of progress. Superconductivity research achieved a fundamental understanding that may guide future discoveries. Sodium-ion batteries crossed commercial thresholds that enable immediate deployment. Both point toward an energy infrastructure transformed by materials that did not exist a generation ago.
The superconductor breakthroughs are not yet commercially relevant. Room-temperature superconductivity at atmospheric pressure remains a goal rather than an achievement. The hydride superconductors work only under pressures that can be produced only in tiny laboratory samples. But understanding why they work brings practical materials closer. The trajectory from laboratory discovery to commercial application typically takes decades in materials science. The 2025 results suggest that trajectory may be accelerating.
Sodium-ion batteries are commercially relevant now. The factories are built. The products are shipping. The economic equations for grid storage are changing as costs fall and lifespans extend. What was speculative five years ago is infrastructure being deployed today.
Together, these developments suggest that the constraints of physics are less limiting than often assumed. Room-temperature superconductivity is possible in principle; the challenge is finding materials that achieve it under practical conditions. Long-lasting, cheap batteries exist today; the challenge is scaling production to meet demand. The problems that remain are engineering problems, not fundamental barriers. That distinction matters for how we think about the future of energy.