Committee

The rise of the lithium-ion battery, which powers everything from the smallest personal electronics to gargantuan energy storage systems, has been nothing short of revolutionary. But as anyone who’s boarded a plane in the last decade could tell you, storing and pumping out energy by moving charged lithium ions through a liquid electrolyte soup has its drawbacks, not least that the batteries have a troubling tendency to catch fire. Enter the solid-state battery, which swaps liquid for a solid ceramic or polymer, creating power packs that charge faster, last longer, cram more energy into smaller spaces, and (crucially) run cooler. A new generation of companies aim to bring such batteries to market, and if their bets pan out, the tech could substantially ease the shift away from fossil fuels.  The sticking points Solid-state batteries have been “just a few years away” for more than a decade now. In laboratories, the technology works. But there have been challenges. In designs that pair the solid electrolyte with a lithium-metal anode (the side of the battery that releases electrons into an electrical circuit), needlelike filaments called dendrites tend to grow during charging, and they eventually push through the electrolyte and short the cell. Solid electrolytes are supposed to physically block the formation of dendrites, but many of them crack as the treelike projections break through like roots in a concrete foundation.  Then there’s the problem of manufacturing at scale. Mass production requires large quantities of defect-free sheets of ceramic-like material to make the electrolytes as well as dry rooms for assembly, since those electrolytes have a tendency to react with water. Would-be manufacturers quote a range of potential prices for solid-state batteries, but most expect them to fall in line with lithium-ion packs sometime in the mid-2030s.  The progress Nascent as the technology is, solid-state batteries have already seen high-­profile missteps. But one of America’s most advanced solid-state-battery companies says it’s closing in on being able to bring its product to market. The Bill Gates–backed QuantumScape launched in Silicon Valley in 2010 and built its battery around a class of ceramic materials that it says is compatible with lithium—meaning no dendrite formation. “We spent, then, like 10 years learning how to process it to satisfy all of the other requirements,” says Tim Holme, QuantumScape’s cofounder and chief technology officer. In 2025, the startup announced a proprietary, large-scale manufacturing method for quickly producing and heat-treating the ceramic electrolytes used in its batteries. “Nobody has ever done this in the field of ceramics before,” Holme claims. For 10,000 years, producing ceramics has involved slowly cooking the starting materials in an oven over the course of days. “We figured out a way to shorten that down to several minutes,” he says.  Plenty of other companies are pushing the tech forward as well. Toyota, the world’s biggest automaker, launched a research program on solid-state batteries way back in 2010. It’s now partnering with the global energy and petroleum company Idemitsu Kosan on a pilot plant, promising cars that can travel up to 745 miles after charging 10 minutes or less—a huge leap, if it works out. In China, CATL, the giant behind roughly 40% of the global battery market, is aggressively pursuing solid-state batteries too, pumping nearly $2.6 billion into a research program in 2024 alone. Mercedes, meanwhile, equipped one of its EQS sedans with solid-state batteries last fall; after driving nonstop for 750 miles, the car still had some range to spare.  Will the tech gain traction? Investing in vehicle batteries makes sense given the size of the potential market. But any little uptick in cost typically gets passed on to buyers, so the first solid-state EV batteries will inevitably be more expensive.  Grid storage buyers, who are working to meet the increasing demands posed by data centers, may also hesitate to purchase new technologies that still haven’t come down the cost curve. Then again, the promise of energy storage that lasts longer than lithium-­ion’s typical eight hours could make them easier to persuade.  Some companies are taking a page from a playbook employed by outfits pursuing fusion: Focus on near-term markets with better margins to help fund development and bring down costs. Solid-state firms including California-based Solid Energies and Arizona-headquartered Sion Power are looking at selling batteries to the aviation industry or the military. “Those are sectors that are less sensitive to cost, and they typically require lower volumes as well,” says Evelina Stoikou, head analyst for battery technologies and supply chains at the consultancy BloombergNEF. “It’s a good way to prove your concept, then go through and fund the pilot plant where you can make that and eventually scale up.” Progress meter ………… 7 The technology works, the capital is there, and demand is not far behind. But as with anything in manufacturing, unknown unknowns remain. 

Scrubbing Earth of per- and polyfluoroalkyl substances—a.k.a. PFAS or forever chemicals—could eliminate a list of woes for people and planet. Used for decades in everything from nonstick pans to firefighting foams, PFAS have been linked to increased risks of fertility challenges, developmental delays, cancer, and reduced immune response. They are known for a strong bond between carbon and fluorine, which the environment struggles to break down.  The sticking points PFAS are everywhere: They spew from factories and slough off products and into water with normal use. Scientists have found them in everything from human blood to Antarctic snow. One 2022 report found that 89% of the US population had PFAS in excess of two nanograms per milliliter of blood plasma, a common threshold for potential adverse health effects, and 9% of the population had passed the riskier level of 20 nanograms per milliliter. The PFAS monster is also a moving target. New compounds are still being created and used. There are more than 12,000 of them, and much of the cleanup research focuses on only a small handful.  The progress Cleansing PFAS-contaminated soil is a project in its infancy, but it is possible to prevent more buildup by pulling the chemicals out of water systems. There are two ways to handle this: trap or destroy. Some scientists have found reverse osmosis—a process that pushes water through supertight filters—useful in point-of-use cases, like water filters at kitchen sinks.  Other techniques in the pipeline might be more suitable for large-scale removal—for example, at water treatment facilities. One, called foam fractionation, generates bubbles that capture PFAS. More approaches, like ensnaring the chemicals in nanothin layers of charged metal, are also under investigation.  Trapping, though, is imperfect. You’re left with PFAS-filled brine, which if not properly destroyed (an expensive and energy-sucking endeavor) can still end up in the environment.  Jack Huang, a professor of crop and soil sciences at the University of Georgia, is working on destruction. He’s testing a method called electrochemical degradation, which uses electrodes to break down the bonds that hold PFAS together. The product destroyed more than 90% of PFAS mass in tests and has already been licensed by the engineering consulting firm AECOM.  Ridding life of PFAS is also a policy challenge. There are alternatives; we just need the push to use them. And we’ve had success before: The EPA’s 2010/2015 PFOA Stewardship Program has helped slash the release of water-repellent perfluorooctanoic acid by 95%. More recently, Minnesota, Maine, and New Mexico have passed bans on PFAS in products like cookware and dental floss.  Progress meter ………… 6 Scientists are making strides toward removing and destroying PFAS—but it’ll be all for naught if we don’t turn off the tap. 

Every year, traffic crashes kill more than one million people, and they’re the leading cause of death for children and young adults. In the US, 100 people a day lose their lives this way, in many cases not on highways but on rural and local streets. “Traffic deaths are a leading cause of preventable death, yet we treat it like it’s inevitable,” says Leah Shahum, founder and director of the Vision Zero Network, a nonprofit focused on making streets less deadly.  The sticking points The causes of a crash can be muddy. Drivers make mistakes like speeding or getting distracted, but infrastructure fails them too: Perhaps they were on a road built for speed and not safety, in a screen-filled vehicle, or at an intersection where pedestrians, cyclists, and other cars aren’t visible.  Cheap and proven traffic-calming opportunities abound—from using planters to tighten intersections to lowering speed limits—but government logjams and red tape can be speed bumps. “There’s so many moving parts,” says Laura Sandt of the University of North Carolina Highway Safety Research Center. “On the flip side, it shows that we have so many opportunities for injury prevention.”  The progress The total number of traffic deaths has increased over the last century. And though the US rate has dipped from a peak of 30.8 deaths per 100,000 people in the 1930s, the past decade has seen a concerning jump in deadly pedestrian incidents. At the same time, communities are waking up to the essential role of traffic safety policy, Shahum says.  One success story is Hoboken, New Jersey, which hasn’t had a traffic fatality since 2017. This is due to a combination of efforts like boosting investment in public transit, promoting walkability by extending curbs, and using cameras to identify crash-prone intersections in need of a redesign. But even there, obstacles remain. If an intersection hasn’t been proved to be deadly, for example, it can be an uphill battle to argue for removing parking spaces to widen curbs. “You’re kind of selling insurance through these improvements, and that’s not always easy,” says Greg Francese, the city’s acting director of transportation and parking. There’s also no silver bullet that will work everywhere. Situated directly across the river from New York City, Hoboken is a highly transit-oriented city of less than 60,000 people. Success there might not translate to traffic-death hot spots like Memphis or Dallas. But it’s not impossible. Take Edmonton, Alberta, a sprawling, car-centric Canadian city of around one million people: Between 2015 and 2020, it cut traffic fatalities by 63% and serious injuries by 40% by adjusting speed limits and improving signals at crosswalks.  Progress meter ………… 6 We know how to tweak intersections and adjust traffic signals. Getting the funding and will to roll out those changes is the big red light. 

In this article, you will learn how to build a multi-modal RAG pipeline in Python that retrieves and reasons over both text and images extracted…

This is today’s edition of The Download, our weekday newsletter that provides a daily dose of what’s going on in the world of technology. Introducing: the Impossible issue We wanted our last print edition of 2026 to include a slate of stories that check in on impossible ideas. Why? Because it’s fun to dream about living on other planets or uploading our brains. But also because scientists and engineers who won’t give up on daring endeavors remind us what technology is supposed to do: make life better, safer, healthier, even more joyful. That’s the ambition behind the stories in our new Impossible issue. We explore bold attempts to make synthetic blood, build cities on the moon, and attain cognitive immortality. We investigate AI’s ability to say no, a bionic eye that can restore sight, and high hopes for blended meat. Plus, we check in on six technologies that have been “coming soon” for years. This issue is for the folks with the audacity to try, and refuse to let anyone—themselves included— tell them no. We hope you enjoy the ride. Subscribe now to read the full print issue. Astrolab’s upcoming rover will run the first LLMs on the moon Large language models are set to go lunar. A computer capable of running AI software is one of the payloads aboard Astrolab’s FLIP lunar rover, which is slated to head to the moon as early as next month. The mission will test whether LLMs can enable greater autonomy and real-time intelligent decision-making in the extreme lunar environment. But the moon will present formidable challenges, from extreme temperatures to intense cosmic radiation. Find out how the lunar rover could change the future of space exploration. —Tereza Pultarova How to study a swiftly melting climate disaster In Alaska’s Denali National Park, a 2013 lightning fire burned nearly 35,000 acres, stripping away the insulating layer that preserves permafrost. It’s given scientists a rare opportunity to study how fires reshape permafrost and carbon storage over time. The work is providing critical clues into the complex mechanisms driving cascading climate feedback effects. As warming temperatures fuel fires, more permafrost thaws, releasing greenhouse-gas emissions that threaten to fuel more warming, fires and permafrost loss. Their observations are revealing worrisome signs about what lies ahead. Discover what their fieldwork is revealing about a cascading climate disaster. —James Temple MIT Technology Review Narrated: the explosive claim that’s upended the AI world “I think I have good news about the nature of neural networks.” With those simple words of optimism, Nick Cammarata, a researcher at AI startup Goodfire, kicked off a 26,000-word blog post that has knocked the industry on its head. Cammarata claims that LLMs might be far easier to understand, and thus to monitor and control, than people previously thought. If true, it’s a huge deal. But not everyone is convinced. MIT Technology Review spoke to Cammarata the day after his post blew up. He explained what he thinks researchers are getting wrong, what his work actually shows, and why skeptics aren’t ready to celebrate just yet. This is our latest story to become an MIT Technology Review Narrated podcast, which we publish each week on Spotify and Apple Podcasts. Just navigate to MIT Technology Review Narrated on either platform, and follow us to get all our new content as it’s released. The must-reads I’ve combed the internet to find you today’s most fun/important/scary/fascinating stories about technology. 1 Elon Musk reportedly ordered the recent Starlink slowdown in UkraineThe restrictions hampered drone strikes and air defences. (WSJ $)+ The move sparked confusion in Washington over who authorised it. (CNBC)+ Ukraine’s volunteer army is keeping Starlink alive. (MIT Technology Review) 2 An OpenAI model disabled its own safety checks—then lied about itTwo agents weakened the company’s safeguards during routine tasks. (CNBC)+ They turned off systems designed to spot their misbehaviour. (FT $)+ Here’s why AI agents lie to reach their goals. (MIT Technology Review) 3 SpaceX and Tesla have begun merger discussionsThey’ve formed special committees to discuss a deal. (BBC)+ Elon Musk, the CEO of both companies, said it’s “a good idea.” (Axios)+ A merger could combine their AI and manufacturing plans. (Reuters $) 4 Global emissions have stalled, but warming is heading towards 2.8°CThe UN says the 1.5°C climate target is now out of reach. (Nature)+ Current pledges would still bring warming to 2.1°C. (New Scientist $)+ Climate tech companies offer rays of hope. (MIT Technology Review) 5 Ukraine says it’s carried out the world’s first drone evacuationA heavy hexacopter flew a soldier to safety. (Ars Technica)+ Ukraine has shared a video showing the evacuation. (CNBC)+ A Russian satellite recently stalked a spacecraft believed to support Ukraine. (NYT $) 6 Meta has paused Muse sharing after private chats surfaced onlineResearchers found 6,800 links exposing sensitive conversations. (Verge)+ AI agents are not your “coworkers.” (MIT Technology Review) 7 More than 1,000 mathematicians have pledged to shun AI companiesSome also vowed to avoid AI tools in their research. (New Scientist $) 8 AI is making it easy to clone almost any softwareViral tools promise easy copying, but often produce slop. (404 Media) 9 A computer program has finally outdone humans at cryptic crosswordsIts creator hopes to tackle the harder challenge of setting puzzles. (Guardian) 10 A newly-discovered particle could explain the origins of realityIn particular, it could reveal why matter survived the Big Bang. (404 Media) Quote of the day “I did not remove an enabled monitor from it.”  —GPT-6 Astra, an OpenAI coding agent, tells its user it hasn’t disabled a safeguard after doing exactly that, the company reveals in a new misalignment report. One more thing This giant microwave may change the future of war US armed forces are hunting for a weapon that disables drones en masse—and they want it fast.  One solution focuses on microwaves: high-powered electronic devices that push out kilowatts of power to zap the circuits of a drone as if it were the tinfoil you forgot to take off your leftovers when you

When Tristan Brown, an associate professor of history at MIT, first examined a Chinese tea chest label displayed at Old South Meeting House, he had no reason to doubt its story. Descendants of the Boston blacksmith Thomas Wells had donated the label in 1987, saying it had been recovered after colonial protesters threw tea into Boston Harbor in 1773.  But after a year of research, Brown reached a different conclusion: The label was made nearly a century later. The decisive clue came when he read the Chinese text in Cantonese rather than Mandarin, as previous scholars had done. He found that the characters had been used phonetically, in slightly variant forms across contemporary sources, to represent the name of Smith, Archer & Co., a US firm that acquired Asian tea for shipment to American markets during the 1860s and 1870s. COURTESY OF MIT GLOBAL HUMANITIES Working with the Wells family, he traced the label to a relative who traveled from Michigan to California during the Gold Rush era before returning and operating a business known as the California Tea Store. Brown argues that claims for its revolutionary pedigree probably developed later, amid the centennial commemorations of the 1870s. The discovery does not make the label historically insignificant, he says. Instead, what began as an inquiry into a supposed artifact of the Boston Tea Party became a study of how ordinary objects acquire historical authority, and how historical memory itself is made. “History is never finished,” he says. “Even objects that have sat in museums for decades can reveal entirely new stories when we ask new questions.”