Category: 3. Business

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Anthropic plans to invest $50bn in building artificial intelligence infrastructure in the US over the coming years, as the start-up races to secure new computing power.

The Claude chatbot maker on Wednesday said it would develop new data centres in New York and Texas with UK-based cloud computing start-up Fluidstack. The sites will bolster Anthropic’s research and development as well as providing power for its existing AI tools.

“We’re getting closer to AI that can accelerate scientific discovery and help solve complex problems in ways that weren’t possible before. Realising that potential requires infrastructure that can support continued development at the frontier,” said Dario Amodei, chief executive and co-founder of Anthropic.

The investment follows a flurry of deals by Anthropic’s chief rival OpenAI to secure chips and computing capacity from Nvidia, AMD, Broadcom, Oracle and Google, estimated to be worth about $1.5tn.

The circular arrangements between companies that act as suppliers, investors and customers of each other, combined with booming AI valuations, have added to concerns about a bubble in the sector.

Anthropic has also moved to boost its computing power this year. Last month, the four-year-old start-up signed a deal to secure access to 1mn Google Cloud chips to train and run its AI models.

The San Francisco-based group also has a partnership with Amazon, which is the start-up’s “primary” cloud provider and a large investor. It has invested $8bn in Anthropic and is building a 2.2GW data-centre cluster in New Carlisle, Indiana, to help train its AI models.

Its latest agreement will involve it partnering with Fluidstack, a small start-up that this year signed a deal with the French government to build a major computing cluster in France. Anthropic said it chose the company for its “exceptional agility”.

“We’re proud to partner with frontier AI leaders like Anthropic to accelerate and deploy the infrastructure necessary to realise their vision,” said Gary Wu, co-founder and CEO of Fluidstack.

Anthropic, which was recently valued at $183bn post-money, was founded by a group of former OpenAI employees. While OpenAI has focused largely on its consumer product ChatGPT, Anthropic has targeted enterprise customers.

The group’s run-rate revenue — a projection of annual revenue based on recent performance which is favoured by start-ups — shot from $1bn at the start of the year to $7bn last month. In September the company raised $13bn from investors including Iconiq Capital and Lightspeed Venture Partners.

Introduction

On behalf of the New York Fed, let me welcome you all to this year’s U.S. Treasury Market Conference. Many thanks to the distinguished speakers and panelists for joining us here, and to the event organizers for putting together today’s outstanding agenda. I’m looking forward to a valuable and productive conversation.

This gathering is a recurring calendar item every fall. But the topics that we discuss each year do not stand alone. Think of it as leveling up in a video game—which is one of my favorite pastimes by the way, or dare I say, “present times”. At each conference, we advance our understanding of the Treasury market to the next level. And in the genre of gaming, this game is multiplayer. It’s remarkable to think about what we’ve accomplished in this decade-long enterprise of interagency collaboration. This work continues to be imperative, so we must keep playing. I mean that in the working sense, of course.

Before I keep going, I must give the standard Fed disclaimer that the views I express today are mine alone and do not necessarily reflect those of the Federal Open Market Committee (FOMC) or others in the Federal Reserve System.

Three Levels of Play

The remarks that I’ve given at past conferences have focused on taking stock of the Treasury market and sharing updates on our collective efforts.¹ My comments today will be a retrospective into the events, developments, and lessons learned over the past seven years. I will then explain how all of that has shaped the FOMC’s thinking around monetary policy implementation and the design of our ample reserves implementation framework. I’ll also bring you up to speed with regard to where the Federal Reserve stands on its balance sheet strategy.

So, let’s return to the video game analogy and start at level one—the episode of volatility known as the “flash rally” of 2014. That period of market stress served as a sharp reminder that financial markets are not static: they evolve in response to changes in technology, regulation, business models, and with the addition of new players and participants.

That initial level made it clear that safeguards and systems must evolve so that these markets can continue to function well in every circumstance and under any condition. So, from there, we jumped to the next level. And that’s the imperative of market resiliency. We learned the importance of creating a system that can better withstand the unforeseeable and the unpredictable. Because when the unforeseeable and unpredictable did happen, as we saw in the “dash-for-cash” in 2020, it resulted in significant stresses in the Treasury market and related markets that threatened to spread to broader financial conditions.

This leads me to level three. A resilient financial system is critically important for monetary policy. Because monetary policy influences the economy by affecting financial market conditions, its effectiveness relies on well-functioning markets, with the Treasury market at the heart of it all.

Good news—we’ve unlocked the next level of my remarks. And that is an explanation of the FOMC’s approach to monetary policy implementation to support effective interest rate control and smooth functioning of these core markets.

Framing the Frameworks

We’ve established that monetary policy implementation frameworks are critically important to the conduct of monetary policy.²

In supplying reserves to the banking system, the Federal Reserve has multiple goals that frequently involve trade-offs.³ First and foremost, it targets a level of the policy interest rate and aims to minimize the variability of the policy rate around that target. In addition, it has objectives related to supporting financial stability and the smooth functioning of financial markets.

The core of any operational framework is the supply of reserves, which can range from a low level, or “scarce,” to “ample” and “abundant.” The “price” of reserves is the spread between the market interest rate and the rate earned for holding reserves at the central bank. When reserves are scarce, the slope of the demand curve for reserves is steep. A small change in the quantity of reserves results in a meaningful change in the spread. When reserves are ample, the demand curve flattens but still slopes downward, so that small changes in the quantity of reserves have modest effects on the spread. And when reserves are abundant, the demand curve is essentially flat.

A central bank has two sets of tools it can use to supply reserves. First, it chooses an ex ante aggregate level of reserves to supply to the banking system. Second, it may make available lending facilities to the banking system that offer loans to financial institutions at an interest rate determined by the central bank. If the ex ante supply of reserves is sufficiently low, the additional demand will be met by the lending facilities. Note that both tools are a means to supply reserves: In the first, the supply is set in advance, while with the latter, it adjusts endogenously to market conditions.

It is worth emphasizing that the two tools can be mutually reinforcing in achieving desired outcomes. For example, lending facilities limit upward movements in interest rates on days of high demand, thereby reducing the ex ante supply of reserves needed to control short-term rates.⁴

Federal Reserve: Ample Reserves and Tools

The Fed’s operational framework has evolved over time, reflecting its experience with large balance sheets since the global financial crisis.⁵ In January 2019, when the decline in the Fed’s asset holdings implied that the quantity of reserves would soon fall below an “abundant” level, the FOMC formally adopted an ample reserves strategy.⁶

The FOMC has defined this framework as one in which “control over the level of the federal funds rate and other short-term interest rates is exercised primarily through the setting of the Federal Reserve’s administered rates, and in which active management of the supply of reserves is not required.”⁷ Accordingly, the ex ante supply of reserves is chosen to be sufficiently large to meet the demand for reserves on most days.

One important tool the FOMC has established to ensure interest rate control is the overnight reverse repo facility (ON RRP), which, alongside the interest paid on reserve balances (IORB), helps set a floor for the federal funds rate. Through the ON RRP, eligible counterparties “lend” to the Federal Reserve at the rate set by the FOMC, currently at the bottom of the target range for the federal funds rate. Usage of the ON RRP adjusts automatically to market conditions, rising and falling with supply and demand, which is particularly important in a dynamic market.

The ON RRP has proven to be a very effective and flexible tool to support interest rate control to the downside. When Federal Reserve asset holdings push reserves above ample, the ON RRP relaxes the tight relationship between balance sheet size and reserves and acts as a safety valve in supporting smooth transmission of monetary policy to markets. As the size of the balance sheet falls, market rates rise above the rate offered at the ON RRP and, as a result, usage of the ON RRP declines to very low levels. The dynamic usage of the ONRRP is seen in Figure 1, which shows average monthly usage of the ON RRP from 2016 through October of this year. The ON RRP was used extensively when it was economically sensible for the Fed’s counterparties to do so. By contrast, it has very limited usage when repo rates are well above the ON RRP rate, as is the case today.

In 2021, the Federal Reserve introduced the Standing Repo Facility (SRF), which nicely complements the ON RRP by providing interest rate control to the upside.⁸ The SRF rate is set at the top of the FOMC’s target range for the federal funds rate. This combination of an ample supply of reserves and an SRF rate at the top of the target range reduces the day-to-day reliance on the facility except during periods of significant upward pressure on rates resulting from strong liquidity demand or market stress.

By ensuring that adequate liquidity will be available in a wide variety of circumstances, the SRF plays a critical role in capping temporary upward pressure on rates and assures markets of effective interest rate control and smooth market functioning. It is best thought of as a way of making sure that the overall market has adequate liquidity consistent with the FOMC’s desired level of interest rates. In that regard, it differs from other lending facilities—such as the discount window—that aim to provide individual banks with liquidity when the need arises.

The SRF has been effective as reserves have moved from abundant toward ample. Over the past two months, SRF usage has risen from essentially zero to having greater frequency and higher volume of take-up, especially on days of temporary repo market pressures, as shown in Figure 2. Like the ON RRP facility, the SRF’s effectiveness relies on market participants availing themselves of the SRF based on market conditions, free of worries about stigma or other impediments. I fully expect that the SRF will continue to be actively used in this way and contain upward pressures on money market rates.

Federal Reserve: The Way Forward

At the onset of the pandemic, the Fed, along with central banks around the world, responded quickly to restore market functioning,⁹ causing reserves to rise well above ample, as they did in many jurisdictions.

In June of 2022, the Fed began the process of reducing the size of its balance sheet to transition toward an ample level of reserves.¹⁰ The FOMC said it intended to stop balance sheet runoff when it deemed reserves were somewhat above ample, and then allow reserves to decline further as other liabilities, such as currency, grow.

The process has worked according to plan. The Fed’s securities holdings have shrunk from a peak of about $8-1/2 trillion in 2022 to $6-1/4 trillion today. At its meeting in October, the FOMC decided it would conclude the reduction of its aggregate securities holdings on December 1.¹¹ This decision was based on clear market-based signs that we had met the test of reserves being somewhat above ample.¹² In particular, repo rates have increased relative to administered rates and have exhibited more volatility on certain days. Accordingly, we have been seeing more frequent use of the SRF. And the effective federal funds rate has increased somewhat relative to the IORB after years of that spread being at a stable level. These developments were expected as the supply of reserves closed in on ample.¹³

Looking forward, the next step in our balance sheet strategy will be to assess when the level of reserves has reached ample. It will then be time to begin the process of gradual purchases of assets that will maintain an ample level of reserves as the Fed’s other liabilities grow and underlying demand for reserves increases over time. Such reserve management purchases will represent the natural next stage of the implementation of the FOMC’s ample reserves strategy and in no way represent a change in the underlying stance of monetary policy.

Determining when we are at ample reserves is an inexact science. I am closely monitoring a variety of market indicators related to the fed funds market, repo market, and payments to help assess the state of reserve demand conditions. Based on recent sustained repo market pressures and other growing signs of reserves moving from abundant to ample, I expect that it will not be long before we reach ample reserves.

Conclusion

With that, we’ve arrived at the endgame of my remarks. We’ve learned a lot over the past decade. The FOMC’s monetary policy implementation framework is designed to support an adequate supply of liquidity under a wide range of circumstances. The combination of an ample supply of reserves and the Standing Repo Facility enables the Committee to maintain strong interest rate control and flexibility regarding changes in the size of its balance sheet. This operational framework has proven to be highly effective—and continues to work as designed.

Figures

How many pounds of rice do you think you eat in a year? According to USA Rice, the average American enjoys 27 pounds annually — equivalent to the weight of a case of bottled water. In fact, rice isn’t just a mainstay in pantries, it’s a staple for more than half the world, and a vital source of income for 19%¹ of the world’s population.

With extreme weather events—such as droughts, floods, pests, and diseases—threatening rice yields and demand for rice in the United States continuing to rise, it is crucial for industry leaders like Mars to advance supply chain resiliency strategies to secure the future of rice.

Rising to the Challenge: How Mars is Supporting Rice Farming Resilience
The Arkansas Delta is a region in the eastern part of Arkansas that stretches along the Mississippi River and is one of the most productive agricultural areas in the country. This area accounts for 49.3% of total U.S. rice production and 49.9% of the total acres planted in 2024². Today, its once-fertile fields are grappling with droughts, saltwater from rising sea levels and floods, among other challenges. These challenges all point to an urgent need for innovation to secure and maintain this essential crop’s environment — one grain at a time.

As the manufacturer of iconic brands like Ben’s Original™— one of the world’s most recognized rice brands — as well as Tasty Bite® and Seeds of Change™, Mars, the maker of more than 40 U.S. food, snacking and pet brands, deeply understands the role rice plays in kitchens across the U.S. and around the world. Rice is more than just a staple ingredient; it’s a cornerstone of culture and nourishment for more than four billion people worldwide. That’s why our role goes far beyond simply selling products — it’s about honoring rice’s global significance and supporting the communities, farmers and families who depend on it.

“As a leader in the rice industry, we recognize our opportunity to help farmers across our value chain address environmental challenges that threaten their livelihoods,” said Dave Dusangh, President Mars Food & Nutrition, North America. “By collaborating closely with our partner farmers, we are working to build a more sustainable, resilient and innovative rice supply chain that benefits both people and the planet.”

Innovating for a Water-Smart Future
We’re using our longstanding expertise and global resources to help farmers adopt and scale advanced agricultural techniques that conserve water while reducing greenhouse gas emissions.

Conventional rice cultivation often relies on continuously flooded fields, which is water intensive and restricts oxygen in the soil and creates conditions for methane-producing bacteria — leading to greenhouse gas emissions. Mars is helping farmers adopt innovative water management techniques and technologies that improve water efficiency, strengthen climate resilience, and cut emissions. A few of these examples include:

• Alternate wetting and drying (AWD): A water management technique that allows rice fields to alternate between periods of flooding and drying, rather than maintaining continuous flooding throughout the growing season. This approach has been shown to reduce the amount of water used by up to 30% and reduce the amount of GHG emissions produced by over 40%³ each growing season.
• Multiple inlet rice irrigation (MIRI): This system optimizes how water is delivered using multiple inlets in pipes placed across a field. This distributes water more efficiently, cutting down on water usage, and reducing emissions.
• Row rice, or furrow irrigation: A method that bypasses the need to flood fields, while improving ease of crop rotation. Using this technique, water is applied in rows rather than flooding across the entire section of the field.
• Zero-grade fields are precision-leveled to ensure a flat surface with no slope, allowing water to flow evenly across the field and eliminating the need for internal levees or side inlets. This minimizes the need for intensive tilling, further improving efficiency and enabling farmers to save up to 37%⁴ more water each growing season compared to traditional contoured or leveed fields.

While these are promising solutions, shifting away from traditional methods can be challenging. The cost of new systems, concern about potential yield loss and difficulty of changing longstanding habits all make adoption a challenge for many farmers. Mars is supporting farmers by paying premiums on top of the commodity price to incentivize the adoption of new practices, as well as sharing data so Mars can measure the environmental benefits of these practices. This data sharing has helped show farmers in the Mars rice supply chain that embracing these practices hasn’t negatively impacted their crop yields. In fact, research has shown that using zero-grade fields with the AWD irrigation method reduces water usage by 65%⁵ while still providing the same crop yields.

“The role Mars plays in helping us adopt climate-smart agriculture practices is critical because it gives us an incentive to go out there and try something new,” says Terry Gray, an Arkansas rice farmer in the Mars Food & Nutrition rice supply chain. “We’re trying out these practices to grow the same yields with less strain on the land — and the results are showing it’s better for the environment all around.”

Partnering to Protect Farmers and the Planet
“The challenges faced by rice farmers today demand bold leadership, and partners like Mars are vital in driving meaningful change,” said Peter Bachmann, President and CEO, USA Rice. “By leveraging its resources, expertise and scale, Mars is helping farmers adopt climate-smart agriculture practices that not only sustain their livelihoods but also safeguard the environment.”

At Mars, mutuality is one of our core guiding principles. Collaboration with partners throughout our supply chain is essential to how we’re working to shape a more secure future for farmers, communities and the planet. Our approach to rice farming reflects this value, as we address challenges and build the future we envision together, every step of the way.

Through a steadfast commitment to our Sustainable in a Generation plan, Mars is championing impactful innovation that strengthens U.S. rice farming, setting an example across global food systems in an ever-evolving world.
 

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1. Rice – Rice Sector at a Glance | Economic Research Service. n.d. https://www.ers.usda.gov/topics/crops/rice/rice-sector-at-a-glance

2. Handbook, IPM, AND-STaR | Arkansas Cooperative Extension Service https://www.uaex.uada.edu/farm-ranch/crops-commercial-horticulture/rice/

3. Mars & Riceland Sustainable Rice Program (Arva Intelligence)

4. Massey et al. 2022, Direct Comparisons of four rice irrigation systems on a commercial rice farm, Agricultural Water Management, Vol 266, 31 May 2022 https://www.sciencedirect.com/science/article/abs/pii/S0378377422001536

5. Mars & Riceland Sustainable Rice Program (Arva Intelligence)

New strategic alliance brings CrowdStrike Falcon Sensor and OverWatch Threat Hunting to F5 BIG-IP, free of charge through October 14, 2026

November 12, 2025 – SEATTLE and AUSTIN, Texas – F5 (NASDAQ: FFIV) and CrowdStrike (NASDAQ: CRWD) today announced a new strategic technology alliance and first-of-its-kind integration that brings advanced workload security to F5 BIG-IP. By enabling F5 customers to embed CrowdStrike’s Falcon Sensor directly into F5 BIG-IP and leverage CrowdStrike Falcon® Adversary OverWatch managed threat hunting service, the companies are advancing adaptive, AI-driven security to the network perimeter where enterprises front their most critical application and API traffic.

Extending detection and response beyond the endpoint

For years, the cybersecurity paradigm has centered on the edge as the primary battleground. Organizations rightly focused on securing laptops, desktops, and mobile devices with endpoint detection and response (EDR) software. This is crucial because these are the gateways through which users interact with corporate data and where many initial intrusions occur. However, attackers don’t stop at a compromised laptop; they see the entire network infrastructure as a sprawling set of cross-domain targets. To stop modern attacks, organizations need protection that extends beyond the endpoint – unifying visibility and defense across every domain that adversaries target.

“Today’s threat landscape demands taking the power of the Falcon platform beyond the endpoint,” said George Kurtz, CEO and founder of CrowdStrike. “We’re taking a bold step to move cybersecurity forward: normalizing the deployment of detection and response sensors across every attack surface, including network appliances. We’re pleased to take the first step by embedding CrowdStrike Falcon and OverWatch onto F5 BIG-IP. The Falcon platform has become essential for securing the modern enterprise.”

“For too long, network devices have lacked the same protection as other endpoints, even as they sit in front of the world’s most critical applications and APIs,” said François Locoh-Donou, President and CEO of F5. “The security incident we recently disclosed underscores how important it is to close this gap and continue raising the security bar across the industry. Delivered on the F5 Application Delivery and Security Platform (ADSP), CrowdStrike Falcon and OverWatch for BIG-IP brings AI-driven detection and threat hunting to the network edge. With over 200 customers already using Falcon for BIG-IP in their networks, our collaboration with CrowdStrike is enabling security teams to reduce blind spots and accelerate response times in their environments.”

CrowdStrike Falcon and OverWatch for F5 BIG-IP available now, free through October 14, 2026, to F5 customers

CrowdStrike Falcon Sensor and Overwatch Threat Hunting are available for BIG-IP Virtual Edition (VE) with availability on BIG-IP hardware systems by the end of the calendar year. F5 is providing eligible BIG-IP customers with complimentary access through October 14, 2026, to enable the immediate adoption of AI-native security and threat hunting at the network level without upfront costs. Interested F5 BIG-IP customers can view the Knowledge Base article or contact F5 for further information and assistance with onboarding.

Additional Resources:

To learn more, read the blog, watch the demo video, or visit the F5 and CrowdStrike partnership page.

About F5

F5, Inc. (NASDAQ: FFIV) is the global leader that delivers and secures every app. Backed by three decades of expertise, F5 has built the industry’s premier platform—F5 Application Delivery and Security Platform (ADSP)—to deliver and secure every app, every API, anywhere: on-premises, in the cloud, at the edge, and across hybrid, multicloud environments. F5 is committed to innovating and partnering with the world’s largest and most advanced organizations to deliver fast, available, and secure digital experiences. Together, we help each other thrive and bring a better digital world to life.

For more information visit f5.com

Explore F5 Labs threat research at f5.com/labs

Follow to learn more about F5, our partners, and technologies: Blog | LinkedIn | X | YouTube | Instagram | Facebook

F5 and BIG-IP are trademarks, service marks, or tradenames of F5, Inc., in the U.S. and other countries. All other product and company names herein may be trademarks of their respective owners. The use of the terms “partner,” “partners,” “partnership,” or “partnering” in this press release does not imply that a joint venture exists between F5 and any other company.

About CrowdStrike

CrowdStrike (NASDAQ: CRWD), a global cybersecurity leader, has redefined modern security with the world’s most advanced cloud-native platform for protecting critical areas of enterprise risk – endpoints and cloud workloads, identity and data.

Powered by the CrowdStrike Security Cloud and world-class AI, the CrowdStrike Falcon® platform leverages real-time indicators of attack, threat intelligence, evolving adversary tradecraft and enriched telemetry from across the enterprise to deliver hyper-accurate detections, automated protection and remediation, elite threat hunting and prioritized observability of vulnerabilities.

Purpose-built in the cloud with a single lightweight-agent architecture, the Falcon platform delivers rapid and scalable deployment, superior protection and performance, reduced complexity and immediate time-to-value.

CrowdStrike: We stop breaches.

Learn more: https://www.crowdstrike.com/

Follow us: Blog | X | LinkedIn | Instagram

Start a free trial today: https://www.crowdstrike.com/trial

# # #

This press release may contain forward looking statements relating to future events or future financial performance that involve risks and uncertainties. Such statements can be identified by terminology such as “may,” “will,” “should,” “expects,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “potential,” or “continue,” or the negative of such terms or comparable terms. These statements are only predictions and actual results could differ materially from those anticipated in these statements based upon a number of factors including those identified in the company’s filings with the SEC.

Though she studied psychology in college, King fell in “love, love, love” with television news while working as a production assistant at a local CBS station and then committed to what would become a five-decade career in journalism. After stints producing, reporting for, and hosting local programs, she took to the national stage with her short-lived The Gayle King Show but soon found another home at the media company of her longtime friend Oprah Winfrey. Since 2012, she has anchored CBS Mornings, through changes in cohosts and, most recently, a management shake-up.

Picture an electric car that could go 600, 700 or even 1,000 miles on a single charge. That’s much farther than the longest-range electric vehicles on the U.S. market, according to Car and Driver magazine – and twice as far the official rating for the long-range, rear-wheel-drive Tesla Model 3, which has a maximum rated range of 363 miles.

Current EVs use lithium-ion batteries, which are also found in smartphones, laptops and even large-scale energy storage systems connected to the power grid. A standard for decades, these batteries have been tweaked and improved by generations of scientists and are now close to their physical limits. Even with the best materials and most optimized designs, there is only so much energy that can be packed into a lithium-ion battery.

I’m a materials engineer who studies these batteries and seeks alternatives with better performance, improved environmental sustainability and lower cost. One promising design uses sulfur, which could boost battery capacity significantly, though some key roadblocks remain before it can be widely used.

Lithium-sulfur vs. Lithium-ion

Any battery has three basic components: a positively charged region, called the cathode; a negatively charged region, called the anode; and a substance called the electrolyte in between, through which charged atoms, also known as ions, move between the cathode and anode.

In a lithium-ion battery, the cathode is made of a metal oxide, typically containing metals such as nickel, manganese and cobalt, bonded with oxygen. The materials are layered, with lithium ions physically between the layers. During charging, lithium ions detach from the layered cathode material and travel through the electrolyte to the anode.

The anode is usually graphite, which is also layered, with room for the lithium ions to fit between them. During discharge, the lithium ions leave the graphite layers, travel back through the electrolyte and reinsert into the layered cathode structure, recombining with the metal oxide to release electricity that powers cars and smartphones.

In a lithium-sulfur battery, the lithium ions still move back and forth, but the chemistry is different. Its cathode is made of sulfur embedded in a carbon matrix that conducts electricity, and the anode is made primarily of lithium itself, rather than graphite layers with lithium in between.

During discharging, the lithium ions travel from the anode, through the electrolyte to the cathode, where – rather than sliding in between the cathode layers – they chemically convert sulfur in sequential steps to a series of compounds called lithium sulfides. During charging, the lithium ions separate from the sulfide compounds, leave the cathode behind and travel back to the anode.

The charging and discharging process for lithium-sulfur batteries is a chemical conversion reaction that involves more electrons than the same process in lithium-ion batteries. That means a lithium-sulfur battery can theoretically store much more energy than a lithium-ion battery of the same size.

Sulfur is inexpensive and abundantly available worldwide, meaning battery manufacturers do not need to rely on scarce metals such as nickel and cobalt, which are unevenly distributed on Earth and often sourced from regions such as the Democratic Republic of Congo, which has limited worker safety regulations and fair labor practices.

Those advantages could deliver batteries with far more capacity and that are cheaper and more sustainable to produce.

Why aren’t lithium-sulfur batteries widely used yet?

The biggest obstacle to mass production and use of sulfur-based batteries is durability. A good lithium-ion battery, like those in an electric vehicle, can go through thousands of cycles of discharging and recharging before its capacity starts to fade. That amounts to thousands of car rides.

But lithium-sulfur batteries tend to lose capacity much more quickly, sometimes after fewer than 100 cycles. That’s not very many trips at all.

The reason lies in the chemistry. During the chemical reactions that store and release energy in a lithium-sulfur battery, some of the lithium sulfide compounds dissolve into the liquid electrolyte of the battery.

When that happens, those amounts of both sulfur and lithium are removed from being used in any remaining reactions. This effect, known as “shuttling,” means that with each round of discharging and recharging, there are fewer elements available to release and store energy.

In the past couple of decades, research has produced improved designs. Earlier versions of these batteries lost much of their capacity within a few dozen discharge–recharge cycles, and even the best laboratory prototypes struggled to survive beyond a few hundred.

New prototypes retain more than 80% of their initial capacity even after thousands of cycles. This improvement comes from redesigning the key parts of the battery and adjusting the chemicals involved: Special electrolytes help prevent the lithium sulfides from dissolving and shuttling.

The electrodes have also been improved, using materials such as porous carbon that can physically trap the intermediate lithium sulfides, stopping them from wandering away from the cathode. This helps the discharge and recharge reactions happen without so many losses, making the reactions more efficient so the battery lasts longer.

The road ahead

Lithium-sulfur batteries are no longer fragile laboratory curiosities, but there are significant challenges before they can become serious contenders for real-world energy storage.

In terms of safety, lithium-sulfur batteries have a less volatile cathode than lithium-ion batteries, but research is continuing into other aspects of safety.

Another problem is that the more energy a lithium-sulfur battery stores, the fewer cycles of charging it can handle. That’s because the chemical reactions involved are more intense with increased energy.

This trade-off may not be a major obstacle for using these batteries in drones or grid-level energy storage, where ultrahigh energy densities are less critical. But for electric vehicles, which demand both high energy capacity and long cycle life, scientists and battery researchers still need to sort out a workable balance. That means the foundation for the next generation of lithium-sulfur batteries is likely still a few years down the road.