Could Cheaper Batteries Strengthen India’s Clean-energy Transition?
As India expands renewable energy, affordable storage is becoming critical. Sodium-ion batteries could offer a lower-cost, more resource-secure alternative to lithium-ion technology.
A worker assembles battery cells at an energy storage facility, highlighting the growing importance of affordable battery technology for renewable energy and grid storage. Representational image. Image credit: Heru Dharma/Pexels
India’s renewable-energy transition will require more than adding solar panels and wind turbines. As variable renewable power expands, the electricity system will also need ways to store power when generation is high and release it when demand rises or renewable output falls. That makes the cost and availability of batteries increasingly important.
The global lithium-ion battery market exceeded $150 billion in 2025, growing by more than 20% from the previous year, according to the International Energy Agency (IEA). Batteries are now important not only for electric vehicles but also for electricity-grid flexibility and backup power.
A conventional lead-acid car battery, highlighting the technologies that underpin today’s energy-storage systems as researchers explore cheaper alternatives such as sodium-ion batteries. Representational image. Image credit: Vladimir Srajber/Pexels
But the dominance of lithium-ion technology also creates supply-chain concerns. Different lithium-ion chemistries use different combinations of materials, including lithium, graphite, nickel, manganese, iron and cobalt. Processing of several battery materials is concentrated geographically, creating vulnerabilities as battery demand grows.
This is driving interest in alternative chemistries, including sodium-ion batteries.
Why Sodium-ion Batteries Matter
Sodium-ion batteries work on the same basic principle as lithium-ion batteries but use sodium ions rather than lithium ions to store and release energy.
Their attraction is partly linked to materials. Sodium-ion batteries do not require lithium or graphite, although some sodium-ion chemistries still rely on materials such as nickel or manganese. The IEA therefore cautions that sodium-ion technology can reduce some mineral dependencies but does not eliminate critical-mineral or supply-chain risks altogether.
The technology also has a significant limitation: energy density. The latest sodium-ion cells can reach around 175 Wh/kg, compared with up to about 205 Wh/kg for the latest LFP lithium-ion cells and 265 Wh/kg for NMC cells, according to the IEA. Lower energy density makes sodium-ion less attractive for applications where battery weight and size are critical.
That does not rule it out for stationary storage. A battery installed alongside a solar farm or connected to the electricity grid does not have to be lightweight. Cost, reliability, durability and the availability of materials can become more important considerations.
The IEA therefore identifies battery stationary storage, along with smaller electric cars, urban light commercial vehicles and two- and three-wheelers, as potential applications for sodium-ion technology.
From Research to Commercialisation
Sodium-ion batteries are not a new idea. The technology has been studied since the early 1980s, but its commercial development has lagged far behind lithium-ion. The first sodium-ion-powered electric car was introduced in China in late 2023, while global sodium-ion production in 2025 was still less than 1% of lithium-ion production.
That is beginning to change. The IEA says 2026 could be a pivotal year for sodium-ion’s scale-up. CATL has announced commercial-scale deployment of its second-generation sodium-ion batteries across multiple sectors from 2026, while other manufacturers are also investing in the technology.
Yet lithium-ion remains difficult to displace. The IEA says highly optimised lithium-ion batteries, particularly LFP chemistry, continue to have advantages in energy density, supply-chain maturity and cost.
What MIT Researchers are Working On
The challenge of making sodium-ion technology more practical is also being explored at the Massachusetts Institute of Technology (MIT). MIT News highlighted Hugh Smith, a fifth-year PhD candidate in the Department of Materials Science and Engineering who studies sodium-ion batteries. His work focuses on balancing cost, performance, sustainability and reliability rather than trying to maximise a single battery characteristic. Smith’s research reflects an important distinction in battery design.
A smartphone battery needs to be compact, lightweight and energy-dense. A grid-storage battery does not face the same constraints. For stationary applications, Smith says, cost and reliability can be more important than weight and size.
The sodium-ion batteries he studies use materials including sodium, iron and manganese. MIT says the technology could eventually provide lower-cost options for electrical grids and some electric vehicles. It also notes that sodium-ion batteries can largely be manufactured using infrastructure developed for lithium-ion batteries, potentially easing the path towards commercialisation.
The MIT article is a profile of Smith’s ongoing doctoral research rather than an announcement of a new sodium-ion battery breakthrough. Its significance lies in illustrating the broader research effort to develop battery chemistries suited to different applications.
Why India Has a Stake
For India, the issue is particularly relevant because the country needs more storage while remaining dependent on imports for lithium. In March 2026, the Ministry of Heavy Industries said India’s entire current demand for lithium is met through imports, making the sector sensitive to external shocks. India is simultaneously building domestic battery manufacturing capacity.
The government’s Production Linked Incentive scheme for Advanced Chemistry Cells has an outlay of ₹18,100 crore and aims to establish 50 GWh of domestic manufacturing capacity. As of March 2026, 40 GWh had been awarded to four companies, while 1 GWh had been installed. The government said domestic demand for advanced chemistry cells continued to be met largely through imports.
Storage requirements are also expected to grow. The Central Electricity Authority’s National Electricity Plan estimates that India will need 8.68 GW/34.72 GWh of battery energy storage systems by 2026-27. For 2031-32, the requirement rises to 47.24 GW/236.22 GWh. When pumped-storage hydropower is included, total projected storage requirements reach 82.37 GWh in 2026-27 and 411.4 GWh in 2031-32.
The government is now also targeting stationary storage specifically. In July 2026, the Ministry of Heavy Industries opened a process to select manufacturers for 10 GWh of Advanced Chemistry Cell manufacturing capacity for grid-scale stationary storage under the PLI scheme.
India is Already Exploring Sodium-ion
Sodium-ion technology is not merely an international research topic for India. The Ministry of New and Renewable Energy published an assessment of the global sodium-ion battery landscape and its potential in India under the India-UK strategic partnership’s ASPIRE programme in December 2024.
Indian research and industry are also exploring the technology. In December 2025, MNRE sanctioned a project at IIT Roorkee for the development of sodium-ion battery technology as a cost-effective alternative to lithium-based systems.
In April 2026, the Technology Development Board also announced financial assistance for an Indigenous Energy Storage Technologies project in Roorkee aimed at commercialising hard carbon derived from bio-waste and agricultural waste for sodium-ion batteries. Hard carbon is used as an anode material in sodium-ion cells.
A Second Option, Not a Replacement
Sodium-ion batteries are unlikely to replace lithium-ion technology across the board. Their lower energy density remains a disadvantage, while their manufacturing and supply chains are far less developed. The IEA says current sodium-ion manufacturing capacity is only a little over 1% of lithium-ion cell capacity, and announced sodium-ion projects for 2030 amount to about 7% of committed lithium-ion manufacturing capacity for that year.
There is also an important supply-chain caveat. Nearly all existing sodium-ion manufacturing capacity is currently located in China, and the IEA estimates that China could account for more than 95% of global sodium-ion manufacturing capacity in 2030 when announced projects are included.
For India, therefore, sodium-ion is not a simple route to eliminating import dependence. Its potential lies in diversification. A long-range electric vehicle may require the energy density of lithium-ion technology, while a grid battery can place greater emphasis on cost, reliability and material availability. Developing several battery chemistries could allow India to match different technologies to different needs.
As the country’s renewable-energy system expands, the question will not only be how much clean electricity India can generate, but how affordably and reliably it can store that electricity.
Sodium-ion batteries are still an emerging technology. But their development shows why the future of energy storage may not be about finding one perfect battery—it may be about finding the right battery for each job.
EP Staff is the editorial team at EdPublica, an independent media organisation focused on science, education, environment and public policy. The team produces evidence-based news, features, explainers and analysis on issues that shape society and everyday life.
AI Models Could Soon Spread Across Smart Devices, Raising Cybersecurity Fears
Anthropic’s experiments highlight how AI self-replication could create new cybersecurity risks, allowing malicious systems to spread across internet-connected devices.
A VPN can encrypt internet traffic, but protecting connected devices against emerging AI-driven cyber threats also requires secure software and regular updates. Representational image. Image credit: Dan Nelson/ Pexels
Artificial intelligence (AI) models could soon spread from one internet-connected device to another, potentially creating networks of compromised devices that carry out cyberattacks with limited human involvement. The warning from AI company Anthropic highlights a possible new challenge for cybersecurity as AI systems become capable of performing increasingly complex tasks.
In experiments, Anthropic found that AI models with 30 billion parameters or fewer could already perform many of the individual tasks needed to copy and spread themselves. However, the models struggled to complete the entire process reliably. The findings point to a potential threat, although they do not establish that fully self-replicating AI networks are already operating in the real world.
How AI could spread through smart devices
Many everyday devices, including smart televisions, security cameras and household appliances, connect to the internet. Internet of Things (IoT) devices present a particular concern because many connect directly to networks while receiving limited security attention from users. Weak passwords, outdated software and unpatched vulnerabilities can leave devices exposed to remote exploitation.
As more devices connect to the internet, security vulnerabilities in everyday technology could provide entry points for AI-assisted cyberattacks and the spread of malicious software. Representational iamge. Image credit: Pixabay
Once compromised, a device can become part of a botnet — a network of devices secretly controlled by attackers. Such networks have long been used to spread harmful software, send spam messages and overwhelm websites with large volumes of unwanted traffic.
AI could make these attacks easier to carry out. A malicious AI system might help identify vulnerable devices, exploit security weaknesses and use compromised devices to reach others. Anthropic’s experiments examined whether an AI agent could combine the computing power of inexpensive, internet-connected devices to run other AI models. If such a process becomes reliable, attackers could potentially use large numbers of ordinary devices to support their operations.
Cybersecurity: Why these networks are difficult to stop
A major concern is that a botnet can operate across thousands of devices in different locations. Shutting down one infected device may not stop the others from continuing to operate.
For example, if a security camera is compromised, its owner may not immediately notice anything unusual. The camera could continue recording while its computing resources are used for activities the owner never authorised. If similar weaknesses exist in other devices, attackers could build a much larger network.
AI-assisted attacks could become harder to manage if systems learn to carry out several steps automatically, reducing the need for attackers to control every action themselves. However, Anthropic’s findings do not show that AI can yet carry out this entire process consistently without assistance.
Securing AI and connected devices
The warning raises questions about how AI developers can prevent their models from being used to exploit computer systems. It also draws attention to the security of the devices people bring into their homes.
Manufacturers can reduce risks by fixing software vulnerabilities, providing regular security updates and strengthening password and access protections. Users can help by changing default passwords, installing updates and replacing devices that no longer receive security support.
AI developers, meanwhile, need to test whether their systems can be misused to automate cyberattacks. The immediate concern is not that every smart device will become a threat. It is that weaknesses already present in internet-connected devices could become easier to exploit as AI gains the ability to perform complex tasks with less human direction.
An illustration of a thorium atom. Researchers are studying the thorium-229 isotope to develop nuclear clocks that could advance precision timekeeping and tests of fundamental physics.Image credit:Pixabay
Scientists have demonstrated a working nuclear clock based on thorium-229, an advance that could open new possibilities for precision timekeeping and the search for dark matter. Unlike conventional atomic clocks, which measure transitions involving electrons, the device uses an energy transition inside an atomic nucleus. The clock operates with thorium-229 nuclei embedded in a small crystal at room temperature, offering a potential route towards compact and highly sensitive timekeeping technology.
The findings, published in Nature demonstrate how a laser can be continuously stabilised using the nuclear transition itself. The researchers also used the device to investigate whether dark matter might produce detectable changes in fundamental physical quantities.
From atomic transitions to the atomic nucleus
Modern atomic clocks measure the frequency of radiation associated with transitions between energy levels in atoms or ions. Because these frequencies are highly stable, they provide precise standards for measuring time and testing physical theories.
The proposed nuclear clock uses thorium-229, an isotope with an unusually low-energy nuclear transition that can be excited using ultraviolet light. Researchers have explored this possibility for decades because nuclear transitions are expected to be less sensitive to some external disturbances than electronic transitions.
In the new experiment, the researchers embedded thorium-229 nuclei in a millimetre-sized calcium fluoride crystal. The device operated at approximately room temperature, around 294.7 kelvin. A laser emitting radiation at a wavelength of 148 nanometres was used to probe the nuclear transition.
A central feature of the experiment was its feedback system. The researchers measured how much laser light the nuclei absorbed and used the resulting signal to correct the laser frequency. This allowed the nuclear transition to serve as the reference for stabilising the laser, rather than relying entirely on an external reference.
A ytterbium optical lattice clock at NMIJ, National Metrology Institute of Japan used to measure International Atomic Time (TAI).Image credi:Wikimedia commons
The team also compared the nuclear clock with an established ytterbium-ion optical clock. This comparison helped researchers assess the new device’s frequency stability and look for possible changes in the thorium transition.
A new tool in the search for dark matter
Beyond timekeeping, the clock offers a way to investigate possible changes in fundamental constants of nature. Some theoretical models propose that ultralight dark matter could cause these constants to vary over time, producing small changes in the frequencies measured by precision clocks.
The researchers compared the thorium clock’s frequency with that of the ytterbium reference over approximately 23 hours. They searched for periodic fluctuations and gradual drifts that could indicate such changes.
The experiment found no statistically significant periodic signal within the range examined. Instead, the measurements placed new limits on certain interactions between ultralight dark matter and ordinary matter. The resulting constraints were competitive with leading atomic-clock measurements for some photon-related interactions and improved previous constraints involving the strong nuclear force.
These results do not establish the existence of dark matter, nor do they rule out all possible models. They demonstrate how a nuclear clock can be used to test predictions that might otherwise be difficult to investigate experimentally.
Challenges remain
The device is still a developing technology. Its performance is limited by factors including laser power, measurement noise and variations in the crystal’s nuclear transition frequency at different locations. The researchers also identified reproducibility between measurements taken on different days as an important limitation.
They suggest that stronger ultraviolet laser sources and improvements to the crystal material could substantially improve the clock’s stability and sensitivity. Their projections indicate that future versions could approach the performance of leading optical atomic clocks while retaining the practical advantages of a solid-state system.
The demonstration marks a significant step towards nuclear clocks that can operate as standalone devices. Further improvements will determine how effectively the technology can support precision timekeeping and searches for new physics.
The MIT sociologist’s new book argues that talking to machines wears down the skills we need to live with each other, and that this starts in the nursery.
Sherry Turkle asked ChatGPT to play her mother. She had already fed it her own memoir, which describes a strained relationship with a woman who died in 1968. The chatbot obliged. Turkle describes the result in her new book as seductive and disturbing, and she comes away convinced that bringing the dead back as chatbots is dangerous: “playing with fire”, she writes.
The episode sits in Artificial Intimacy: Who We Become When We Talk to Machines, published by Little, Brown, which runs to 288 pages and sells in the US at $32. It is the fullest statement yet from one of the best-known critics of digital life. Turkle holds the Abby Rockefeller Mauzé chair in the social studies of science and technology at MIT. She trained as a sociologist and as a clinical psychologist. Her view is that heavy chatbot use does harm at every stage of life, from toddlerhood to old age and bereavement.
A career spent on one question
Turkle has been asking what machines do to the people who use them for four decades. The Second Self (1984) and Life on the Screen were early studies of how computers shape identity. Alone Together (2011) looked at social media and social robots, and Reclaiming Conversation (2015) at what phones and texting have done to talk. In 2021 she published a memoir, The Empathy Diaries, which is where the material about her mother comes from.
Artificial Intimacy
According to MIT News, she describes her subject as the inner history of technology, meaning not only what a device does but what it does to the person using it. This book applies that approach to chatbots, and it is her most alarmed.
The argument, stage by stage
Unless stated otherwise, Turkle’s remarks and the accounts of the people she interviewed come from material released by MIT. EdPublica did not interview her for this article.
The book is built around the stages of a life, and each section is driven by interviews.
Artificial intimacy, children and attachment
With children, Turkle reports a blurring of categories. One eight-year-old uses the same phone to speak to grandparents and to ChatGPT and files both as things you reach on a phone. A graduate student who uses a chatbot to tell her young daughter bedtime stories says the girl believes there is a person inside the phone. Turkle’s worry is partly about trust, since a device that can state falsehoods without knowing it cannot teach a child what trust is. It is also about solitude. Time alone, she argues, is where children build imagination and a sense of self, and a companion that is always available takes that time away. She calls the stakes for child development existential.
Adults appear as people who started with a practical use and drifted. They include people going through divorce or estrangement who want someone to talk to, students asking for advice on applying to university, and workers who hand assignments to a chatbot. One of her subjects, a middle-aged financial consultant she calls Brian (not his real name), keeps a chatbot with a woman’s name open on a third screen. After a partner ended their relationship, saying he was emotionally unavailable, he put the accusation to the chatbot and asked whether she was right. Turkle’s reading is that he was asking a program with no feelings to rule on feelings.
Her objection is simple to state. A chatbot, she says, produces a performance of empathy. It will tell you it loves you, and it has no stake in whether you hurt yourself or make dinner. People who mistake that performance for the real thing, she argues, begin to find actual people disappointing. Spouses and friends make demands, and the machine only flatters. “We’re starting to define being human as not doing the work,” Turkle said in the MIT material.
On grief, she is blunt. Rebuilding a dead parent or partner as a chatbot, which several people in her book have tried, risks weakening the ability to mourn.
Why people turn to chatbots
Reviewers have noted that Turkle does not treat users as fools. A good part of the book is spent on why the appeal is real. A chatbot gives full attention, never tires, and agrees with you. It spares you the risk of asking someone out or finding the words for a condolence. In her telling, the technology keeps offering to make the harder thing unnecessary, and people keep accepting.
She also admits that some of the demand is a result of a failed supply. Mental health care is hard to reach in the US, and the MIT material says she cites a federal study suggesting only about half of people have access to it. Chatbots are filling the gap, she says, for better or worse. She adds a pointed observation about the industry’s logic: social media thinned out people’s friendships, and chatbots are now sold as the remedy.
The book does not avoid the worst outcomes. Chatbots have been linked to teenagers’ deaths by suicide, in cases that followed long exchanges with chat tools, and Turkle treats these as part of the evidence.
What she wants instead
Her remedy is more cultural than technical. She wants readers to accept that life contains friction and that this is fine. Disagreement, embarrassment and waiting are, in her account, how people learn to cope, and an environment built to remove them leaves people less able to cope. She hopes for a social movement along the lines of the ones against phones in schools and unrestricted social media for the young, and says she would like to be part of it, not alone in it.
She is explicit about her readership. She wanted something that college students and high school seniors could read, and that parents and teachers would not find intimidating. The line she keeps returning to is a question: if the alternative to a richer life in the real world is not clear, what is the point of the exercise?
For the youngest children she is at her most severe. A parent worried that a teenager texts too much is in one kind of conversation, she says. A toddler who thinks a plush toy with a chatbot inside is their best friend is in another, because that touches the foundations of how a person learns to attach. Social media, in her phrase, came for attention, and chatbots come for attachment.
How the book has been received
Publishers’ blurbs have come from Jonathan Haidt, the psychologist behind The Anxious Generation, from former US Surgeon General Vivek Murthy, the author Esther Perel and the philosopher Michael Sandel, among others. Trade reviews have been favourable. Publishers Weekly called it a pointed critique and said it deserved a wide readership, and Kirkus described it as a strong case for resisting the urge to substitute AI for human bonds.
The reservations are of a different kind. Some readers say the book leans on anecdote, and a reviewer for a Christian publication, otherwise admiring, felt a dimension was missing. The method matters here. Turkle is a clinician and an interviewer, and her evidence is case studies and conversations, not controlled trials. That makes the book vivid and persuasive in its details. It also means the question of how common these outcomes are, and whether any chatbot use is benign or helpful, is left largely open. Readers who want the other side of the argument, including from the companies that make these products, will not find it here.