The electric vehicle (EV) revolution is well underway, promising cleaner air in our cities and a vital step away from fossil fuels. Yet, this green transition leans heavily on one critical technology: the lithium-ion battery. While revolutionary, these batteries have a well-known Achilles' heel: their ingredients.
Lithium, cobalt, and nickel are expensive, geographically concentrated, and come with significant environmental and ethical baggage. This supply chain bottleneck is what keeps EV prices stubbornly high.
But what if the answer wasn't in a rare earth mineral, but in something far more common? What if the future of affordable electric transport could be powered by salt?
The Problem with Lithium
For decades, lithium-ion (Li-ion) has been the undisputed champion. It's lightweight and packs a lot of power, making it perfect for everything from your phone to a long-range EV. However, as demand soars, its drawbacks become starker:
- Cost: Lithium prices are volatile and high. As the BBC and other outlets have reported, the cost of raw materials is a primary driver of high EV prices.
- Supply: The extraction of these materials is concentrated in just a few countries, creating geopolitical tensions and supply chain risks.
- Ethics & Environment: Mining cobalt, in particular, is linked to severe human rights issues, while the large-scale extraction of lithium is incredibly water-intensive, as noted in reports from various environmental journals.
This has sent scientists and engineers on a quest for an alternative. The leading contender? The sodium-ion (Na-ion) battery.
Enter Sodium-Ion: The Affordable, Abundant Challenger
Sodium-ion batteries work on a very similar principle to their lithium-ion cousins, but they swap out lithium for sodium. And sodium, as you know, is the "Na" in NaCl—table salt. It is one of the most abundant elements on Earth, found everywhere in our oceans and crust.
This simple swap has profound benefits:
- Massively Lower Cost: Sodium is over 1,000 times more abundant than lithium and far easier to source. Crucially, Na-ion batteries can be built without any lithium, cobalt, or nickel. Analysts suggest this could slash battery pack costs by up to 40%, potentially knocking £5,000 to £10,000 off the price of a new EV.
- Sustainability: By eliminating these controversial "critical minerals," Na-ion offers a much cleaner and more ethical supply chain.
- Safety: Na-ion chemistry is generally more stable and less prone to thermal runaway (the technical term for battery fires) than many Li-ion types.
- Impressive Performance: While Li-ion batteries famously struggle in the cold, Na-ion batteries have shown excellent performance in extreme temperatures, maintaining over 80% of their charge in conditions as cold as -40°C.
So, What's the Catch?
If sodium-ion is so good, why aren't all our cars running on it? The primary trade-off has always been energy density.
In simple terms, energy density is the amount of power you can store in a given weight or size. First-generation Na-ion batteries are heavier and bulkier than Li-ion to provide the same amount of energy. For a car, this means a shorter driving range.
Current commercial Na-ion batteries offer around 160 Watt-hours per kilogram (Wh/kg), which is fantastic, but still trails the 180-250+ Wh/kg of today's typical EV batteries.
From Lab to Road: The Gap is Closing
This is where the story gets exciting. That energy density gap, once a deal-breaker, is closing fast.
Global battery giants like China's CATL and BYD are already moving Na-ion batteries into mass production, with the first sodium-powered cars hitting the Chinese market in the last year.
Meanwhile, research breakthroughs are coming thick and fast. A team at the University of Surrey, for example, recently announced a new sodium-based material that could lead to faster charging and an energy density that rivals mid-tier lithium-ion cells.
The UK is a key hub for this innovation. The Faraday Institution, the UK's independent centre for battery research, is running a major project (NEXGENNA) dedicated to developing high-performance Na-ion batteries. What's more, UK-based companies like Faradion—a true pioneer in this field—and Batri are actively developing and commercialising this technology, aiming to position Britain at the forefront of this next-generation battery.
A "Two-Battery" Future?
Sodium-ion is probably not a "lithium killer"—at least, not yet. Instead, we are likely moving towards a "two-battery" future.
- Lithium-ion will likely remain the standard for high-performance, long-range premium vehicles where cost is less of an issue.
- Sodium-ion looks set to dominate the other end of the market: affordable, entry-level city cars.
This is arguably the most important part of the EV transition. To truly make a difference to our climate goals, EVs need to be accessible to everyone, not just the wealthy. Sodium-ion technology is the most promising key we have to unlock the truly affordable, sustainable electric car.
What do you think? Would you be willing to trade some driving range for a significantly cheaper and more sustainable electric car? Let us know your thoughts in the comments below.
Sources
UK Research and Development
- The Faraday Institution: The UK's independent research centre for battery technology. Their "NEXGENNA" project is specifically focused on developing next-generation, high-performance sodium-ion batteries.
Source: The Faraday Institution. (n.d.). NEXGENNA – Sodium-ion Batteries. Available at: https://www.faraday.ac.uk/research/beyond-lithium-ion/sodium-ion-batteries/ - University of Surrey: Details the recent breakthrough in using a hydrated sodium vanadate material to improve energy storage and charging speeds in sodium-ion cells.
Source: Energy Live News. (2025, Oct 21). Battery breakthrough could power greener energy and desalinate seawater. Available at: https://www.energylivenews.com/2025/10/21/battery-breakthrough-could-power-greener-energy-and-desalinate-seawater/ - Faradion: The website of the pioneering UK-based sodium-ion battery technology company.
Source: Faradion. (n.d.). Home. Available at: https://faradion.co.uk/
Commercialisation and Mass Production
- EVWorld: Reports on the strategic race to electrify, noting that Chinese firms like CATL and BYD are leading the mass production of sodium-ion powered vehicles, expected by 2026.
Source: EVWorld. (2025, Oct 23). The Battery Divide: Strategic Choices in the Global Race to Electrify Mobility. Available at: https://www.evworld.com/article.php?id=472 - Reuters / YouTube: Discusses CATL's "Naxtra" sodium-ion battery, its performance specifications, and its potential to disrupt the market with significantly lower costs.
Source: Various news reports, including coverage on YouTube, referencing CATL's product announcements from 2024/2025.
Comparison: Sodium-Ion vs. Lithium-Ion
- Stanford University: Provides a comprehensive comparison, highlighting that while sodium-ion has lower energy density, it needs breakthroughs (which are now happening) to compete on price, especially if lithium prices remain low.
Source: Stanford University. (2025, Jan 13). Sodium-ion batteries need breakthroughs to compete. Available at: https://news.stanford.edu/stories/2025/01/sodium-ion-batteries-need-breakthroughs-to-compete - Greenly: A detailed breakdown comparing the cost, environmental impact, safety, and performance of both battery types, noting sodium's advantages in raw material abundance and safety.
Source: Greenly. (2023, Nov 9). Sodium batteries: A better alternative to lithium?. Available at: https://greenly.earth/en-gb/blog/industries/sodium-batteries-a-better-alternative-to-lithium
Environmental & Ethical Impact of Lithium-Ion
- Earth.Org: Outlines the significant environmental impacts of lithium and cobalt mining, including habitat destruction, water pollution, and high carbon emissions from extraction.
Source: Earth.Org. (2023, Mar 31). The Environmental Impacts of Lithium and Cobalt Mining. - Farmonaut: Details the specific issues tied to cobalt and lithium, including deforestation, water depletion in mining regions, and the well-documented use of child labour and unsafe conditions in artisanal mines in the Democratic Republic of Congo (DRC).
Source: Farmonaut. (2025). Cobalt And Lithium Mining: 2025 Environmental Impact.
