The laboratory method was elegant enough: convert silica to porous silicon at relatively modest temperatures, skip the toxic silane gas, cut the carbon emissions. Whether it could work at industrial scale—and whether battery makers would actually adopt it—remained open questions when AmpliSi incorporated last August.
Now the Sheffield-based spin-out has £2 million in pre-seed funding to find out.
Clean Growth Fund and Northern Gritstone co-led the round, disclosed March 12, 2026, in what marks the first publicly announced deployment from Clean Growth Fund's recently closed Fund II. The capital gives AmpliSi runway to move beyond lab benches and into the messier, more expensive work of proving that its silicon anode material can scale—and that customers in the mobility sector will pay for it.
The Silicon Promise, and Its Complications
Silicon anodes have long tantalized battery engineers. They can store roughly ten times more lithium than the graphite anodes that dominate today's lithium-ion cells, a characteristic that translates to lighter batteries with longer range. Electric vehicle makers would like that very much.
But silicon anodes come with baggage. Traditional production routes are energy-intensive and high-emission, involving processes that can reach 1,500°C or rely on silane, a pyrophoric gas with its own handling complexities. The result: a material that promises greener cars but arrives via a decidedly ungreen manufacturing pathway.
AmpliSi's pitch hinges on a magnesiothermic reduction process developed at the University of Sheffield. The method operates below 400°C, avoids silane entirely, and yields a porous silicon structure the company says can slot into existing battery production lines without requiring manufacturers to overhaul their supply chains. Prof. Siddharth Patwardhan, who led the underlying academic research, now advises the company as Chief Scientific Advisor. CEO Dr. Ruth Sayers and CTO Dr. Gwen Chimonides complete the core team.
Whether "drop-in replacement" proves to be more than marketing language will depend on field testing and customer validation—steps that lie ahead, not behind.
Capital from Climate-Tech Backers
Clean Growth Fund deployed the investment from Fund II, which held a first close at £49 million in August 2025 and is targeting £150 million total. Northern Gritstone, a deep-tech investor with institutional backing from universities and regional partners, matched the commitment. AmpliSi had participated in Northern Gritstone's NG Studios program, a venture-building effort that provides scaffolding for early-stage companies navigating incorporation and team assembly.
Cambridge Future Tech, another venture builder, also supported AmpliSi's formation, though its exact role and any equity stake remain undisclosed.
The funding announcement offered warm words but few hard commitments. A Clean Growth Fund managing partner noted that silicon anodes "offer dramatic advantages over graphite," but acknowledged adoption has been "limited by challenges including the emissions intensity of current production processes." Sayers framed the round as a chance to "move beyond proof-of-concept and scale a product that integrates seamlessly into existing supply chains."
Seamless integration is a high bar. Battery manufacturers are conservative buyers, understandably so given the liability risks and performance requirements of EV cells. AmpliSi has not disclosed customer names, offtake agreements, or production site plans—standard omissions at the pre-seed stage, but also indicators of how much work remains.
A Crowded Field with Deep Pockets
AmpliSi is hardly alone in chasing silicon anodes. The category has attracted serious capital, particularly in the United States. Group14 Technologies pulled in $463 million last August to scale its silicon-carbon composite material, pushing its cumulative funding past $1 billion. Sila, another U.S. player, opened a factory in September 2025 with initial capacity to supply anodes for 20,000 to 50,000 electric vehicles annually.
Closer to home, UK-based Nexeon has inked a long-term supply agreement with Panasonic and is preparing initial shipments from a production facility in South Korea. Each of these competitors underscores the commercial potential of silicon anodes. Each also highlights the capital intensity required to reach meaningful production volumes.
AmpliSi's £2 million pre-seed is a starting gun, not a finish line. The company will need substantially more funding to build pilot capacity, demonstrate material consistency at volume, and secure the kind of customer commitments that unlock further investment. The competitive landscape suggests that reaching commercial scale could require tens or hundreds of millions in additional capital—a reality that makes early execution milestones all the more critical.
Proving It at Scale
The immediate challenge is technical: Can the magnesiothermic process deliver consistent material performance batch after batch, at volumes that matter to battery manufacturers? Laboratory synthesis and industrial production are different disciplines, and the gap between them has claimed more than a few promising materials.
Then comes the commercial validation. Battery makers will want cycle-life data, safety testing, and proof that AmpliSi's silicon can survive the thermal and mechanical stresses of real-world use. They'll want assurance of supply, stable pricing, and evidence that integrating the material won't introduce new failure modes or production bottlenecks.
Those are table stakes. Meeting them would position AmpliSi for growth-stage funding and potential offtake agreements. Failing to meet them would relegate the company to the crowded graveyard of battery startups that couldn't bridge the gap between promising chemistry and commercial product.
For now, AmpliSi has capital, a differentiated process story, and backing from climate-focused investors with patience for deep-tech timelines. Whether that's enough will become clearer over the next 18 to 24 months, as the company moves from controlled laboratory conditions to the less forgiving environment of industrial scale-up.
The battery industry needs better anodes. Whether it needs AmpliSi's anodes specifically—and whether the company can deliver them at the right cost, quality, and volume—remains to be determined.
