The headline number is $75 million. The money actually committed is about $22 million. And the factory that number is meant to transform is operated by a South Korean manufacturer, not Amprius.

Amprius Technologies, the silicon-anode battery maker, entered into a new agreement with the U.S. government on Sept. 23, according to a Form 8-K filed with the Securities and Exchange Commission. The company followed on Sept. 28 with a press release titled "Amprius Secures $75 Million Grant for American High-Energy Density Battery Production." Read side by side, the two documents describe a real and strategically useful deal for the small-drone supply chain. They also show that the word "grant" is doing a lot of work.

What the Filing Says

According to the 8-K, the vehicle is an Other Transaction Agreement for what the document calls Project acCELLerate, issued under 10 U.S.C. 4022. Its aim is domestic, high-energy-density pouch-cell production that complies with Section 842 of the National Defense Authorization Act, for Group 1, 2 and 3 small unmanned aircraft systems.

The key terms, all from the filing:

  • Value: up to $75 million, described as the entire U.S. Government share. No cost share is required from Amprius.
  • Structure: fixed-price, with payments tied to milestones and made after the government accepts deliverables.
  • Period: a base period running Sept. 23, 2026 to Sept. 22, 2028.
  • Obligated funds: approximately $22 million, using fiscal 2025 research, development, test and evaluation (RDT&E) funding.
  • Exit clause: the agreement can be terminated for convenience on 30 days' notice, and it carries restrictions on foreign participation.

In other words, roughly $22 million is on the table today. The balance of the $75 million is a ceiling rather than a balance in an account.

Whose Line Is It?

Amprius's press release says the award comes from the U.S. Department of War through the IBAS program. The money is to retrofit an existing domestic EV battery line operated by a major South Korean manufacturer, which the company does not name. Completion is planned for early 2028, with capacity of 12 million cells a year.

The release puts the conversion cost at about $100 million, including in-kind investments from Amprius and its partner. That is a notable detail given the filing's statement that no cost share is required: the government's share tops out at $75 million, and DroneXL reports that Amprius and its partner are covering the rest in kind. The release also notes that Amprius's global supply network spans China, South Korea and the United States.

CEO Tom Stepien framed the goal in the release as establishing "a primary source of domestic, NDAA-compliant battery production."

The Funding Gap

DroneXL reported that the company's own announcement says a majority of the award remains unfunded and subject to future appropriations. The roughly $22 million obligated is under a third of the headline figure.

That distinction matters because of how the deal was presented publicly. On CNBC, Stepien described the award as a $75 million grant. He also said on CNBC that the 12 million cells would translate to about $150 million in incremental annual revenue, against 2026 revenue guidance of at least $140 million, according to DroneXL. The revenue claim depends on the line being completed and on customers buying its output. Completion depends on milestone payments, and most of those payments are not yet funded.

A Change of Plan

The Korean-partner model follows a retreat from a very different plan. DroneXL, citing Manufacturing Dive, reports that Amprius cancelled a $190 million factory in Brighton, Colorado in June 2025 and paid $20 million to exit the lease. The Department of Energy had selected the company for a $50 million grant tied to that effort.

Stepien's description of the new approach on CNBC, as quoted by DroneXL, was blunt: "We're not pouring concrete, we're not putting steel up." Instead of building a plant, Amprius is converting someone else's. DroneXL also reports that Stepien said the company still has cells made in China and that he and many customers are happy with their cost and production.

The arrangement also builds on earlier steps. Manufacturing Dive noted a manufacturing agreement between Amprius and Nanotech Energy, per a Feb. 3 press release, for domestic silicon-anode cell production to meet NDAA sourcing restrictions.

Why It Matters

Battery supply is one of the hardest constraints on a non-Chinese small-drone industry. Prepared Senate testimony said Drone Dominance Phase II would ban systems using batteries or motors from covered countries, DroneXL reports, and Stepien said on the August earnings call that about half of the 19 drone makers invited to the Fort Carson demonstration use Amprius cells. A compliant, high-energy-density cell source at scale would address a real chokepoint for those builders. Amprius's Defense Innovation Unit battery contract now totals $18.1 million, per the same report.

But the structure of this award argues for caution. Only about $22 million is obligated. Payment is milestone-based and follows acceptance of deliverables. The government can walk away on 30 days' notice. The production line is operated by a South Korean manufacturer, and the work is to be done within restrictions on foreign participation that the filing does not detail. None of that makes the project implausible, but it means the 12-million-cell, early-2028 target is a plan contingent on future appropriations, not a funded outcome.

For drone makers weighing supply decisions, the practical reading is that domestic, NDAA-compliant silicon-anode capacity has a credible path and a first tranche of federal money, not a guarantee.

What to Watch

  • Whether future appropriations cover the unfunded balance of the $75 million.
  • Whether Amprius or the Department of War identifies the South Korean manufacturer.
  • Milestone acceptances during the base period ending Sept. 22, 2028, against a planned early-2028 completion.
  • How the company reconciles the "grant" language in its headline with the obligated amount in its filings.

Sources