ProLogium Says Its 381 Wh/kg Gen 3.5 Solid-State Cell Is Now in Mass Production in Taiwan

ProLogium says its 185.4 Ah Gen 3.5 Lithium Ceramic Battery large-format cell is now in mass production at the company's Giga-level manufacturing facility in Taiwan.¹ That makes the Sept. 2 announcement a manufacturing-stage story, not just another laboratory solid-state-battery result.

The headline performance figure also comes with an important sourcing qualifier. ProLogium says a third-party TÜV test report measured the cell at 381 Wh/kg gravimetric energy density and 903 Wh/L volumetric energy density.¹ The underlying TÜV report was not independently inspected by this newsroom, so those numbers remain ProLogium's account of the third-party test rather than independently verified newsroom measurements.¹

Those are also cell-level figures. They do not by themselves establish pack-level energy density, vehicle range, fast-charging time, cost, production yield or the performance of a finished EV battery pack.¹

Mass production is not the same as a production EV

The biggest distinction is what ProLogium's announcement does not yet establish. Reviewed public materials do not identify a production passenger EV using this exact 185.4 Ah Gen 3.5 cell as its traction battery.¹² That is a bounded public-record check, not a claim that no private or undisclosed vehicle program exists.

ProLogium and OPmobility announced a memorandum of understanding in June to evaluate possible integration of ProLogium solid-state cells into EV battery modules and packs, with potential future OEM adoption.² The companies described an evaluation and development relationship, not a production-vehicle award or proof that this Gen 3.5 cell has completed OEM qualification.²

That gap matters because mass-produced cell, automotive-qualified battery and battery deployed in a production vehicle are separate commercialization milestones. The Sept. 2 announcement advances the manufacturing stage; the reviewed evidence does not collapse the later stages into the same event.¹²

This is not ProLogium's first mass-production claim

ProLogium has been making commercial-production claims for years. In May, the company said it had been commercially manufacturing its Lithium Ceramic Battery platform since 2013 and had shipped more than 2.4 million cells in total, including more than 800,000 third-generation cells from its Taiwan Giga-level plant.³ Its current company materials say the Taoyuan GWh-class facility began operating in 2024.⁴

So the new part is narrower than ProLogium has started mass-producing solid-state batteries. The company says the higher-energy-density Gen 3.5 large-format design has now entered mass production on an already operating manufacturing platform.¹³⁴

For EV buyers, the next consequential evidence would be more specific: independently inspectable test documentation, Gen 3.5 production-rate or yield data, a named traction-battery customer, completed OEM qualification, or a production vehicle using the cell. None of those should be inferred from the Sept. 2 mass-production announcement alone.¹²

Sources

Footnotes

1. “ProLogium Begins Mass Production of High-Energy-Density All-Solid-State Battery, Reaching 381 Wh/kg and 903 Wh/L” — ProLogium Technology / GlobeNewswire distribution, Sept. 2, 2026. https://via.ritzau.dk/pressemeddelelse/15131436/prologium-technology-co-ltd?publisherId=90446 Establishes ProLogium's current Gen 3.5 mass-production statement, the 185.4 Ah specification and its description of the TÜV result. The underlying factory-output data and TÜV report were not independently inspected by the newsroom. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

2. “ProLogium and OPmobility Sign MoU to develop next generation Solid-State Battery Modules for Mobility” — ProLogium Technology / OPmobility, June 9, 2026. https://prologium.com/prologium-and-opmobility-sign-mou-to-develop-next-generation-solid-state-battery-modules-for-mobility/ Establishes the MoU to evaluate possible solid-state module/pack integration for EV applications and potential OEM adoption; it is not a production contract or completed vehicle qualification. ↩ ↩² ↩³ ↩⁴ ↩⁵

3. “ProLogium, a Next Generation Solid-State Battery Developer with 10+ Years of Proven Commercialization, to List on the Nasdaq through a Merger with Translational Development Acquisition Corp.” — ProLogium Technology, May 27, 2026. https://prologium.com/prologium-a-next-generation-solid-state-battery-developer-with-10-years-of-proven-commercialization-to-list-on-the-nasdaq-through-a-merger-with-translational-development-acquisition-corp/ Establishes ProLogium's company-reported commercial-manufacturing history and cumulative shipment figures. ↩ ↩²

4. “About ProLogium” — ProLogium Technology, observed Sept. 2, 2026. https://prologium.com/about/ Establishes the company's current description of the Taoyuan GWh-class facility entering operation in 2024 and its manufacturing history. ↩ ↩²