4 December 2025

Gelion plc
("Gelion", the "Company" or the "Group")

 Technical Breakthrough: Gelion Achieves Target Areal Capacity

Gelion Advanced Sulfur Cathodes Reach Key Industry Milestone in Coin Cells

Gelion plc (AIM: GELN), the global energy storage innovator, has achieved a major technical milestone in the development of its next-generation sulfur battery technology. This achievement marks a major step forward in Gelion's roadmap to delivering high-energy-density, low-cost sulfur-based batteries suitable for e-aviation, electric mobility, stationary storage, and other commercial applications.

In this next phase of development, Gelion confirms that its proprietary cathode active material ("Gelion CAM") has crossed the 4Q threshold demonstrating stable cycling with the industry recognised 4Q areal capacity (~4 mAh/cm²) in coin cells, the industry standard platform for evaluating new battery materials. Achieving 4Q is widely regarded as a key milestone for high energy density sulfur cathodes. This demonstrates that Gelion CAM can be processed into thicker, high structural integrity electrodes which provide a critical step towards high energy density performance in large format pouch cells. This is a critical enabler for scaling sulfur-based technology toward commercial grade battery systems.

Building on the successful technology transfer from the Max Planck Institute of Colloids and Interfaces (MPI) and the Gelion CAM scale-up announced in September 2025, recent electrode development work shows that Gelion's proprietary material can maintain mechanical stability and controlled porosity even at increased thickness. Achieving these properties is critical to reaching industrially relevant high-areal-capacity electrodes and represents an important benchmark for competitiveness with conventional lithium-ion technology.

Historically, increasing sulfur loading in battery electrodes has been limited by rapid degradation of thicker electrodes. Gelion's results indicate that its CAM can overcome these limitations, supporting higher energy per square centimetre while maintaining electrode robustness, a key pathway toward smaller, lighter, and higher-energy battery cells.

Achieving 4Q areal capacity is a core technical requirement for large-format Li-S and Na-S cells and directly supports Gelion's energy-density and cost objectives for next-generation sulfur-based batteries.

Key Highlights:

John Wood, CEO of Gelion, commented: "Achieving 4Q areal capacity in coin cells marks a major validation of our sulfur cathode platform and represents a key technical milestone for Gelion. In the battery industry, 4Q is widely recognised as an important benchmark for high-energy-density sulfur cathodes, and these results give us strong confidence that our sulfur CAM can progress toward delivering the same performance in pouch-cell formats. As we continue refining electrodes for larger format manufacturing, we are building the technical foundation required for prototype development and industry engagement."

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About Gelion

Gelion ("gel: ion") is a global energy storage innovator, supporting the transition to a more sustainable economy by commercialising globally important next generation battery technologies: Sulfur based, Lithium-Sulfur (Li-S), Sodium-Sulfur (Na-S) and Zinc-based (Zn) hybrid cells to electrify mobile and stationary applications and battery recycling technology.

Gelion plc (the Group) is listed on the London Stock Exchange's Alternative Investment Market and wholly owns UK based OXLiD Ltd and Battery Minerals Ltd and Australia based Gelion Technologies Pty Ltd.  Gelion is designing and delivering innovative battery technology to enable that transition and return value for its customers and investors.

In addition, Gelion is also delivering commercial Battery Energy Storage Systems (BESS) projects through its Integration Solutions business.

Sulfur Batteries

Gelion's effort is directed at the potential for sulfur-based cathode active materials (CAMs) to deliver low-cost & sustainable batteries with compelling performance. In the case of Li-S batteries, the target is a high-performance light-weight battery for the EV and e-aviation market. In the case of Na-S batteries, the target is an ultra-low-cost advancement on batteries currently employed in the stationary storage and economy EV market. The company's overarching goal is to help make global transport, energy consumption and storage more sustainable.

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