Sulfur CAM: Drop-In for Existing Battery Plants

Gelion plc (AIM: GELN), the global energy storage innovator, is pleased to announce that the Company's Sulfur Cathode Active Material (CAM) has been successfully integrated into coin cells using standard lithium‑ion battery (LIB) and sodium‑ion battery (SIB) electrolytes and anodes. The potential of the Company's CAM is, therefore, demonstrated as a drop-in option for the globally-established GWh-scale manufacturing ecosystem.

Key Technical Achievements

• Function in mature cell architectures: Demonstrated compatibility with proven electrolyte, separator, and anode systems that dominate current global battery manufacturing (gigawatt‑hours per annum output).
• Drop-in potential with established LIB and SIB manufacturing: Potential for integration with established materials supply chains and manufacturing processes associated with the full spectrum of components used in GWh p.a. battery manufacture: anode, electrolyte, separator, cathode, casing.
• Unlocks standard LIB & SIB electrolyte use: Ability to use the same mature and cost‑efficient electrolytes trusted by battery manufacturers worldwide. Overcomes the industry‑wide incompatibility between conventional sulfur cathodes and carbonate‑solvent/hexafluorophosphate salt electrolytes. Compatibility with these established electrolyte systems is an essential requirement for an authentic drop-in supplement to established GWh p.a. manufacture and access to the associated market that this manufacture supplies (EV, ESS, personal devices, etc.).

Building upon successful transfer of the technology from the Max Planck Institute of Colloids and Interfaces (MPI) and CAM scale-up announced in September 2025, Gelion has successfully integrated its cathode technology into lithium-sulfur and sodium-sulfur coin cells that feature standard LIB or SIB components.

Specifically, Gelion has paired its Sulfur CAM with electrolyte systems based on carbonate-solvents and hexafluorophosphate salts which are ubiquitous in GWh p.a. LIB and SIB manufacture. Electrolytes based on these solvents and salts are advantaged in their ability to form passivating layers on the graphitic and hard-carbon anodes that underpin LIBs and SIBs, respectively.

Specifics of the tested cell architectures are listed in the table below:

1 The Gelion CAM is metalated (lithiated or sodiated) electrochemically in a Swagelok cell featuring the corresponding alkali-metal anode, prior to disassembly of the Swagelok cell, extraction of the cathode and incorporation of that cathode in a coin cell with components as listed in the table above.

Why This Breakthrough Matters

Conventional sulfur cathodes cannot be used with carbonate-solvents and hexafluorophosphate salts due to chemical incompatibilities that rapidly degrade components of both the electrolyte and sulfur cathode. Gelion's Sulfur CAM disconnects this incompatibility, allows the Company to revolutionise rather than replace gigafactory cell architectures. This compatability is a further advantage to the excellent power and longevity across lithium sulfur and sodium sulfur cathode technologies that have been previously announced by Gelion (August 2025 and April 2025, respectively).

Gelion will update on activities which focus on continued refinement of their Sulfur CAM for specific application with LIB electrolytes and anodes and SIB electrolytes and anodes, in addition to other commercial targets such as cathodes with industrially relevant areal capacity, and prototype cell development.

John Wood, CEO of Gelion, commented: "These results reflect Gelion's commitment to accelerating our battery technologies toward the broad market. We see and are working to deliver the potential for Sulfur CAM to become an ubiquitous option alongside LFP and NMC across the full range of battery applications for the energy transition (transportation and BESS). The results provide further traction with globally significant industrial players and the development of Gelion's relationship with those players, specifically with respect to the synergy of technology and commercial targets".

Sulfur Batteries

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