image: ITEN’s solid-state ceramic microbattery technology is used to develop a customized solution specifically designed to meet the smart lens requirements of XPANCEO.
Credit: XPANCEO
Lyon, France, and Dubai, UAE — XPANCEO, a deep-tech company pioneering smart contact lenses, and ITEN, a manufacturer of solid-state energy storage solutions, have developed a proof of concept for integrating a microbattery into a smart contact lens. The collaboration solves a main challenge in ocular wearables: making energy storage ultra-thin, durable, and stable enough to be safely used in devices worn directly on the human eye.
XPANCEO is developing smart contact lenses with AR and health monitoring capabilities as the ultimate computing platform for the AI era. Unlike AR glasses or VR headsets, a contact lens must deliver full functionality within a submillimetre-scale form factor and operate safely directly on the eye. This creates strict constraints on thickness, mass, heat generation, and material selection, with biocompatibility and user safety as critical requirements. Among other effects, these restrictions create a fundamental power challenge.
A fully featured smart contact lens requires different power levels for different tasks. Wireless connectivity and ultra-low-power functions, such as biosensing, can be supported by energy-harvesting mechanisms that capture small amounts of energy from the wearer’s body and immediate environment — including mechanical energy from blinking, thermal differences across the lens, electrochemical reactions with tear fluid, and integrated solar cells. However, high-energy functions, such as image projection for AR, require sustained milliwatt-level power. This makes high-density energy storage essential for full functionality.
In some ways, powering a smart contact lens is more difficult than powering implantable devices such as pacemakers. Implantable medical devices operate at very low power and typically use high-density lithium batteries, both non-rechargeable (primary) and rechargeable, enclosed in rigid, sealed housings usually made of titanium. In some long-lived implants, nuclear batteries have been used. A contact lens has no space for such shielding or rigid enclosures, making different safety and power approaches necessary.
Most existing energy-storage solutions are too bulky and volatile to be safely integrated into a soft, curved, ultra-thin contact lens. Lithium-ion cells can swell, leak, or overheat, making them unsafe for direct contact with the eye. Liquid-electrolyte batteries also carry risks of leakage or explosion if they fail. Even during normal operation, such batteries can release small amounts of hydrogen and can slightly expand in volume, particularly during initial cycles.
Solid-state batteries offer a promising solution since because they cannot leak, swell, or explode. If a failure occurs, the system simply stops supplying power. ITEN solutions can be engineered in ultra-thin, flexible formats compatible with soft contact-lens substrates, while still providing high enough power density for the short bursts of energy required by AR displays and wireless connectivity, without rapid degradation.
ITEN uses its specialized expertise in nanomaterial fabrication to produce fully ceramic electrodes with a patented mesoporous structure — meaning the material contains a network of extremely small, controlled pores. This structure significantly increases the electrode's surface area, so the device can deliver higher power and charge and discharge more efficiently. Since May 2025, ITEN has been mass-producing the first generation of solid-state ceramic microbatteries that offer an unrivaled mix of power density, recharge speed, safety, and reliability. This technology is employed to develop a customized microbattery specifically designed to meet the smart-lens specifications of XPANCEO.
During the first stage of the ITEN–XPANCEO collaboration, engineers solved critical integration challenges involving the design of a multi-stage encapsulation process. They developed a dedicated energy harvester for optimal operation with dynamically changing wireless links. They also examined critical thermal and overvoltage considerations relevant to battery operation in the electromagnetically and mechanically dense environment of a contact lens.
Solid-state energy storage is still in the early stages of adoption, with a limited number of companies that are capable of producing miniature and high-efficiency cells in high volume. The ITEN–XPANCEO proof of concept demonstrates that high-power-density energy storage can now be manufactured in volume production and safely integrated into a contact lens, marking a crucial milestone in making smart contact lenses commercially viable.
“The power system is the real bottleneck in smart contact lens development — and it’s not something you fix with small tweaks. We needed a whole new approach to energy storage at the micro-scale. Working with ITEN, we tackled challenges that had no precedent. Our partnership isn’t focused on adapting existing technology but on creating entirely new categories of components that the supply chain doesn’t produce yet. That’s the challenge, and the opportunity, as we move toward commercialization,” says Dr. Valentyn Volkov, founder and CTO of XPANCEO, recognized among the top 2% of scientists worldwide.
“By combining ITEN’s solid-state energy storage technology with cutting-edge smart lens innovation, the ITEN partnership with XPANCEO opens a new frontier in compact, high-power energy solutions. Together, we are enabling a new generation of intelligent and highly integrated systems that demand both performance and reliability — delivering power where space is limited and expectations are high, with the added assurance of full safety enabled by inherently stable, non-flammable product architecture,” says Vincent Cobée, CEO of ITEN.