Catenaa, Saturday, February 21, 2026- Scientists at The Hong Kong University of Science and Technology have developed a high-performance calcium-ion battery that could offer a sustainable alternative to lithium-ion technology for clean energy storage.
The research team integrated quasi-solid-state electrolytes into calcium-ion batteries, aiming to improve ionic conductivity and long-term stability. The findings were published in Advanced Science in November 2025.
Calcium-ion batteries are seen as a potential successor to lithium-ion systems due to calcium’s abundance and comparable electrochemical window. However, challenges in ion transport and cycling stability have slowed commercial development. The HKUST team addressed these barriers by designing redox-active covalent organic framework electrolytes that create structured pathways for calcium ions.
Laboratory tests showed ionic conductivity of 0.46 millisiemens per centimeter and strong calcium ion transport at room temperature. A full battery cell delivered a reversible specific capacity of 155.9 milliampere-hours per gram at 0.15 amperes per gram. At higher current density, the battery retained more than 74% of its capacity after 1,000 charge and discharge cycles.
Researchers said the structured alignment of carbonyl groups within the framework enables faster ion movement and greater operational stability. The project was conducted in collaboration with Shanghai Jiao Tong University.
As global demand for renewable energy storage and electric vehicles grows, the development may expand options beyond lithium-based systems and support long-term energy security
