Batteries with water-based electrolytes offer more energy using new cathode

Researchers from The Hong Kong Polytechnic University and Shenzhen University have developed a novel cathode material, K⁺ and C3N4 co-intercalated NH4V4O10 (KNVO-C3N4), for aqueous zinc-ion batteries that significantly enhances energy density, cycling stability, and performance across a wide temperature range. This cathode features expanded interlayer spacing and increased oxygen vacancies, which improve structural integrity and reduce electrostatic interactions between Zn2+ ions and the vanadate layers. The synergistic co-intercalation of potassium ions and C3N4 lowers the Zn2+ diffusion barrier, resulting in improved reaction kinetics and battery performance even under extreme temperatures from –20 °C to 60 °C. The KNVO-C3N4 cathode demonstrates excellent electrochemical properties, including a high rate performance of 228.4 mAh g⁻¹ at 20 A g⁻¹, long-term cycling stability with 174.2 mAh g⁻