Self-charging power systems integrating energy harvesting technologies and batteries are attracting extensive attention. However, conventional integrated systems are highly dependent on energy source availability and have complicated configurations. This study develops chemically self-charging aqueous zinc-ion batteries with a simplified two-electrode configuration based on CaV₆O₁₆·3H₂O electrode. This system simultaneously harvests, converts, and stores energy. It chemically self-recharges via the spontaneous redox reaction between the discharged cathode and ambient oxygen. The batteries display an initial open-circuit voltage of ~1.05 V and a discharge capacity of ~239 mAh g⁻¹, demonstrating excellent self-rechargeability and functionality in chemical or galvanostatic charging hybrid modes. This work provides a route for designing self-charging energy storage and broadens the scope of aqueous zinc-ion batteries.

Yan Zhang, Fang Wan, Shuo Huang, Shuai Wang, Zhiqiang Niu, Jun Chen