Solar energy is considered the most promising renewable energy source. Solar cells can harvest and convert solar energy into electrical energy, which needs to be stored as chemical energy, thereby realizing a balanced supply and demand for energy. As energy storage devices for this purpose, newly developed photo-enhanced rechargeable metal batteries, through the internal integration of photovoltaic technology and high-energy-density metal batteries in a single device, can simplify device configuration, lower costs, and reduce external energy loss. This review focuses on recent progress regarding the working principles, device architectures, and performances of various closed-type and open-type photo-enhanced rechargeable devices based on metal batteries, including Li/Zn-ion, Li-S, and Li/Zn-I₂, and Li/Zn-O₂/air, Li-CO₂, and Na-O₂ batteries. In addition to provide a fundamental understanding of photo-enhanced rechargeable devices, key challenges and possible strategies are also discussed. Finally, some perspectives are provided for further enhancing the overall performance of the proposed devices.

The urgent expectation of the next-generation energy storage devices for electric vehicles has driven researchers' attention to the lithium-oxygen (Li-O₂) batteries due to the satisfied specific energy density. Herein, spatially-controlled Co₃O₄ nanoflake arrays with three-dimensional- networked morphology are adopted as flexible and self-standing oxygen cathodes in Li-O₂ batteries. The spinel-phase Co₃O₄ nanoflakes were converted from two-dimension metal-organic frameworks with abundant available channels and large specific surface area. The open-structure nanoflake arrays possess sufficient Li₂O₂/cathode contact interface, great bifunctional catalytic performance and adequate Li₂O₂ accommodation, leading to the enhanced electrochemical performance of the Li-O₂ batteries. As expected, the binder-free porous Co₃O₄/CT cathode delivers a high capacity of 6, 509 mAh·g^-1 (200 mA·g^-1) and enhanced stability over 100 cycles (limited by 1, 000 mAh·g^-1). In addition, pouch-type Li-O₂ batteries were successfully designed and cycled with Co₃O₄/CT cathode as oxygen electrodes, demonstrating its potential application for flexible electronics and wearable energy storage devices.