Magnetic and Optical Field Multi-Assisted Li-O2 Batteries with Ultrahigh Energy Efficiency and Cycle Stability

The photoassisted lithium-oxygen (Li-O-2) system has emerged as an important direction for future development by effectively reducing the large overpotential in Li-O-2 batteries. However, the advancement is greatly hindered by the rapidly recombined photoexcited electrons and holes upon the discharging and charging processes. Herein, a breakthrough is made in overcoming these challenges by developing a new magnetic and optical field multi-assisted Li-O-2 battery with 3D porous NiO nanosheets on the Ni foam (NiO/FNi) as a photoelectrode. Under illumination, the photogenerated electrons and holes of the NiO/FNi photoelectrode play a key role in reducing the overpotential during discharging and charging, respectively. By introducing the external magnetic field, the Lorentz force acts oppositely on the photogenerated electrons and holes, thereby suppressing the recombination of charge carriers. The magnetic and optical field multi-assisted Li-O-2 battery achieves an ultralow charge potential of 2.73 V, a high energy efficiency of 96.7%, and good cycling stability. This external magnetic and optical field multi-assisted technology paves a new way of developing high-performance Li-O-2 batteries and other energy storage systems.

Automated summary

The study developed a new magnetic and optical field multi-assisted Li-O-2 battery by adding 3D porous NiO nanosheets to the photoelectrode, effectively reducing the overpotential in Li-O-2 batteries. Under illumination, the generated electrons and holes played a key role in reducing the overpotential during discharging and charging. The introduction of an external magnetic field suppressed charge carrier recombination. This technology provides a new approach to developing high-performance Li-O-2 batteries and other energy storage systems.