In Situ Light-Modulation of Capacity and Impedance in Lithium-Ion Batteries.

The in situ regulation of capacity and impedance presents a significant challenge that impedes the application of lithium-ion batteries (LIBs). Herein, a novel strategy is introduced that utilizes a broadband light-modulated method for in situ manipulation of cell capacities and impedances. This approach leverages a photoconductive heterojunction comprising cadmium sulfide (CdS) nanorod arrays and a reduced graphene oxide (rGO) film. The heterostructure efficiently responds to a broad light spectrum, including UV to visible wavelengths. The results show that for the CdS/rGO anode, under conditions of UV exposure and absence of illumination, the capacity varies between 275 and 450 mAh g after 200 cycles at 0.2 A g, and the impedance changes from 1205 to 261 Ω, respectively. When applied to a full-cell, the capacity and impedance of the full-cell can still be controlled by light intensity and light type. The facts suggest that by constructing light-modulated devices, in situ modulation of battery capacity and impedance can be successfully achieved, facilitating the application of LIBs in complex scenarios. This important innovation offers a novel approach to battery design and holds immense potential for developing safer and more efficient energy storage systems.