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

Abstract 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 −1 after 200 cycles at 0.2 A g −1 , 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.