Enhanced photo-assisted lithium-ion batteries using natural dye-impregnated LiFePO4 cathodes

Abstract

Photo-assisted lithium-ion batteries present a promising approach to integrating solar energy conversion and storage within a compact and efficient electrochemical system. However, their practical application is hindered by the scarcity of sustainable, low-cost, and photoactive electrode materials. In this study, the natural dye turmeric was successfully incorporated into LiFePO₄ cathodes via a simple solution-based method, yielding dual-functional electrodes with enhanced photoelectric and electrochemical properties. Under illumination, the resulting photo-battery exhibited improved photo-assisted charging, with charge and discharge capacities increasing by 9.9% and 7.7% at 0.5C, respectively. This performance enhancement is attributed to turmeric's efficient photon absorption, which facilitates improved charge transport and electron transfer under light exposure. Additionally, the composite electrode demonstrated excellent high-rate capability, delivering a discharge capacity of 104 mA h g⁻¹ at 5C. These results underscore the potential of natural, eco-friendly dyes as effective sensitizers for photo-assisted energy storage systems, offering a scalable, cost-effective, and environmentally sustainable pathway for next-generation energy storage technologies.