Role of 1D and 2D Materials in Achieving Transparent and Flexible Lithium-Ion Batteries for Wearable Electronics

Transparent and flexible lithium-ion batteries (TFLIBs), enabled by advanced nanomaterials and flexible architectures, facilitate structural integration into electronic devices, significantly reducing overall size and weight. However, several obstacles remain for their practical deployment, particularly in balancing optical transparency, mechanical flexibility, and electrochemical performance. The development of transparent and flexible conductive materials has evolved through the combination of metals, metal oxides, and polymers. In this context, 1D and 2D nanomaterials have emerged as key enablers of lithium-ion battery technology. This review provides a mechanistic understanding of how 1D and 2D materials mitigate the fundamental trade-offs by optimizing the electrical conductivity of the electrode materials. Specifically, engineered 1D-2D hybrid architectures have significantly accelerated progress, in which delaminated 2D layers facilitate efficient ion transport, while interconnected 1D networks establish rapid electron-conduction pathways. Furthermore, advancements in solid-state electrolytes are discussed for improving device performance and stability. The fabrication strategies for TFLIBs are highlighted, with an emphasis on achieving a multifunctional balance among these characteristics for wearable electronics applications. Finally, this review highlights the challenges and future prospects and outlines high-performance material design strategies for TFLIBs.