Formation of hierarchically ordered structures in conductive polymers to enhance the performances of lithium-ion batteries

Electrically conductive polymers have found increasing applications in energy conversion and storage devices. In the conventional design of conductive polymers, organic functionalities are introduced via bottom-up synthetic approaches to enhance specific properties by modification of the individual polymers. Unfortunately, the addition of functional groups leads to conflicting effects, limiting their scaled synthesis and broad applications. Here we show a conductive polymer with simple primary building blocks that can be thermally processed to develop hierarchically ordered structures (HOS) with well-defined nanocrystalline morphologies. Our approach to constructing permanent HOS in conductive polymers leads to substantial enhancement of charge transport properties and mechanical robustness, which are critical for practical lithium-ion batteries. Finally, we demonstrate that conductive polymers with HOS enable exceptional cycling performance of full cells with high-loading micron-size SiO_x-based anodes, delivering areal capacities of more than 3.0 mAh cm⁻² over 300 cycles and average Coulombic efficiency of >99.95%.