Thick electrodes are appealing for high energy density devices but succumb to sluggish charge transfer kinetics and poor mechanical stability. Nanomaterials with large aspect ratio, such as carbon nanotubes, can help improve the charge transfer and strength of thick electrodes but represent a costly solution which hinders their utility outside of “lab scale production.” Here, a conductive nanofiber network with decoupled electron and ion transfer pathways by the conformal electrostatic assembly of neutral carbon black particles on negatively charged cellulose nanofibers is reported. After integrating with lithium iron phosphate (LFP), the conductive nanofiber network enables a compact and high‐loaded (up to 60 mg cm⁻²) electrode with robust electrical networks and shortened ion transport paths. The interconnected nanopores inherited from the conductive network function as nanosized electrolyte reservoirs surrounding the electroactive materials and acting as ion‐conducting highways across the electrode. Based on the compact electrode structure and fast charge transfer kinetics, flexible Li‐LFP batteries with outstanding areal capacity and volumetric energy density (8.8 mAh cm⁻² and 538 Wh L⁻¹) are developed, substantially exceeding conventional LFP‐based batteries. Given the low cost raw materials together with the scale up processability, the conductive nanofiber design provides a promising strategy toward high‐performance energy storage devices.

中文翻译：

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导电纤维素纳米纤维启用的厚电极，用于紧凑和灵活的储能设备

厚电极吸引了高能量密度的设备，但屈服于缓慢的电荷转移动力学和较差的机械稳定性。具有长宽比的纳米材料，例如碳纳米管，可以帮助改善厚电极的电荷转移和强度，但代表了一种昂贵的解决方案，阻碍了它们在“实验室规模生产”之外的应用。在此，报道了通过中性炭黑颗粒在带负电荷的纤维素纳米纤维上的共形静电组装而具有解耦的电子和离子传递路径的导电纳米纤维网络。与磷酸铁锂（LFP）集成后，导电纳米纤维网络可实现紧凑，高负载（高达60 mg cm ^-2））电极，具有强大的电气网络并缩短了离子传输路径。从导电网络继承的相互连接的纳米孔起着围绕电活性材料的纳米级电解质储存器的作用，并充当跨电极的离子导电通道。基于紧凑的电极结构和快速的电荷转移动力学，开发了具有出色的面容量和体积能量密度（8.8 mAh cm ^-2和538 Wh L ^-1）的柔性Li-LFP电池，大大超过了传统的基于LFP的电池。考虑到低成本的原材料以及可扩展的可加工性，导电纳米纤维设计为高性能储能设备提供了一种有前途的策略。