The development of portable and wearable electronics has aroused the increasing demand for flexible energy‐storage devices, especially for the characteristics of high energy density, excellent mechanical properties, simple synthesis process, and low cost. However, the development of flexible electrodes for sodium‐ion batteries (SIBs) is still limited due to the intricate production methods and the relatively high‐cost of current collectors such as graphene/graphene oxide and carbon nanotubes. Here, the hierarchical 3D electronic channels wrapped large‐sized Na₃V₂(PO₄)₃ is designed and fabricated by a simple electrospinning technique. As flexible electrode material, it exhibits outstanding electrolyte wettability, together with ultrafast electronic conductivity and high Na‐ion diffusion coefficients for SIBs, leading to superior electrochemical performances. A high reversible specific capacity of 116 mA h g⁻¹ (nearly 99% of the theoretical specific capacities) can be obtained at the current density of 0.1 C. Even after a 300‐fold current density increased (30 C), the discharge specific capacity of the flexible electrode still remains 63 mA h g⁻¹. Such an effective concept of fabricating 3D electronic channels for large‐sized particles is expected to accelerate the practical applications of flexible batteries at various systems.

中文翻译：

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3D电子通道包裹了大型Na3V2（PO4）3作为钠离子电池的柔性电极

便携式和可穿戴电子产品的发展引起了人们对柔性储能设备的日益增长的需求，特别是对于高能量密度，出色的机械性能，简单的合成工艺和低成本的特性。但是，由于生产方法复杂以及集电器（如石墨烯/氧化石墨烯和碳纳米管）的成本较高，用于钠离子电池（SIB）的柔性电极的开发仍然受到限制。在此，分层3D电子通道包裹了大型Na ₃ V ₂（PO ₄）₃通过简单的静电纺丝技术进行设计和制造。作为柔性电极材料，它具有出色的电解质润湿性，以及超快的电子传导性和SIB的高Na离子扩散系数，从而具有出色的电化学性能。在0.1 C的电流密度下可获得116 mA hg ^-1的高可逆比容量（接近理论比容量的99％）。即使在300倍的电流密度增加（30 C）之后，放电比容量柔性电极的剩余部分仍保持63mA hg ^-1。这种为大尺寸颗粒制造3D电子通道的有效构想有望加速柔性电池在各种系统上的实际应用。