Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin , Austin, Texas 78712, United States.
Nano Lett. 2013 Jul 10;13(7):3414-9. doi: 10.1021/nl401880v. Epub 2013 Jun 20.
Silicon is considered one of the most promising anode materials for high-performance Li-ion batteries due to its 4200 mAh/g theoretical specific capacity, relative abundance, low cost, and environmental benignity. However, silicon experiences a dramatic volume change (∼300%) during full charge/discharge cycling, leading to severe capacity decay and poor cycling stability. Here, we report a three-dimensional (3D) ternary silicon nanoparticles/conducting polymer/carbon nanotubes hybrid anode material for Li-ion batteries. The hierarchical conductive hydrogel framework with carbon nanotubes as the electronic fortifier offers a continuous electron transport network and high porosity to accommodate the volume expansion of Si particles. By 3D wrapping of silicon nanoparticles/single-wall carbon nanotubes with conducting polymer nanostructures, a greatly improved cycling performance is achieved with reversible discharge capacity over 1600 mAh/g and 86% capacity retention over 1000 cycles at the current rate of 3.3 A/g. Our findings represent a new direction for fabricating robust, high-performance lithium-ion batteries and related energy storage applications with advanced nanostructured materials.
硅因其 4200 mAh/g 的理论比容量、相对丰富的资源、低廉的成本和环境友好性而被认为是最有前途的高容量锂离子电池负极材料之一。然而，硅在完全充放电循环过程中经历剧烈的体积变化（~300%），导致严重的容量衰减和较差的循环稳定性。在此，我们报道了一种用于锂离子电池的三维（3D）三元硅纳米颗粒/导电聚合物/碳纳米管杂化负极材料。具有碳纳米管作为电子增强剂的分层导电水凝胶骨架提供了连续的电子传输网络和高孔隙率，以容纳 Si 颗粒的体积膨胀。通过将硅纳米颗粒/单壁碳纳米管用导电聚合物纳米结构进行 3D 包裹，实现了优异的循环性能，在 3.3 A/g 的电流速率下，可逆放电容量超过 1600 mAh/g，循环 1000 次后容量保持率为 86%。我们的研究结果为利用先进的纳米结构材料制造坚固、高性能的锂离子电池和相关储能应用提供了一个新的方向。
