Lv Dan, Yang Lili, Song Runfeng, Yuan Hongyan, Luan Jingyi, Liu Jie, Hu Wenbin, Zhong Cheng
Key Laboratory of Advanced Ceramics and Machining Technology (Ministry of Education), School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China.
Key Laboratory of Advanced Ceramics and Machining Technology (Ministry of Education), School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China.
J Colloid Interface Sci. 2025 Jan 15;678(Pt B):336-342. doi: 10.1016/j.jcis.2024.09.009. Epub 2024 Sep 5.
Silicon (Si) is considered as one of the most potential commercial materials for the next-generation lithium-ion batteries (LIBs) owing to its high theoretical capacity and low voltage platform. However, the severe volume expansion and poor electric conductivity of Si anodes limit the practical application. Herein, a hierarchical porous hard carbon@Si@soft carbon (PHC@Si@SC) material was prepared by a chemical vapor deposition (CVD) and following calcination process. The differences in capacities and initial Coulombic efficiencies (ICEs) resulting from variations in silane deposition are demonstrated using PHC@Si as a model. To improve the cycling performance, a cheap pitch-derived soft carbon was introduced to protect the nano-Si to suppress the volume expansion. The formed PHC@Si@SC anode delivers a high capacity of 1625 mAh g and a high ICE of 86.8%, attributed to the excellent cooperation of hard and soft carbon. The capacity retention is 55% after 100 cycles with a harsh N/P ratio of 1.1 in a PHC@Si@SC||NCM811 full cell. This work provides a strategy, which is easy to scale up for practical application.
硅（Si）因其高理论容量和低电压平台，被认为是下一代锂离子电池（LIBs）最具潜力的商用材料之一。然而，硅阳极严重的体积膨胀和较差的导电性限制了其实际应用。在此，通过化学气相沉积（CVD）和后续煅烧工艺制备了一种分级多孔硬碳@硅@软碳（PHC@Si@SC）材料。以PHC@Si为模型，展示了硅烷沉积变化导致的容量和初始库仑效率（ICEs）差异。为了提高循环性能，引入了一种廉价的沥青衍生软碳来保护纳米硅以抑制体积膨胀。所形成的PHC@Si@SC阳极具有1625 mAh g的高容量和86.8%的高ICE，这归因于硬碳和软碳的出色协同作用。在PHC@Si@SC||NCM811全电池中，在苛刻的N/P比为1.1的情况下，经过100次循环后容量保持率为55%。这项工作提供了一种易于扩大规模以用于实际应用的策略。
