Carbon Shells and Carbon Nanotubes Jointly Modified SiOx Anodes for Superior Lithium Storage

作者：Hang Zhou, Hang Zhou, Bin Yang, Haiping Zhou, Haiping Zhou, Chang Liu, Shu Zhang, Tingting Feng, Ziqiang Xu, Zixuan Fang, Jian Gao, Mengqiang Wu · 发表于：ACS Applied Energy Materials · 年份：2024 · DOI：10.1021/acsaem.4c01513 · 被引用次数：14 · 研究领域：Advancements in Battery Materials、Advanced Battery Materials and Technologies、Extraction and Separation Processes

Micron-sized silicon oxide (SiO x ) is a preferred solution for the new generation lithium-ion battery anode materials owing to the advantages in energy density and preparation cost. Nonetheless, its limited conductivity coupled with significant volume expansion results in structural instability and a swift decline in capacity. Herein, low-pressure chemical vapor deposition (LPCVD) and spray drying were employed to construct a composite anode material with a dual conductive carbon coating encapsulating silicon oxide (SiO x @C@CNTs). LPCVD-derived carbon coatings can substantially reduce the volumetric variations in SiO x, leading to the formation of a stable solid electrolyte interphase layer on its surface. Then, the carbon nanotube (CNT) conductive network can provide a fast transmission channel for charge exchange. Consequently, the SiO x @C@CNTs anodes have excellent cycling stability (624.7 mAh g –1 after 1000 cycles at 2 A g –1 ) and rate performance (790.3 mAh g –1 reversible lithium storage capacity at 4 A g –1 ). When paired with NCM811 cathode materials in full cells (SiO x @C@CNTs/G∥NCM811), these anodes provide a substantial energy density of 401.8 Wh kg –1 coupled with a stable cycling performance, achieving 134.8 mAh g –1 after 100 cycles at a rate of 1 C, with a capacity retention rate of 80.7%.