Organic-inorganic composite-derived mesoporous SiO2 and Si/SiC/C nanotubes applied in high-performance quasi-solid lithium-ion batteries

Abstract

BackgroundTo meet the market demanding of high-power safe secondary batteries, this work reported a new quasi-solid lithium-ion batteries (LIBs) technology. MethodsAn organic-inorganic composite was synthesized by sol-gel transcription method, then used as the starting material to prepare mesoporous SiO2 nanotubes (MSNTs) by calcinating and Si/SiC/C composite nanotubes (SSCNTs) by magnesiothermic reduction. The MSNTs were compounded with P(VDF-HFP) and lithium salt to produce a composite gel electrolyte (MSNTs-CGE) membrane, while the SSCNTs were used to make electrode. Significant findingsElectrochemical test showed that MSNTs-CGE exhibited wide electrochemical window (∼5.1 V), qualified ionic conductivity (1.0 × 10−3 S cm−1 at room temperature) and high lithium-ion transfer number (0.57). The assembled SSCNTs|MSNTs-CGE|Li battery showed a specific capacity up to 750 mA h g − 1 at a current density of 1 A g − 1 over 1000 cycles, stable Coulombic efficiency of no less than 99% and outstanding rate performance. The elaborately designed composition and structure similarity of the electrode and the electrolyte materials as well as their improved interfacial contact play important roles in the performance-enhancement of the LIBs.