Lithium metal batteries represent promising candidates for high-energy-density batteries, however, many challenges must still be overcome,e.g., interface instability and dendrite growth. In this work, nano silica aero...Lithium metal batteries represent promising candidates for high-energy-density batteries, however, many challenges must still be overcome,e.g., interface instability and dendrite growth. In this work, nano silica aerogel was employed to generate a hybrid film with high lithium ion conductivity(0.6 mS cm^(-1)at room temperature) via an in situ crosslinking reaction. TOF-SIMS profile analysis has revealed conversion mechanism of hybrid film to Li–Si alloy/Li F biphasic interface layer, suggesting that the Li–Si alloy and Li F-rich interface layer promoted rapid Li+transport and shielded the Li anodes from corrosive reactions with electrolyte-derived products. When coupled with nickel-cobalt-manganese-based cathodes, the batteries achieve outstanding capacity retention over 1000 cycles at 1 C. Additionally the developed film coated on Li enabled high coulombic efficiency(99.5%) after long-term cycling when coupled with S cathodes. Overall, the results presented herein confirm an effective strategy for the development of high-energy batteries.展开更多
采用杂化密度泛函B3LYP理论,对Si_5及Li原子修饰的Si_5团簇的几何结构和电子性质及储氢性能进行了研究。结果表明:Si_5团簇最低能量构型为笼型结构,纯笼型Si_5团簇不能有效地吸附氢分子;Li原子的修饰可以显著改善其储氢能力,在两个Li原...采用杂化密度泛函B3LYP理论,对Si_5及Li原子修饰的Si_5团簇的几何结构和电子性质及储氢性能进行了研究。结果表明:Si_5团簇最低能量构型为笼型结构,纯笼型Si_5团簇不能有效地吸附氢分子;Li原子的修饰可以显著改善其储氢能力,在两个Li原子端位修饰Si_5笼型团簇体系中,其氢分子的平均吸附能为7.259~11.330 k J/mol,每个Li原子周围可以有效吸附5个氢分子,储氢质量分数达11.554%。因此,Li修饰Si_5笼型团簇体系有望成为理想的储氢材料。展开更多
基金the support from National Natural Science Foundation of China (22179006)International Science & Technology Cooperation Program of China under Contract No.2019YFE0100200+3 种基金National Natural Science Foundation of China (52072036)NSAF (No.U1930113)Guangdong Key Laboratory of Battery Safety,China (No.2019B121203008)China Postdoctoral Science Foundation (No.2021TQ0034)。
文摘Lithium metal batteries represent promising candidates for high-energy-density batteries, however, many challenges must still be overcome,e.g., interface instability and dendrite growth. In this work, nano silica aerogel was employed to generate a hybrid film with high lithium ion conductivity(0.6 mS cm^(-1)at room temperature) via an in situ crosslinking reaction. TOF-SIMS profile analysis has revealed conversion mechanism of hybrid film to Li–Si alloy/Li F biphasic interface layer, suggesting that the Li–Si alloy and Li F-rich interface layer promoted rapid Li+transport and shielded the Li anodes from corrosive reactions with electrolyte-derived products. When coupled with nickel-cobalt-manganese-based cathodes, the batteries achieve outstanding capacity retention over 1000 cycles at 1 C. Additionally the developed film coated on Li enabled high coulombic efficiency(99.5%) after long-term cycling when coupled with S cathodes. Overall, the results presented herein confirm an effective strategy for the development of high-energy batteries.
文摘采用杂化密度泛函B3LYP理论,对Si_5及Li原子修饰的Si_5团簇的几何结构和电子性质及储氢性能进行了研究。结果表明:Si_5团簇最低能量构型为笼型结构,纯笼型Si_5团簇不能有效地吸附氢分子;Li原子的修饰可以显著改善其储氢能力,在两个Li原子端位修饰Si_5笼型团簇体系中,其氢分子的平均吸附能为7.259~11.330 k J/mol,每个Li原子周围可以有效吸附5个氢分子,储氢质量分数达11.554%。因此,Li修饰Si_5笼型团簇体系有望成为理想的储氢材料。
