Lithium (Li) metal is a promising anode for the next generation high-energy–density batteries. However, the growth of Li dendrites, low coulombic efficiency and dramatic volume change limit its development. Here, we ...Lithium (Li) metal is a promising anode for the next generation high-energy–density batteries. However, the growth of Li dendrites, low coulombic efficiency and dramatic volume change limit its development. Here, we report a new synthetic poly-dioxolane (PDOL) approach to constructing an artificial 'elastic' SEI to stabilize the Li/electrolyte interface and the Li deposition/dissolution behavior in a variety of electrolytes. By coating PDOL with optimized molecular weights and synthetic routes on Li metal anode, the 'elastic' SEI layer could be maintained on top of the Li metal anode to accommodate the Li deposition/dissolution. No dendrite formation was observed during the cycling process, and the interfacial side reactions were reduced significantly. Consequently, we successfully achieved 330 cycles with a CE of 98.4% in ether electrolytes and 90 cycles with a CE of 94.3% in carbonate electrolytes. Simultaneously, the Li-metal batteries with LiFePO_(4) as cathodes also exhibited improved cycling performance. This strategy could promote the development of dendrite-free metal anodes toward high-performance Li-metal batteries.展开更多
Gel polymer electrolytes(GPEs)are one of the promising candidates for high-energy-density quasi-solid-state lithium metal batteries(QSSLMBs),for their high ionic conductivity and excellent interfacial compatibility.Th...Gel polymer electrolytes(GPEs)are one of the promising candidates for high-energy-density quasi-solid-state lithium metal batteries(QSSLMBs),for their high ionic conductivity and excellent interfacial compatibility.The comprehension of dynamic evolution and structure-reactivity correlation at the GPE/Li interface becomes significant.Here,in situ electrochemical atomic force microscopy(EC-AFM)provides insights into the LiNO_(3)-regulated micromechanism of the Li plating/stripping processes upon cycles in GPE-based LMBs at nanoscale.The additive LiNO_(3)induces the formation of amorphous nitride SEI film and facilitates Li^(+) ion diffusion.It stabilizes a compatible interface and regulates the Li nucleation/growth at steady kinetics.The deposited Li is in the shape of chunks and tightly compact.The Li dissolution shows favorable reversibility,which guarantees the cycling performance of LMBs.In situ AFM monitoring provides a deep understanding into the dynamic evolution of Li deposition/dissolution and the interphasial properties of tunable SEI film,regulating the rational design of electrolyte and optimizing interfacial establishment for GPE-based QSSLMBs.展开更多
基金This research was supported financially by the Major Program of the National Natural Science Foundation of China(21890731).
文摘Lithium (Li) metal is a promising anode for the next generation high-energy–density batteries. However, the growth of Li dendrites, low coulombic efficiency and dramatic volume change limit its development. Here, we report a new synthetic poly-dioxolane (PDOL) approach to constructing an artificial 'elastic' SEI to stabilize the Li/electrolyte interface and the Li deposition/dissolution behavior in a variety of electrolytes. By coating PDOL with optimized molecular weights and synthetic routes on Li metal anode, the 'elastic' SEI layer could be maintained on top of the Li metal anode to accommodate the Li deposition/dissolution. No dendrite formation was observed during the cycling process, and the interfacial side reactions were reduced significantly. Consequently, we successfully achieved 330 cycles with a CE of 98.4% in ether electrolytes and 90 cycles with a CE of 94.3% in carbonate electrolytes. Simultaneously, the Li-metal batteries with LiFePO_(4) as cathodes also exhibited improved cycling performance. This strategy could promote the development of dendrite-free metal anodes toward high-performance Li-metal batteries.
基金financially supported by the National Key R&D Program of China(Grant No.2016YFA0202500)the National Natural Science Fund for Excellent Young Scholars(Grant No.21722508)。
文摘Gel polymer electrolytes(GPEs)are one of the promising candidates for high-energy-density quasi-solid-state lithium metal batteries(QSSLMBs),for their high ionic conductivity and excellent interfacial compatibility.The comprehension of dynamic evolution and structure-reactivity correlation at the GPE/Li interface becomes significant.Here,in situ electrochemical atomic force microscopy(EC-AFM)provides insights into the LiNO_(3)-regulated micromechanism of the Li plating/stripping processes upon cycles in GPE-based LMBs at nanoscale.The additive LiNO_(3)induces the formation of amorphous nitride SEI film and facilitates Li^(+) ion diffusion.It stabilizes a compatible interface and regulates the Li nucleation/growth at steady kinetics.The deposited Li is in the shape of chunks and tightly compact.The Li dissolution shows favorable reversibility,which guarantees the cycling performance of LMBs.In situ AFM monitoring provides a deep understanding into the dynamic evolution of Li deposition/dissolution and the interphasial properties of tunable SEI film,regulating the rational design of electrolyte and optimizing interfacial establishment for GPE-based QSSLMBs.
