Multi-Dimensional Optimized Interfaces with Rich Hydrogen-Bond Networks in Composite Solid Electrolytes for...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Composite solid electrolytes (CSEs) are crucial for advanced batteries, but efficient lithium-ion (Li+) transport remains a challenge.
• Current CSEs often suffer from slow Li+ transport due to polymer chains and suboptimal organic-inorganic interfaces.
• Weak interfacial interactions and inefficient interface construction hinder overall Li+ conductivity in existing materials.

Purpose of the Study:

• To achieve interface-dominated Li+ transport in ultracompatible CSEs.
• To enhance Li+ conductivity and transference number in solid-state electrolytes.
• To develop design principles for practical applications of inorganic cluster chains (ICCs) in batteries.

Main Methods:

• Modification of sub-1 nm inorganic cluster chains (ICCs) with polyether amine (PEA) to create ultracompatible CSEs.
• Utilizing abundant amino groups in PEA for ICC monodispersity and hydrogen bonding with polymer chains (PVDF-HFP).
• Optimizing multidimensional interfaces to amplify organic-inorganic interfaces and interfacial hydrogen bonds, regulating polymer chain orientation.

Main Results:

• Achieved dominant Li+ interface transport (52%) through enhanced interfacial interactions and regulated polymer chain orientation.
• Developed CSEs with exceptional room temperature ionic conductivity (0.53 mS cm-1).
• Demonstrated a substantial Li+ transference number (0.65) and stable cycling performance (95% capacity retention in NCM/Li batteries after 500 cycles).

Conclusions:

• Interface engineering by modifying ICCs with PEA is a key strategy for dominant Li+ interface transport in CSEs.
• The developed CSEs exhibit excellent electrochemical performance, paving the way for practical battery applications.
• This work provides critical insights into ICC utilization and design principles for advanced composite solid electrolytes.