Compliant Solid Polymer Electrolytes (SPEs) for Enhanced Anode-Electrolyte Interfacial Stability in All-Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Lithium-metal batteries (LMBs) offer high energy density but face challenges with dendrite formation and unstable electrodeposition.
• Solid polymer electrolytes (SPEs) can mitigate dendrite growth, but optimizing network structures for stable lithium metal anodes remains difficult.

Purpose of the Study:

• To design and investigate novel comb-chain cross-linker-based network SPEs with tunable compliance.
• To enhance anode-electrolyte interfacial contact and stable electrodeposition behavior in LMBs through modified SPE architectures.

Main Methods:

• Synthesized network SPEs incorporating free dangling chains to tune ionic conductivity, ductility, and compliance.
• Evaluated SPE performance in Li|SPE|Li symmetric cells and Li|SPE|LiFePO4 half cells under various cycling conditions.

Main Results:

• Increased SPE network compliance and ductility improved anode-electrolyte interfacial adhesion and reduced voltage hysteresis.
• SPEs with 56.3 wt% free dangling chains achieved 93.4% Coulombic efficiency and 1.9x longer cycle life in symmetric cells.
• Half-cell cycling demonstrated reduced interfacial resistance growth and 92.8% capacity retention after 275 cycles at 1C.

Conclusions:

• Introducing free dangling chains into network SPEs is an effective strategy to enhance lithium metal anode performance.
• Tunable SPE compliance and ductility are crucial for stable lithium metal battery operation and extended cycle life.