Stabilizing the oxide cathode/sulfide solid electrolyte interface via a novel polyaniline coating prepared by ball...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Oxide cathode/sulfide solid electrolyte (SSE) interfaces exhibit thermodynamic instability, causing high interfacial resistance in all-solid-state lithium-ion batteries (ASSLIBs).
• This instability hinders the performance and cycle life of ASSLIBs, a promising next-generation energy storage technology.

Purpose of the Study:

• To develop a strategy for stabilizing the lithium cobalt oxide (LCO)/SSE interface in ASSLIBs.
• To investigate the use of a flexible polyaniline (PANI) coating as an alternative to rigid lithium-containing oxides for interface stabilization.

Main Methods:

• A flexible polyaniline (PANI) coating was prepared on the LCO cathode via a facile ball milling and annealing process.
• Electrochemical tests were conducted to evaluate the interfacial resistance and cycling performance of ASSLIBs with the PANI-coated LCO cathode and Li5.5PS4.5Cl1.5 solid electrolyte.

Main Results:

• The elastic PANI coating effectively lowered the interfacial resistance between the LCO cathode and the SSE.
• The PANI layer maintained low interfacial resistance throughout the cycling process.
• ASSLIBs incorporating the PANI-coated LCO cathode demonstrated high capacity retention of 85.5% after 200 cycles.

Conclusions:

• Flexible polyaniline coatings are a viable strategy to mitigate interfacial instability in oxide cathode/SSE interfaces for ASSLIBs.
• The PANI coating enhances the electrochemical performance and cycling stability of ASSLIBs by reducing interfacial resistance.