Interplay of Dynamic Constriction and Interface Morphology between Reversible Metal Anode and Solid Electrolyte in...

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Electrical contact and interface stability are crucial for all-solid-state battery performance.
• Impedance spectroscopy is a key technique for non-destructively analyzing interfaces.
• Correlating microscopic processes with macroscopic impedance signals remains a challenge.

Purpose of the Study:

• To systematically investigate the effect of electrode/sample interface morphology on impedance spectra.
• To understand the contributions of charge transfer and geometric constriction to interface impedance.
• To analyze the origin and characteristics of constriction phenomena in battery interfaces.

Main Methods:

• Utilized a 3D electric network model to simulate interface behavior.
• Systematically varied electrode/sample interface morphologies in the model.
• Analyzed the resulting impedance spectra to identify key contributing factors.

Main Results:

• Interface impedance arises from both charge transfer and geometric constriction.
• Geometric constriction, caused by non-ideal contacts like pores, affects the electrochemical active surface area dynamically.
• Constriction effects are dominant in systems with low charge transfer resistance, such as garnet electrolytes with lithium metal anodes.

Conclusions:

• Interface morphology significantly dictates the impedance response of all-solid-state batteries.
• Understanding geometric constriction is vital for accurate impedance interpretation and battery design.
• This model provides insights into microscopic processes relevant for reversible metal anodes.