Stacking Pressure-Driven Interfacial Dynamics in Anode-Free Solid-State Lithium Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Stacking pressure is crucial for solid-state battery (SSB) performance, especially in anode-free configurations (AFSSBs).
• The specific impact of stacking pressure on anode and cathode interfaces in AFSSBs is not fully understood.

Purpose of the Study:

• To investigate how stacking pressure influences the electrochemical properties of anode and cathode interfaces in AFSSBs.
• To establish correlations between stacking pressure, interfacial characteristics, and lithium deposition behavior.

Main Methods:

• Experimental investigation of stacking pressure effects on AFSSB interfaces.
• Analysis of anode and cathode potentials, interface resistances, and lithium deposition morphology.
• Modeling of stress distribution within AFSSBs under varying pressures.

Main Results:

• Stacking pressure improves both anode and cathode interface properties, with a more pronounced effect on the anode.
• Increased stacking pressure correlates with higher reversible capacity, lower Li plating/stripping overpotentials, and more uniform Li deposition.
• Uniform Li deposition was identified as critical for minimizing the necessary stacking pressure.

Conclusions:

• Stacking pressure primarily benefits the anode interface in AFSSBs.
• Optimizing Li deposition uniformity can reduce the required stacking pressure for high-performance AFSSBs.
• This research provides insights into interfacial dynamics, enabling the development of SSBs that operate under lower stacking pressures.