Visualizing plating-induced cracking in lithium-anode solid-electrolyte cells

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Lithium dendrite propagation in ceramic electrolytes is a major obstacle for high-energy-density all-solid-state lithium-anode batteries.
• Short circuits caused by dendrites limit battery performance and safety at high charge rates.

Purpose of the Study:

• To investigate the mechanisms of crack and lithium dendrite propagation in ceramic electrolytes.
• To understand how these phenomena contribute to short-circuiting in all-solid-state batteries.

Main Methods:

• In situ X-ray computed tomography (XCT) was used to track crack propagation.
• Spatially mapped X-ray diffraction (XRD) was employed to monitor lithium dendrite behavior.
• Experiments were conducted on a Li/Li$_{6}$PS$_{5}$Cl/Li cell under varying charge conditions.

Main Results:

• Cracking initiates as spallations near the lithium electrode edges due to high local fields.
• Transverse cracks propagate across the electrolyte, driven by lithium ingress which widens the cracks.
• The cracks traverse the entire electrolyte before lithium reaches the other electrode, preceding a short circuit.

Conclusions:

• The study reveals that crack propagation precedes lithium dendrite penetration in Li$_{6}$PS$_{5}$Cl electrolytes.
• Understanding this crack-driving mechanism is crucial for designing safer and more efficient solid-state batteries.
• This finding offers insights into mitigating short circuits in next-generation lithium batteries.