Dendrite formation in solid-state batteries arising from lithium plating and electrolyte reduction

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Batteries

Background:

• All-solid-state batteries promise high energy density and eco-friendliness.
• Lithium metal anodes in these batteries are hindered by dendrite formation, impeding commercialization.

Purpose of the Study:

• To elucidate the distinct mechanisms of dendrite formation in lithium/lithium lanthanum zirconium oxide/lithium solid-state batteries.
• To provide insights for mitigating dendrite-related challenges in solid-state energy storage.

Main Methods:

• Utilized non-invasive techniques: solid-state nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI).
• Employed tracer-exchange NMR to analyze Li plating and Li+ reduction at interfaces and grain boundaries.
• Applied in situ MRI to observe real-time dendrite growth dynamics.

Main Results:

• Identified two primary dendrite formation mechanisms: rapid non-uniform Li plating and sluggish bulk Li+ reduction.
• Observed localized Li+ reduction at Li7La3Zr2O12 grain boundaries.
• Revealed a period of stalled dendrite growth between the two mechanisms.

Conclusions:

• Dendrite formation in solid-state batteries is complex, influenced by amorphous/crystalline dendrites, solid electrolyte defect chemistry, and operating conditions.
• This study deepens the fundamental understanding of dendrite growth in solid-state lithium batteries.
• Findings offer valuable insights for developing strategies to suppress dendrite formation and enhance battery safety and performance.