Composite Solid Electrolytes Inhibit Dendrite Penetration for Stable All-Solid-State Lithium Batteries Revealed by 3D...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• All-solid-state lithium metal batteries (ASSLBs) face challenges with lithium dendrite penetration, causing short circuits and failure.
• Current Li6PS5Cl (LPSC) solid electrolytes are susceptible to dendrite growth, limiting practical applications.

Purpose of the Study:

• To develop a composite solid electrolyte interlayer to suppress lithium dendrite growth in LPSC-based ASSLBs.
• To enhance the mechanical strength and ionic conductivity for improved battery cycling stability.

Main Methods:

• Fabrication of a Li10GeP2S12-Li6PS5Cl (LGPS-LPSC) composite solid electrolyte interlayer.
• Electrochemical testing of Li|Li symmetric and Li|LiCoO2 full cells.
• Characterization using 3D and in situ 2D electron paramagnetic resonance (EPR) imaging and nanoindentation.

Main Results:

• LGPS-LPSC composite electrolyte effectively blocked lithium dendrite penetration.
• Li|Li symmetric cells operated stably for 2000 hours at 0.5 mA cm-2.
• Li|LiCoO2 full cells retained 69.51% capacity after 900 cycles at 1 C, demonstrating enhanced cycling stability.

Conclusions:

• The LGPS-LPSC composite electrolyte enhances mechanical strength to physically block dendrites.
• It also optimizes ionic conductivity pathways for uniform lithium plating, improving ASSLB performance and longevity.