Constructing Garnet Electrolytes with Internal 3-D Electronic Insulation Network for Dendrite-Free Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Batteries

Background:

• Garnet-type solid-state lithium metal batteries (SSLMBs) offer high energy density and safety but suffer from lithium dendrite penetration.
• Lithium dendrites compromise battery integrity and operational lifespan.

Purpose of the Study:

• To enhance the dendrite-suppressing ability of garnet-type electrolytes for practical SSLMB applications.
• To improve the safety and cycling stability of solid-state lithium metal batteries.

Main Methods:

• Fabrication of a composite electrolyte using garnet-type Li6.4La3Zr1.4Ta0.6O12 (LLZTO) and a glass electrolyte (50Li2O-38B2O3-12SiO2, LBS).
• Construction of a 3-D continuous electronic insulation network at LLZTO grain boundaries using LBS.
• Electrochemical testing of Li|LLZTO-LBS|Li symmetric cells and Li|LLZTO-LBS|LiFePO4 full cells.

Main Results:

• The composite electrolyte demonstrated a high critical current density of 1.1 mA cm-2.
• Stable lithium plating/stripping was achieved for over 1000 hours at 0.2 mA cm-2 in symmetric cells.
• Full cells exhibited a high initial specific capacity of 141.8 mA h g-1 and stable cycling for over 100 cycles.

Conclusions:

• The LLZTO-LBS composite electrolyte effectively suppresses lithium dendrite growth by creating an electronic insulation network.
• This novel electrolyte design significantly improves the safety and electrochemical performance of solid-state lithium metal batteries.