Swallowing Lithium Dendrites in All-Solid-State Battery by Lithiation with Silicon Nanoparticles

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium dendrite growth is a major obstacle to the performance and safety of all-solid-state lithium batteries (ASSLBs).
• Effective strategies are needed to suppress uncontrolled lithium deposition and dendrite propagation within solid electrolytes.

Purpose of the Study:

• To propose and demonstrate a novel strategy for inhibiting lithium dendrite growth in ASSLBs.
• To enhance the cycling stability and safety of ASSLBs by managing lithium anode behavior.

Main Methods:

• Incorporation of silicon nanoparticles into solid polymer electrolytes (SPEs) to interact with lithium dendrites.
• Fabrication of a sandwich-structured solid electrolyte (LLZO-PEO/Si-PEO/LLZO-PEO).
• Electrochemical testing of Li/LiFePO4 cells with the novel solid electrolyte, including plating/stripping and cycling stability assessments.

Main Results:

• Silicon nanoparticles effectively lithiate with adjacent lithium dendrites, inhibiting their formation and growth.
• Demonstrated stable lithium plating/stripping for over 1800 hours.
• Achieved improved cycling stability in Li/LiFePO4 cells with a reversible capacity of 111.9 mAh g⁻¹ at 1C after 150 cycles.
• Pouch cells showed comparable cyclic stability and flexibility, indicating practical applicability.

Conclusions:

• The proposed strategy of using lithiated silicon nanoparticles in solid electrolytes is a simple and effective method to control lithium dendrite growth.
• This approach significantly enhances the performance and safety of all-solid-state lithium batteries.
• The flexible and stable pouch cells suggest promising applications in next-generation energy storage devices.