An anisotropic strategy for developing polymer electrolytes endowing lithium metal batteries with...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Solid polymer electrolytes are crucial for safe lithium metal batteries.
• Challenges include nonuniform lithium deposition, slow ion kinetics, and poor mechanical strength.

Purpose of the Study:

• To develop an anisotropic solid polymer electrolyte for improved lithium metal battery performance.
• To enhance lithium-ion flux, suppress dendrite growth, and create a stable electrode interface.

Main Methods:

• Integration of polymer hosts with oriented polyacrylonitrile nanofibers modified by Li6.4La3Zr1.4Ta0.6O12 particles.
• Fabrication of an anisotropic composite structure.
• Electrochemical testing of Li||LiFePO4 cells.
• Numerical modeling and density functional theory (DFT) analysis.

Main Results:

• The anisotropic structure homogenized Li+ flux and acted as a physical barrier against lithium dendrites.
• Reduced side reactions between the electrolyte and lithium metal.
• Achieved stable cycling over 1000 cycles with 91% capacity retention at 170 mA g-1 in Li||LiFePO4 cells.
• Clarified the multiphysics interplay at the electrolyte-electrode interface.

Conclusions:

• The designed anisotropic solid polymer electrolyte offers a compatible interface for lithium metal anodes.
• This approach provides a viable strategy for constructing interface-friendly solid polymer electrolytes for advanced batteries.
• Highlights the importance of electrochemo-mechanical design for battery performance.