Accelerated Selective Li+ Transports Assisted by Microcrack-Free Anionic Network Polymer Membranes for Long Cyclable...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Rechargeable lithium metal batteries offer high energy density for electric vehicles and grid storage.
• Safety concerns and short cycle life due to lithium dendrites and solid-electrolyte interphase hinder their application.
• Developing stable and efficient electrolytes is crucial for advancing lithium metal battery technology.

Purpose of the Study:

• To create microcrack-free anionic network polymer membranes for enhanced lithium metal battery performance.
• To address safety issues and improve cycle life by suppressing lithium dendrite formation.
• To investigate the properties and effectiveness of tethered borate anions in polymer electrolytes.

Main Methods:

• A facile one-step click reaction was employed to synthesize microcrack-free anionic network polymer membranes.
• The membranes were characterized for cation conductivity, electrochemical stability window, and dendrite resistance.
• Performance of lithium metal batteries utilizing these membranes was evaluated at high temperatures over 450 cycles.

Main Results:

• The synthesized membranes exhibited high cation conductivity (3.1 × 10^-5 S cm^-1) at high temperatures.
• They demonstrated a wide electrochemical stability window (up to 5 V) and outstanding non-flammability.
• The membranes showed remarkable resistance to dendrite growth, leading to high capacity retention (92.7%) and coulombic efficiency (99.867%) over 450 cycles.

Conclusions:

• Microcrack-free anionic network polymer membranes with tethered borate anions effectively suppress lithium dendrite growth.
• These membranes enable safe and long-lasting operation of lithium metal batteries at high temperatures.
• The developed membranes represent a significant advancement for high-energy density battery applications.