High-Charge Density Polymerized Ionic Networks Boosting High Ionic Conductivity as Quasi-Solid Electrolytes for...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Solid-state electrolytes are crucial for safer energy storage, particularly in lithium metal rechargeable batteries.
• Current solid-state electrolytes suffer from lower ionic conductivity compared to liquid electrolytes, hindering battery performance.
• Achieving ionic conductivity comparable to liquid electrolytes is a primary goal for solid-state electrolyte development.

Purpose of the Study:

• To design and synthesize novel solid-state electrolytes with high ionic conductivity and electrochemical stability.
• To investigate the potential of high-charge density polymerized ionic networks inspired by poly(ionic liquid)s.
• To evaluate the performance of these electrolytes in lithium metal rechargeable batteries.

Main Methods:

• Synthesis of high-charge density polymerized ionic networks.
• Measurement of ionic conductivity at room temperature (25 °C).
• Determination of electrochemical stability and decomposition potential.
• Assembly and testing of Li/LiFePO4 and Li/LiCoO2 battery cells.

Main Results:

• A quasi-solid electrolyte achieved an ionic conductivity of 5.89 × 10⁻³ S cm⁻¹ at 25 °C, surpassing existing polymer electrolytes.
• The electrolyte exhibited an ultrahigh decomposition potential exceeding 5.2 V versus Li/Li⁺.
• Assembled Li/LiFePO4 and Li/LiCoO2 batteries demonstrated high stable capacities of approximately 155 and 130 mAh g⁻¹, respectively.

Conclusions:

• The developed polymerized ionic networks offer a promising pathway for high-performance solid-state electrolytes.
• Continuous ion transport channels and enhanced chemical stability contribute to the superior properties.
• This work advances the design and fabrication of solid-state electrolytes for diverse energy conversion devices.