Composite polymer electrolyte based on poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) for solid-state...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Solid-state lithium-ion batteries (SSLIBs) offer enhanced safety over liquid electrolyte batteries.
• Achieving high ionic conductivity, low interface resistance, and electrode stability simultaneously in a single electrolyte is challenging.

Purpose of the Study:

• To develop a composite polymer electrolyte (CPE) membrane for SSLIBs.
• To improve electrochemical performance and stability by combining inorganic and organic components.

Main Methods:

• Prepared a composite polymer electrolyte membrane (CPE) using inorganic Li1.3Al0.3Ti1.7(PO4)3 (LATP) and organic poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) via casting.
• Investigated electrochemical performance using Li-Li symmetric cells and Li/CPE-10/NCM622 cells.

Main Results:

• The CPE membrane with 10 wt% LATP (CPE-10) showed a high ionic transference number (0.60) and electrochemical window (4.94 V).
• CPE-10 exhibited excellent Li-metal stability, enabling stable Li-Li symmetric cell operation for over 300 hours with dendrite inhibition.
• The Li/CPE-10/NCM622 cell achieved a specific discharge capacity of 152 mAh/g at 0.2C with 100% Coulombic efficiency over 50 cycles.

Conclusions:

• The developed CPE-10 provides a promising design strategy for high-performance SSLIBs.
• The composite approach effectively balances ionic conductivity, interface stability, and electrochemical performance.