An Elastomeric Lithium-Conducting Interlayer for High-Performance LATP-Based Lithium Metal Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Lithium metal batteries face challenges with interfacial impedance and volume changes.
• Solid-state electrolytes like Li(1+x)Al(x)Ti(2-x)(PO4)3 (LATP) require effective buffer layers.
• Existing interlayers often lack the necessary elasticity and stability.

Purpose of the Study:

• To develop an elastomeric lithium-conducting interlayer to address LATP battery limitations.
• To improve interfacial stability and accommodate volume changes in lithium metal batteries.
• To enhance the overall performance and cycle life of LATP-based batteries.

Main Methods:

• Fabrication of a fluorinated hydrogenated nitrile butadiene rubber (F-HNBR) matrix.
• Utilizing vulcanization, vapor-phase fluorination, and plasticization for interlayer synthesis.
• Integrating the F-HNBR interlayer into LATP-based lithium symmetric and full cells.

Main Results:

• The F-HNBR interlayer demonstrated high elasticity (423%), fatigue resistance (10,000 cycles), and ionic conductivity (6.3 × 10^-4 S cm^-1).
• LATP-based symmetric cells achieved 1600 h of stable cycling at 0.1 mA cm^-2 and deep cycling at 0.5 mAh cm^-2.
• Full cells exhibited 500 cycles with 98.3% capacity retention and supported high-mass-loading cathodes (11.1 mg cm^-2) at room temperature.

Conclusions:

• The F-HNBR interlayer effectively mitigates interfacial issues in LATP lithium metal batteries.
• This flexible, robust interlayer significantly enhances battery cycle life and stability.
• The developed interlayer enables high-performance, room-temperature operation of advanced lithium metal batteries.