A Paradigm Shift in Anode-Free Lithium Metal Battery: Pressure-Activated Solid-State Interfaces for High-Rate...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Anode-free lithium metal batteries (AF-LMBs) offer superior energy density compared to traditional batteries but face challenges like lithium dendrite growth and inventory depletion.
• These issues are amplified in larger-scale pouch cells, hindering practical application.

Purpose of the Study:

• To develop a multiscale interfacial strategy to address the core limitations of AF-LMBs.
• To enhance the stability and performance of AF-LMBs, particularly in Ah-scale pouch cells.

Main Methods:

• Few-layer lithium montmorillonite nanosheets were produced and integrated with polyacrylamide gel, forming a functionalized composite separator (FMT-Li/PAM-PE).
• This composite separator was applied to a copper substrate modified with recycled spent graphite (SGR-Cu).
• The assembled 1.0 Ah pouch cell utilized a LiNi0.8Co0.1Mn0.1O2 cathode.

Main Results:

• The composite separator exhibited high mechanical strength (204.4 MPa), thermal stability, and anion screening capability (t+ = 0.78).
• The strategy established a solid-state Li+ diffusion pathway, mitigating solvated Li+ interactions and improving interfacial adhesion.
• The 1.0 Ah pouch cell achieved 81.1% capacity retention over 200 cycles, with energy densities of 453.3 Wh kg-1 / 1183.2 Wh L-1 and power output of 1045.0 W kg-1.

Conclusions:

• The multiscale interfacial strategy effectively suppresses dendrite formation and lithium depletion in AF-LMBs.
• This approach enables high-rate cation diffusion and unlocks the potential for commercial AF-LMB prototyping across various cell configurations.