In Situ Construction of Functional Customized Elastic Li⁺ Conducting Interlayer for High-Performance Garnet-Type...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Solid-state lithium metal batteries (SSLMBs) face challenges in lithium metal volumetric fluctuations, Li+ transport, and dendrite growth, hindering commercialization.
• Effective interfacial engineering is crucial for overcoming these limitations in SSLMBs.

Purpose of the Study:

• To design and implement a multifunctional elastic interlayer for enhancing the performance and stability of SSLMBs.
• To investigate the role of phytic acid (PA) in interfacial modification for improved Li+ diffusion and dendrite suppression.

Main Methods:

• Fabrication of a multifunctional elastic interlayer incorporating phytic acid macromolecules.
• Characterization of the interlayer's mechanical properties and its effect on Li+ transport.
• Analysis of the solid electrolyte interphase (SEI) layer formed on the lithium metal anode.
• Electrochemical testing of lithium symmetric cells and pouch cells with high-loading NCM83 cathodes.

Main Results:

• The phytic acid interlayer effectively buffered volume changes during lithium deposition/stripping.
• Anion-rich solvation and a stable SEI layer (rich in LiF and LixPO4) were formed.
• The lithium symmetric cell achieved a high critical current density (CCD) of 4.6 mA cm-2 and stable cycling for over 500 hours at 1.0 mA cm-2.
• The pouch cell demonstrated a discharge capacity of 3.18 mAh cm-2 after 35 cycles with a high-loading NCM83 cathode.

Conclusions:

• The developed elastic interlayer strategy significantly improves Li+ transport and suppresses dendrite growth in SSLMBs.
• The interfacial engineering approach enhances the cycling stability and critical current density of lithium metal anodes.
• This strategy shows promising practical potential for the commercialization of high-performance SSLMBs.