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Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
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Cathode-Electrolyte Interphase of Ni-Rich Layered Oxides: Evolving Structure and Implication on Stability.
Menghao Li1,2, Xuming Yang3, Xianbin Wei1,2
1Eastern Institute for Advanced Study, Eastern Institute of Technology, Ningbo, Zhejiang 315200, P. R. China.
Nano Letters
|February 11, 2025
Summary
This study reveals atomic-level details of the cathode-electrolyte interphase (CEI) using cryo-TEM. Understanding CEI structure is key to improving battery performance and longevity.
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- The cathode-electrolyte interphase (CEI) is critical for battery performance but its structure and function are poorly understood.
- Existing knowledge on CEI is limited and often debated, hindering battery development.
Purpose of the Study:
- To visualize atomic-resolution CEI structures using cryogenic transmission electron microscopy (cryo-TEM).
- To investigate the dynamic evolution of CEI during battery cycling.
- To correlate CEI structure with battery performance.
Main Methods:
- Utilized cryogenic transmission electron microscopy (cryo-TEM) for atomic-resolution imaging.
- Employed Ni-rich oxide (LiNi0.8Co0.1Mn0.1O2, NCM811) microparticles as a model cathode.
- Analyzed CEI formation and evolution in ethylene carbonate (EC) and fluoroethylene carbonate (FEC) based electrolytes.
Main Results:
- Achieved unprecedented high-resolution images of CEI structures.
- Observed distinct CEI formations: amorphous organic-rich layer in EC-electrolytes and LiF-rich grains in FEC-electrolytes.
- Documented CEI thickening and different structural evolutions (mosaic vs. dual-layer) with cycling.
Conclusions:
- Cryo-TEM is effective for revealing atomic-resolution CEI structures.
- CEI structure dynamically evolves with cycling and differs based on electrolyte composition.
- This research provides crucial insights into CEI dynamics, addressing controversies and guiding future battery design.
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