Electrochemically Tuned Crystal Tectonics in Crack-Resistant Textured Oxide Cathode Films for Electrochemical Energy...

Area of Science:

• Materials Science
• Electrochemistry
• Crystallography

Background:

• Ceramic battery electrode performance is significantly affected by electro-chemo-mechanical degradation.
• Degradation pathways are strongly influenced by bulk crystallographic texture, crystal size, and interfacial misorientation.
• Controlling these microstructural features is crucial for enhancing battery longevity.

Purpose of the Study:

• To demonstrate the deterministic synthesis of textured thick LiCoO₂ films with controlled microstructures via electrodeposition.
• To investigate the relationship between crystallographic texture, interfaces, and degradation pathways.
• To develop strategies for chemomechanical stabilization of battery electrodes.

Main Methods:

• Electrodeposition was used to synthesize LiCoO₂ films with varying textures and microstructures.
• Growth parameters (current density, temperature, supersaturation) were controlled to achieve specific crystal morphologies.
• Electron backscatter diffraction (EBSD) and Raman spectroscopy were employed for microstructural and degradation analysis.

Main Results:

• ⟨110⟩||ND textured films with finer crystallites and Σ3 twin boundaries were synthesized under kinetic growth conditions.
• ⟨003⟩||ND films with coarser crystals and high-angle crystal interfaces (HACIs) formed under thermodynamic growth conditions.
• ⟨003⟩||ND electrodes degraded via intercrystal and intracrystal cracking (13.3% retention), while ⟨110⟩||ND electrodes showed only intercrystal cleavage (89.2% retention), with CSL boundaries remaining robust.

Conclusions:

• The crystallographic orientation and interfacial structure critically influence the degradation modes of ceramic battery electrodes.
• Controlled synthesis of textured films with specific boundaries (e.g., Σ3 CSL) enhances chemomechanical stability.
• Orchestrating microstructure offers a pathway to unique stabilization strategies for advanced battery materials.