Elucidating the Polymeric Binder Distribution within Lithium-Ion Battery Electrodes Using SAICAS

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Polymeric binder distribution in lithium-ion battery (LIB) electrodes critically impacts long-term electrochemical performance.
• Limited analytical tools have previously hindered in-depth analysis of binder distribution and its effects.

Purpose of the Study:

• To investigate the influence of drying temperature on polymeric binder distribution within LiCoO2 electrodes.
• To correlate binder distribution and adhesion properties with electrochemical performance, particularly at elevated temperatures.

Main Methods:

• Utilized a Surface and Interfacial Cutting Analysis System (SAICAS) to measure adhesion properties at various depths within LiCoO2 electrodes.
• Prepared electrodes dried at two different temperatures (130°C and 230°C) to observe the effects of thermal treatment.
• Evaluated electrochemical properties, specifically high-temperature cycling performance, of the prepared electrodes.

Main Results:

• Higher drying temperatures (230°C) resulted in binder and conductive agent accumulation near the electrode surface, altering depth-dependent adhesion.
• Electrodes dried at lower temperatures (130°C) exhibited more uniform adhesion properties throughout the depth.
• The LiCoO2 electrode dried at 130°C demonstrated superior high-temperature cycling performance compared to the one dried at 230°C.

Conclusions:

• Drying temperature significantly affects binder distribution and adhesion properties in LIB electrodes.
• Uniform adhesion and stronger interfacial adhesion, achieved at lower drying temperatures, are crucial for enhanced high-temperature electrochemical cycling performance.
• SAICAS is a valuable tool for analyzing electrode microstructures and optimizing battery design for demanding applications.