Polymeric Backbone Eutectogel Electrolytes for High-Energy Lithium-Ion Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Developing advanced solid-state electrolytes is crucial for high-energy lithium-ion batteries (LIBs).
• Ensuring electrochemical compatibility with commercially relevant cathode materials is a key challenge for practical LIB applications.

Purpose of the Study:

• To introduce and characterize a novel polymeric backbone eutectogel (P-ETG) hybrid solid-state electrolyte.
• To evaluate the electrochemical compatibility of the NIPAM-based P-ETG with nickel-rich LiNi_0.6Mn_0.2Co_0.2O₂ (NMC622) cathodes.

Main Methods:

• Synthesis and characterization of the NIPAM-based P-ETG electrolyte.
• Electrochemical testing including cyclic voltammetry and galvanostatic cycling.
• Physicochemical analyses: Fourier transform infrared spectroscopy, powder X-ray diffraction, and elemental analysis.

Main Results:

• The NIPAM-based P-ETG demonstrated excellent chemical and electrochemical compatibility with NMC622.
• No interfacial reactions, unchanged crystallographic composition, and no transition metal leaching were observed.
• The electrolyte exhibited a wide electrochemical stability window (1.5-5.0 V) and good ionic conductivity (0.82 mS cm^-1).
• Li|P-ETG|NMC622 cells showed stable cycling performance with high Coulombic efficiency (>95%).

Conclusions:

• The NIPAM-based P-ETG is a promising solid-state electrolyte for high-energy LIBs utilizing NMC622 cathodes.
• Understanding electrolyte-electrode compatibility is vital for the practical application of advanced battery materials.
• This work provides insights into designing stable interfaces for next-generation LIBs.