Kinetical threshold limits in solid-state lithium batteries: Data on practical relevance of sand equation

Area of Science:

• Electrochemistry
• Materials Science
• Solid-State Batteries

Background:

• Poly (ethylene oxide)-based solid polymer electrolytes (PEO-based SPEs) are crucial for solid-state lithium metal batteries.
• Understanding the electrochemical behavior and limitations of these electrolytes is essential for battery performance.

Purpose of the Study:

• To investigate the practical relevance of the Sand equation for solid-state lithium metal batteries.
• To analyze the polarization onset and electrochemical response of PEO-based SPEs under various conditions.
• To correlate theoretical predictions with experimental data for PEO-based SPEs.

Main Methods:

• Utilized symmetric Li||Li cells in a three-electrode setup with a reference electrode.
• Investigated Sand behavior with varied negative electrodes and solid polymer electrolyte thicknesses.
• Examined electrochemical response, polarization onset (transition time), and Li salt concentration effects.
• Performed charge/discharge cycling using LiNi0.6Mn0.2Co0.2O2 (NMC622) as the positive electrode material.

Main Results:

• Experimental data supports the theoretical Sand equation for PEO-based solid polymer electrolytes.
• Identified polarization onset and transition times for various electrode configurations.
• Demonstrated the influence of SPE thickness and Li salt concentration on electrochemical performance.
• Provided discharge behavior data for NMC622 positive electrodes.

Conclusions:

• The Sand equation accurately predicts the behavior of PEO-based solid polymer electrolytes in lithium metal batteries.
• The study provides valuable data for optimizing solid-state battery design and performance.
• Experimental validation confirms the practical applicability of the Sand equation in this context.