Enthalpy-Entropy Modulation in Electrolyte Stabilizes 4.8 V-Class Li-Rich Mn-Based Cathodes
Yuhao Ma1, Shihong Qing1, Hongyu Liu1
1School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu, China.
Angewandte Chemie (International Ed. in English)
|July 30, 2026
Summary
Researchers developed a new electrolyte strategy for high-voltage lithium-rich manganese (LRM) cathodes. This approach improves battery cycling stability and fast-charging performance by optimizing ion interactions within the electrolyte.
Area of Science:
- Materials Science
- Electrochemistry
- Chemical Engineering
Background:
- Lithium-rich manganese (LRM) cathode materials offer high specific capacity for energy-dense batteries.
- High operating voltages of LRM cathodes (4.8 V vs. Li/Li+) lead to poor cycling stability in standard carbonate electrolytes.
Purpose of the Study:
- To design a novel electrolyte strategy for high-voltage LRM cathodes.
- To enhance cycling stability and fast-charging capabilities of LRM batteries.
Main Methods:
- Developed an "enthalpy-entropy modulation" strategy for electrolytes, guided by thermodynamic parameters.
- Weakened ion-solvent interactions to promote anion involvement (enthalpy modulation).
- Amplified disorder to increase configurational diversity (entropy modulation) in the solvation sheath.
Main Results:
- Reconfigured the solvation sheath to an anion-involved, diversified state, facilitating lithium-ion desolvation.
- Suppressed free solvent decomposition, forming a stable cathode-electrolyte interphase.
- Achieved extended cycle life (400 cycles, 76.6% retention at 1C) and excellent fast-charging (1068 cycles at 3C).
- Demonstrated stable cycling under high mass loading (20.1 mg cm-2 at 0.2C).
Conclusions:
- The "enthalpy-entropy modulation" strategy effectively stabilizes high-voltage LRM cathodes.
- This thermodynamically guided approach is crucial for developing next-generation electrolytes for advanced batteries.
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