Investigation of Ionic Conductivity of Electrolytes for Anode-Free Lithium-Ion Batteries by Impedance Spectroscopy
Anode-free lithium-ion batteries offer a volumetric energy density approximately 60% higher than that of conventional lithium-ion cells. Despite this advantage, they often experience rapid capacity degradation and a limited cycle life. Optimizing electrolyte formulations—particularly through the use...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-05-01
|
| Series: | Electrochem |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2673-3293/6/2/20 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Anode-free lithium-ion batteries offer a volumetric energy density approximately 60% higher than that of conventional lithium-ion cells. Despite this advantage, they often experience rapid capacity degradation and a limited cycle life. Optimizing electrolyte formulations—particularly through the use of specific additives, solvents, and lithium salts—is essential to improving these systems. This study explores electrolytes composed of fluorinated and carbonate-based solvents applied in anode-free lithium-ion cells featuring copper as the anode substrate and Li<sub>1.05</sub>Ni<sub>0.33</sub>Mn<sub>0.33</sub>Co<sub>0.33</sub>O<sub>2</sub> as the cathode. In the present work, the ionic conductivity of electrolytes was studied by impedance spectroscopy, and the electrochemical parameters of anode-free lithium-ion cells were compared using these electrolyte solutions: lithium difluoro(oxalato)borat (LIDFOB) salts were used in a mixture of solvents such as fluoroethylene carbonate (FEC) and dimethoxyethane (DME) in a ratio of 3:7 and in a mixture of propylene carbonate (PC) and dimethoxyethane in a ratio of 3:7. Enhanced performance was observed upon the substitution of conventional carbonates with fluorinated co-solvents. The findings suggest that LiDFOB is a thermostable salt, and its high conductivity contributes to the formation and stabilization of the interface of solid electrolytes. The results indicate that at low temperature conditions, a double salt should be used for lithium current sources, for example, 0.4 M LiDFOB and 0.6 M LiBF<sub>4</sub>, as well as electrolyte additives such as fluoroethylene carbonate and lithium nitrate. |
|---|---|
| ISSN: | 2673-3293 |