Abstract
The polysulfide shuttle mechanism and insulating characteristics of sulfur and discharge products are the two major drawbacks of Li−S batteries. These increase internal cell resistances, resulting in low battery performance and life. In this study, we investigate the effect of cathode material on the cell resistances by preparing two different cathodes: by encapsulating sulfur (S) with pure Ketjen black (KBS) and with atomic vanadium and cobalt‐modified Ketjen black (VCKBS). In addition to the cathode material, the influence of crucial cell design parameters, namely electrolyte‐to‐sulfur (E/S) ratio and sulfur loading, on the cell resistances and battery performance is also compared. Electrochemical impedance spectroscopy (EIS) is applied to determine the individual cell resistances, whereas a system‐level performance model is used to estimate the system‐level specific energies and energy densities. The comparison of the cathodes shows that VCKBS significantly improves both cell‐ and system‐level performances, which are attributed to a significant decrease in cell resistances. The cells with higher sulfur loadings and lower E/S ratios show poorer performance for both cathodes. On the other hand, an E/S ratio of 6 mg L−1 can result in high cell‐ and system‐level performances for the VCKBS cathode.
Original language | English |
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Article number | e202300781 |
Journal | ChemElectroChem |
Early online date | 28 Feb 2024 |
DOIs | |
Publication status | E-pub ahead of print - 28 Feb 2024 |
Bibliographical note
Research FundingTurkiye Scholarship/Research Fellowship Program. Grant Number: 21PK070917
Prime Ministry of Turkey Presidency for Turks Abroad and Related Communities
Istanbul Development Agency. Grant Number: TR10/21/YEP/0001
Keywords
- Ketjen black
- Electrolyte-to-sulfur ratio
- Sulfur loading
- System-level performance
- Li−S batteries