Abstract
Layered Li- and Mn-rich (LMR) oxides are considered as major/foremost charge storage materials for Li-ion cells due to their remarkable charge storage capacities of ≥250 mAh g-1. Despite this, they face the challenges of capacity and discharge potential fading after extensive cycling, which may arise due to the conversion of layered material to spinel and the movement of transition metals to the alkali metal layer. Herewith, Fe-substituted LMR oxide materials Li1.2Ni0.13Mn0.54Co0.13-xO2 (x = 0.03, 0.05) and Li1.2Ni0.13Mn0.54-xCo0.13O2 (x = 0.05) are prepared by using the sol-gel synthesis and annealing at a temperature of 900 °C for 12 h. The charge storage performance of pristine Li1.2Ni0.13Mn0.54Co0.13O2 (LNMCO) and Fe-doped materials such as Li1.2Ni0.13Mn0.54Co0.10Fe0.03O2 (LNMCF0.03O), Li1.2Ni0.13Mn0.54Co0.08Fe0.05O2 (LNMCF0.05O) and Li1.2Ni0.13Mn0.49Fe0.05Co0.13O2 (LNMF0.05CO) has been investigated by galvanostatic charge-discharge cycling, where they possess charge storage capacities of around 264, 266, 235, and 255 mAh g-1, respectively, when cycled at 20 mA g-1 (C/10) with capacity retention values of 69.8, 68.3, 90.7, and 81.5% after completing 140 cycles at C/5 rate. Thus, the substitution of Co or Mn with Fe improves the electrochemical cycling stability. Among all these four samples, Fe-substituted material LNMF0.05CO demonstrates a superior rate capability compared to others. Interestingly, the fading of discharge voltage is found to be less in the case of Fe-substituted materials. These results demonstrate that LNMCF0.05O and LNMF0.05CO have better cycling stability, low voltage fade, and better rate capability than pristine LNMCO and LNMCF0.03O materials. In the full cell, the pristine LNMCO and LNMCF0.05O materials exhibit storage capacities of 266.2 and 230.0 mAh g-1, respectively, in the initial cycle at C/10 rate (1.8-4.7 V), and the capacity retention values are found to be around 76.2 and 90.9% after 200 cycles upon cycling at a C/2 rate, thus demonstrating the significant improvement in the electrochemical performance upon substitution of Co with Fe.
Original language | English |
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Pages (from-to) | 19266-19277 |
Number of pages | 12 |
Journal | Energy and Fuels |
Volume | 37 |
Issue number | 23 |
DOIs | |
State | Published - 7 Dec 2023 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2023 American Chemical Society.
Funding
The authors are grateful to the SRM Institute of Science and Technology, Kattankulathur, for the fellowship, the research facilities including SRM-SCIF and NRC for structural analysis, and the Energy Conversion and Storage Devices (ECSD) Laboratory for conducting the electrochemical measurements. The financial support from the Start-up Research Grant SRG/2022/001178 by SERB, India, is highly acknowledged.
Funders | Funder number |
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SRM Institute of Science and Technology, Kattankulathur | |
National Research Council Canada | SRG/2022/001178 |
Science and Engineering Research Board |