Ionic liquid electrolyte for lithium metal batteries : physical, electrochemical, and interfacial studies of N-Methyl-N-butylmorpholinium Bis(fluorosulfonyl)imide
Data(s) |
01/01/2010
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Resumo |
The ionic liquid (IL) <i>N</i>-methyl-<i>N</i>-butylmorpholinium bis(fluorosulfonyl)imide (C<sub>4</sub>mmor FSI) is examined from physical and electrochemical perspectives. Pulsed field gradient NMR spectroscopy shows that ion diffusivities are low compared with similar, non-ethereal ILs. Ionicity values indicate that above room temperature, less than 50% of ions contribute to conductivity.<br /><br />Lithium cycling in symmetrical cells using a C<sub>4</sub>mmor FSI-based electrolyte is best demonstrated at elevated temperatures. Specific capacities of 130 mAh g<sup>−1</sup> are achieved in a Li−LiFePO<sub>4</sub> battery at 85 °C. FT-IR spectroscopic investigations of lithium electrodes suggest the presence of alkoxide species in the solid electrolyte interphase (SEI), implying a ring-opening reaction of C<sub>4</sub>mmor with lithium metal. In contrast, the SEI derived from <i>N</i>-methyl-<i>N</i>-propylpiperidinium FSI lacks the alkoxide signature but shows signs of alkyl unsaturation, and the activation energy for Li+ transport through this SEI is slightly lower than that for the C<sub>4</sub>mmor-derived SEI. Our detailed findings give insight into the capabilities and limitations of rechargeable lithium metal batteries utilizing a C<sub>4</sub>mmor FSI electrolyte.<br /> |
Identificador | |
Idioma(s) |
eng |
Publicador |
American Chemical Society |
Relação |
http://dro.deakin.edu.au/eserv/DU:30039934/bayley-ionicliquid-2010.pdf http://dx.doi.org/10.1021/jp1054809 |
Direitos |
2010 American Chemical Society |
Tipo |
Journal Article |