TY - JOUR
T1 - High-performance N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide/poly(vinylidene fluoride-hexafluoropropylene) gel polymer electrolytes for lithium metal batteries
AU - Pan, Xiaona
AU - Liu, Tianyi
AU - Kautz, David J.
AU - Mu, Linqin
AU - Tian, Chixia
AU - Long, Timothy E.
AU - Yang, Peixia
AU - Lin, Feng
N1 - Funding Information:
The work at Virginia Tech was supported by the Department of Chemistry Startup at Virginia Tech and ORAU Ralph E. Powe Junior Faculty Enhancement Award. X.P. and P.Y. gratefully acknowledge financial support from the Project of Natural Science Foundation of Heilongjiang Province of China (No. B2015004). X.P. acknowledges the support from China Scholarship Council. The authors also acknowledge the support from Stephen McCartney at the Nanoscale Characterization and Fabrication Laboratory at Virginia Tech. We thank Dr. Xu Feng and the Surface Analysis Laboratory at Virginia Tech for the XPS measurements.
Funding Information:
The work at Virginia Tech was supported by the Department of Chemistry Startup at Virginia Tech and ORAU Ralph E. Powe Junior Faculty Enhancement Award. X.P. and P.Y. gratefully acknowledge financial support from the Project of Natural Science Foundation of Heilongjiang Province of China (No. B2015004 ). X.P. acknowledges the support from China Scholarship Council . The authors also acknowledge the support from Stephen McCartney at the Nanoscale Characterization and Fabrication Laboratory at Virginia Tech . We thank Dr. Xu Feng and the Surface Analysis Laboratory at Virginia Tech for the XPS measurements.
Publisher Copyright:
© 2018 Elsevier B.V.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2018/11/1
Y1 - 2018/11/1
N2 - Ionically conductive polymer electrolytes represent a class of safe and environment-friendly electrolytes for next-generation alkali metal batteries. Understanding the interplay between composition-driven interfacial processes and battery performance can fundamentally inform the design of polymer electrolytes for practical applications. In this study, we fabricate lithium metal batteries based on transparent free-standing ionic liquid gel polymer electrolytes (ILGPEs) and LiFePO4 cathodes. We develop the ILGPEs using a composite of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (PP13TFSI), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). A thorough compositional optimization shows that the lithium ion conductivity of the ILGPE increases with the increase of PP13TFSI and LiTFSI, reaching maxima of 1.3 mS cm−1 at 23 °C and 5.82 mS cm−1 at 80 °C when the ILGPE contains 60 wt% PP13TFSI and 20 wt% LiTFSI. The optimized ILGPE exhibits excellent interfacial stability against the lithium metal, as signified by the stable interfacial resistance upon long-term storage. The LiFePO4|ILGPE|Li cells can deliver superior battery performance with a practical capacity approaching 89.5% of the theoretical capacity and capacity retention of 95.0% after 200 cycles. The formation of the electrode–electrolyte interphases takes place primarily during the initial cycles, which likely accounts for the activation period observed in LiFePO4|ILGPE|Li cells.
AB - Ionically conductive polymer electrolytes represent a class of safe and environment-friendly electrolytes for next-generation alkali metal batteries. Understanding the interplay between composition-driven interfacial processes and battery performance can fundamentally inform the design of polymer electrolytes for practical applications. In this study, we fabricate lithium metal batteries based on transparent free-standing ionic liquid gel polymer electrolytes (ILGPEs) and LiFePO4 cathodes. We develop the ILGPEs using a composite of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (PP13TFSI), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). A thorough compositional optimization shows that the lithium ion conductivity of the ILGPE increases with the increase of PP13TFSI and LiTFSI, reaching maxima of 1.3 mS cm−1 at 23 °C and 5.82 mS cm−1 at 80 °C when the ILGPE contains 60 wt% PP13TFSI and 20 wt% LiTFSI. The optimized ILGPE exhibits excellent interfacial stability against the lithium metal, as signified by the stable interfacial resistance upon long-term storage. The LiFePO4|ILGPE|Li cells can deliver superior battery performance with a practical capacity approaching 89.5% of the theoretical capacity and capacity retention of 95.0% after 200 cycles. The formation of the electrode–electrolyte interphases takes place primarily during the initial cycles, which likely accounts for the activation period observed in LiFePO4|ILGPE|Li cells.
KW - Freestanding
KW - Interfacial chemistry
KW - Ionic conductivity
KW - Ionic liquid gel polymer electrolyte
KW - Lithium metal battery
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U2 - 10.1016/j.jpowsour.2018.09.080
DO - 10.1016/j.jpowsour.2018.09.080
M3 - Article
AN - SCOPUS:85054281506
SN - 0378-7753
VL - 403
SP - 127
EP - 136
JO - Journal of Power Sources
JF - Journal of Power Sources
ER -