Lithium metal batteries (LMBs) with nickel-rich cathodes are promising candidates for next-generation, high-energy batteries. However, the highly reactive electrodes usually exhibit poor interfacial compatibility with conventional electrolytes, leading to limited cyclability. Herein, a locally concentrated ionic liquid electrolyte (LCILE) consisting of lithium bis(fluorosulfonyl)imide (LiFSI), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EmimFSI), and 1,2-difluorobenzene (dFBn) is designed to overcome this challenge. As a cosolvent, dFBn not only promotes the Li+ transport with respect to the electrolyte based on the ionic liquid only, but also has beneficial effects on the electrode/electrolyte interphases (EEIs) on lithium metal anodes (LMAs) and LiNi0.8Mn0.1Co0.1O2 (NMC811) cathodes. As a result, the developed LCILE enables dendrite-free cycling of LMAs with a coulombic efficiency (CE) up to 99.57% at 0.5 mA cm−2 and highly stable cycling of Li/NMC811 cells (4.4 V) at C/3 charge and 1 C discharge (1 C = 2 mA cm−2) for 500 cycles with a capacity retention of 93%. In contrast, the dFBn-free electrolyte achieves lithium stripping/plating CE, and the Li/NMC811 cells’ capacity retention of only 98.22% and 16%, respectively under the same conditions. The insight into the coordination structure, promoted Li+ transport, and EEI characteristics gives fundamental information essential for further developing (IL-based) electrolytes for long-life, high-energy LMBs.

Difluorobenzene-based locally concentrated ionic liquid electrolyte enabling stable cycling of lithium metal batteries with nickel-rich cathode / Liu, Xu; Mariani, Alessandro; Diemant, Thomas; Di Pietro, Maria Enrica; Dong, Xu; Kuenzel, Matthias; Mele, Andrea; Passerini, Stefano. - In: ADVANCED ENERGY MATERIALS. - ISSN 1614-6832. - 12:25(2022). [10.1002/aenm.202200862]

Difluorobenzene-based locally concentrated ionic liquid electrolyte enabling stable cycling of lithium metal batteries with nickel-rich cathode

Passerini, Stefano
2022

Abstract

Lithium metal batteries (LMBs) with nickel-rich cathodes are promising candidates for next-generation, high-energy batteries. However, the highly reactive electrodes usually exhibit poor interfacial compatibility with conventional electrolytes, leading to limited cyclability. Herein, a locally concentrated ionic liquid electrolyte (LCILE) consisting of lithium bis(fluorosulfonyl)imide (LiFSI), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EmimFSI), and 1,2-difluorobenzene (dFBn) is designed to overcome this challenge. As a cosolvent, dFBn not only promotes the Li+ transport with respect to the electrolyte based on the ionic liquid only, but also has beneficial effects on the electrode/electrolyte interphases (EEIs) on lithium metal anodes (LMAs) and LiNi0.8Mn0.1Co0.1O2 (NMC811) cathodes. As a result, the developed LCILE enables dendrite-free cycling of LMAs with a coulombic efficiency (CE) up to 99.57% at 0.5 mA cm−2 and highly stable cycling of Li/NMC811 cells (4.4 V) at C/3 charge and 1 C discharge (1 C = 2 mA cm−2) for 500 cycles with a capacity retention of 93%. In contrast, the dFBn-free electrolyte achieves lithium stripping/plating CE, and the Li/NMC811 cells’ capacity retention of only 98.22% and 16%, respectively under the same conditions. The insight into the coordination structure, promoted Li+ transport, and EEI characteristics gives fundamental information essential for further developing (IL-based) electrolytes for long-life, high-energy LMBs.
2022
1,2-difluorobenzene; ionic liquids; lithium metal batteries; locally concentrated electrolytes; nickel-rich cathodes
01 Pubblicazione su rivista::01a Articolo in rivista
Difluorobenzene-based locally concentrated ionic liquid electrolyte enabling stable cycling of lithium metal batteries with nickel-rich cathode / Liu, Xu; Mariani, Alessandro; Diemant, Thomas; Di Pietro, Maria Enrica; Dong, Xu; Kuenzel, Matthias; Mele, Andrea; Passerini, Stefano. - In: ADVANCED ENERGY MATERIALS. - ISSN 1614-6832. - 12:25(2022). [10.1002/aenm.202200862]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1676952
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