TY - JOUR
T1 - Moderate-concentration fluorinated electrolyte for high-energy-density Si//LiNi0.8Co0.1Mn0.1O2batteries
AU - Umesh, Bharath
AU - Chandra Rath, Purna
AU - Hernandha, Rahmandhika Firdauzha Hary
AU - Lin, Jeng Yu
AU - Majumder, Subhasish Basu
AU - Dong, Quan Feng
AU - Chang, Jeng Kuei
N1 - Publisher Copyright:
©
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/11/2
Y1 - 2020/11/2
N2 - Highly concentrated electrolytes, although promising, are of high cost and show high viscosity and unsatisfactory wettability toward electrodes and separators, making them unfavorable for practical applications. A more rational electrolyte design is thus needed. Here, we investigate moderately concentrated electrolytes and find that the lithium bis(fluorosulfonyl)imide (LiFSI) concentration effects on the capacity, rate capability, and cycling stability of Si anodes in an ethylene carbonate (EC)/diethyl carbonate (DEC) mixed electrolyte are opposite to those in a fluoroethylene carbonate (FEC) electrolyte. The reasons for these results are systematically examined using Raman spectroscopy, transmission electron microscopy, electrochemical impedance spectroscopy, and the galvanostatic intermittent titration technique. A detailed X-ray photoelectron spectroscopy analysis is performed to study the solid electrolyte interphase chemistry. Al corrosion that occurs with the EC/DEC-based electrolyte can be effectively suppressed with the FEC-based electrolyte if an adequate LiFSI concentration is used. In the proposed 2 mLiFSI/FEC electrolyte, the Si anode has reversible capacities of 2630 and 855 mA h g-1 at 0.2 and 5 A g-1, respectively, and ~75% capacity retention after 200 cycles (remarkably higher than that obtained with the EC/DEC-based electrolyte). This electrolyte also shows great compatibility with the high-energy-density LiNi0.8Co0.1Mn0.1O2 (NMC-811) cathode, allowing a stable charge-discharge of a Si//NMC-811 full cell.
AB - Highly concentrated electrolytes, although promising, are of high cost and show high viscosity and unsatisfactory wettability toward electrodes and separators, making them unfavorable for practical applications. A more rational electrolyte design is thus needed. Here, we investigate moderately concentrated electrolytes and find that the lithium bis(fluorosulfonyl)imide (LiFSI) concentration effects on the capacity, rate capability, and cycling stability of Si anodes in an ethylene carbonate (EC)/diethyl carbonate (DEC) mixed electrolyte are opposite to those in a fluoroethylene carbonate (FEC) electrolyte. The reasons for these results are systematically examined using Raman spectroscopy, transmission electron microscopy, electrochemical impedance spectroscopy, and the galvanostatic intermittent titration technique. A detailed X-ray photoelectron spectroscopy analysis is performed to study the solid electrolyte interphase chemistry. Al corrosion that occurs with the EC/DEC-based electrolyte can be effectively suppressed with the FEC-based electrolyte if an adequate LiFSI concentration is used. In the proposed 2 mLiFSI/FEC electrolyte, the Si anode has reversible capacities of 2630 and 855 mA h g-1 at 0.2 and 5 A g-1, respectively, and ~75% capacity retention after 200 cycles (remarkably higher than that obtained with the EC/DEC-based electrolyte). This electrolyte also shows great compatibility with the high-energy-density LiNi0.8Co0.1Mn0.1O2 (NMC-811) cathode, allowing a stable charge-discharge of a Si//NMC-811 full cell.
KW - Al corrosion
KW - Cycle life
KW - Electrolyte design
KW - Li salt concentration
KW - Silicon anode
KW - Solid electrolyte interphase
UR - http://www.scopus.com/inward/record.url?scp=85095871291&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.0c05560
DO - 10.1021/acssuschemeng.0c05560
M3 - Article
AN - SCOPUS:85095871291
SN - 2168-0485
VL - 8
SP - 16252
EP - 16261
JO - ACS Sustainable Chemistry and Engineering
JF - ACS Sustainable Chemistry and Engineering
IS - 43
ER -