electrolyte
; lithium ion
; sulfur
; aqueous solution
; Article
; chemical reaction kinetics
; controlled study
; current density
; cyclic potentiometry
; electric battery
; electric potential
; electrochemical analysis
; energy
; lithiation
; oxidation reduction reaction
; phase separation
; priority journal
; Raman spectrometry
; reaction analysis
; thermodynamics
英文摘要:
Leveraging the most recent success in expanding the electrochemical stability window of aqueous electrolytes, in this work we create a unique Li-ion/sulfur chemistry of both high energy density and safety. We show that in the superconcentrated aqueous electrolyte, lithiation of sulfur experiences phase change from a highorder polysulfide to low-order polysulfides through solid-liquid two-phase reaction pathway, where the liquid polysulfide phase in the sulfide electrode is thermodynamically phase-separated from the superconcentrated aqueous electrolyte. The sulfurwith solid-liquid two-phase exhibits a reversible capacity of 1,327 mAh/(g of S), along with fast reaction kinetics and negligible polysulfide dissolution. By coupling a sulfur anode with different Li-ion cathode materials, the aqueous Li-ion/sulfur full cell delivers record-high energy densities up to 200 Wh/(kg of total electrode mass) for >1,000 cycles at ∼100% coulombic efficiency. These performances already approach that of commercial lithium-ion batteries (LIBs) using a nonaqueous electrolyte, along with intrinsic safety not possessed by the latter. The excellent performance of this aqueous battery chemistry significantly promotes the practical possibility of aqueous LIBs in large-format applications.
Yang, C., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Suo, L., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Borodin, O., US Army Research Laboratory, Power and Energy Division, Sensor and Electron Devices Electrochemistry Branch, Adelphi, MD 20783, United States; Wang, F., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Sun, W., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Gao, T., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Fan, X., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Hou, S., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Ma, Z., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States; Amine, K., Argonne National Laboratory, Chemical Sciences and Engineering Division, Argonne, IL 60439, United States; Xu, K., US Army Research Laboratory, Power and Energy Division, Sensor and Electron Devices Electrochemistry Branch, Adelphi, MD 20783, United States; Wang, C., Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20740, United States
Recommended Citation:
Yang C.,Suo L.,Borodin O.,et al. Unique aqueous Li-ion/sulfur chemistry with high energy density and reversibility[J]. Proceedings of the National Academy of Sciences of the United States of America,2017-01-01,114(24)