Achieving long-cycling sodium-ion full cells in ether-based electrolyte with vinylene carbonate additive

Application of sodium-ion batteries is suppressed due to the lack of appropriate electrolytes matching cathode and anode simultaneously.Ether-based electrolytes,preference of anode materials,cannot match with high-potential cathodes failing to apply in full cells.Herein,vinylene carbonate(VC)as an additive into NaCF_(3) SO_(3)-Diglyme(DGM)could make sodium-ion full cells applicable without preactivation of cathode and anode.The assembled FeS@C||Na3 V2(PO_(4))_(3)@C full cell with this electrolyte exhibits long term cycling stability and high capacity retention.The deduced reason is additive VC,whose HOMO level value is close to that of DGM,not only change the solvent sheath structure of Na^(+),but also is synergistically oxidized with DGM to form integrity and consecutive cathode electrolyte interphase on Na3 V2(PO_(4))_(3)@C cathode,which could effectively improve the oxidative stability of electrolyte and prevent the electrolyte decomposition.This work displays a new way to optimize the sodium-ion full cell seasily with bright practical application potential.

Vinylene carbonate additive for EMITFSI-based electrolyte for Li/LiFePO_4 batteries

Ionic liquids have been paid much attention and are considered to replace the conventional organic electrolyte and solve the safety issues by virtue of nonvolatility,non-flammability,high ionic conductivity and extended electrochemical steady window.The paper introduces ionic liquids electrolyte on basis of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMITFSI),which shows a wide electrochemical window (0.5-4.5 V vs.Li+/Li),and is theoretically feasible as an electrolyte for Li/LiFePO4batteries to improve the safety.Linear sweep voltammetry (LSV) was performed to investigate the electrochemical stability window of the polymer electrolyte.Interfacial resistance for Li/electrolyte/Li symmetric cells and Li/electrolyte/LiFePO4 cells were studied by electrochemical impedance spectroscopy (EIS).The results showed that additive vinylene carbonate (VC) enhances the formation of solid electrolyte interphase film to protect lithium anodes from corrosion and improves the compatibility of ionic liquid electrolyte towards lithium anodes.Accordingly,Li/LiFePO4cells delivers the initial discharge capacity of 124 mAh g-1 at a current rate of 0.1C in the ionic liquid electrolyte (EMITFSI+0.8 mol L-1LiTFSI+5 wt%VC),and shows better cyclability than in the ionic liquid electrolyte without VC.

PROPERTIES AND SYNTHESIS OF NEW SUPPORTS FOR IMMOBILIZATION OF ENZYMES BY COPOLYMERIZATION OF VINYLENE CARBONATE AND METHACRYLIC ACID

Methacrylic acid first was neutralized with an aqueous solution of NaOH to pH = 6.0 similar to 7.0, vinylene carbonate (VCA) was added to the solution, then monomers were copolymerized in paraffin oil by means of reverse-phase suspension polymerization and hydrophilic copolymeric supports were prepared. The properties of the supports were determined using trypsin and results show that the amount of enzymes coupled to the supports and the specific activity of immobilized trypsin are related to the content of VCA structure units, reaction time and concentration of enzyme solution, etc.

INVESTIGATIONS ON VINYLENE CARBONATE Ⅰ. PREPARATION AND PROPERTIES OF POLY-(VINYLENEC ARBONATE)

Bulk polymerization of vinylene carbonate using t-butylperoxypivalate at 40℃gave colourless, high molecular weight poly(vinylene carbonate) (PVCA). Solutions of PVCA in acetone and DMF are not stable at 25℃and this degradation was studied. From measurements in DMF with unfractionated PVCA a Mark-Houwink equation was obtained:

Synthesis of aminoisoquinolines via Rh-catalyzed[4+2]annulation of benzamidamides with vinylene carbonate

A new strategy is developed for the synthesis of 1-aminoisoquinoline derivatives.This Rh(III)-catalyzed[4+2]annulation reaction employs benzamidines as efficient directing groups and the vinylene carbonate as an acetylene surrogate.Additionally,the reaction features broad substrate scopes and good yields,only producing carbonate anion as byproduct.

Application of Film-forming Additives for Ionic Liquid Based Electrolyte

N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide was synthesized for the application in ionic liquid based electrolytes in lithium ion battery, 10% vinylene carbonate (VC) and 10% 1,3-propane sultone (PS) were added to the electrolyte system respectively as additives to improve the property of solid electrolyte interface and cyclic performance. The results of cyclic voltammetry showed that homogenous and compact solid electrolyte interface film formed on graphite electrode which was detected by observing the morphology of cycled graphite anode. Charging and discharging performance of LiFePO4/Li half cell was tested in the electrolyte with or without additives. The initial specific discharging capacities were increased to 129.4 and 123.0 mA·h/g by the addition of VC and PS, respectively, compared with that of additive-free electrolyte. The discharging retentions were 88.9% and 84.6% in electrolyte containing VC and PS after 10 cycles.