Improved solid electrolyte interphase and Li-storage performance of Si/graphite anode with ethylene sulfate as electrolyte additive

Abstract

Silicon/graphite composite anodes have drawn extensive attention in the field of power Li-ion batteries for application in electric vehicles because of their much higher capacity than that of traditional graphite anodes. In this work, ethylene sulfate (1,3,2-dioxathiolane-2,2-dioxide, DTD) is investigated as an electrolyte additive to improve the Li-storage performance of silicon/graphite composite anode. The electrochemical behavior of silicon/graphite anode including cyclic voltammogram, discharge/charge performance at various current density and during long-term cycling, and electrochemical impedance is systematically studied by adding different amounts of DTD into electrolyte. The effects of DTD on the solid/electrolyte interphase (SEI) film are analyzed through scanning electron microscopy, X-ray photoelectron and Fourier transform infrared spectroscopy. It is found that DTD participates into the film-formation process through its reductive decomposition reactions on electrode surface, producing a thin, uniform and stable SEI. The Li-storage performance of silicon/graphite anode is improved at an optimized addition amount of DTD.

Sulfur‐containing compounds as electrolyte additives for lithium‐ion batteries

“…Interestingly, in addition to graphite negative electrode, DTD endows high compatibility toward silicon oxide (SiO x )-based negative electrode. 110,111 Zheng et al 110 reported that the DTD-containing electrolyte, that is, 1.0 M LiPF 6 -EC/EMC/DMC/fluoroethylene carbonate (FEC) (1/1/1/0.1, by vol) + 3 wt% DTD, shows higher initial Coulombic efficiency of 83.7% from 79.4% (the control group) and high cycling performance (the LijjSiO x cells exhibits good cycle stability after 500 cycles with 80% capacity retention). Li et al 111 demonstrated that the addition of 1.5 wt% DTD in a well-formulated baseline electrolyte (i.e., 1.0 M LiPF 6 -EC/EMC/DEC [3:5:2, by wt] + 0.5 wt% lithium difluoro(oxalato)borate [LiDFOB] + 2 wt% LiFSI + 2 wt% FEC + 1 wt% PS) results in a clear improvement in the cyclability of SiO xbased compositejjLiNi 0.8 Mn 0.1 Co 0.1 O 2 pouch cell (e.g., ca.…”

Optimized Cycle and Safety Performance of Lithium–Metal Batteries with the Sustained‐Release Effect of Nano CaCO3

“…and higher viscosity, leading to electrolyte deterioration and gas production (Figure 1a). [24,25] To conquer the above issues, several LiNO 3containing additives have been successfully developed recently inspired by the sustained-release strategy, and their impressive performances demonstrate the great application potential of this method. [26,27] Therefore, optimizing the overall performance and cost of additives designed based on this strategy is of great research significance.Herein, we adopt cheap, environment-friendly CaCO 3 nanoparticles (40-80 nm) as a novel solid additive for LMBs.…”

Interfacing Si‐Based Electrodes: Impact of Liquid Electrolyte and Its Components

“…For the sake of completeness, reports where FEC is utilized as an electrolyte additive can be found in references [ 45–47,51–55,60–62,67,69,73,75–77,92–125 ] and reports utilizing VC as electrolyte additive can be found in references. [ 40,45,47–49,69,71,73,75–77,98,99,102–104,106,115,119,122,123,126–132 ]…”

“…XPS analysis suggested the formation of a thinner SEI containing sulfate and sulfonate species. [ 93 ] An et al. studied a number of different additives in high capacity NMC811||SiO x cells.…”

“…XPS analysis suggested the formation of a thinner SEI containing sulfate and sulfonate species. [93] An et al studied a number of different additives in high capacity NMC811||SiO x cells. The baseline electrolyte used was a conventional LiPF 6 /organic carbonatebased electrolyte that already contained several additives.…”