Nanostructures of solid electrolyte interphases and their consequences for microsized Sn anodes in sodium ion batteries

Abstract

An optimized solid electrolyte interphase is the key to stabilization of microparticle anodes.

Ionic‐Conducting and Robust Multilayered Solid Electrolyte Interphases for Greatly Improved Rate and Cycling Capabilities of Sodium Ion Full Cells

“…The polyether with abundant CO bonds was reported to exhibit high ion conductivity like the poly(ethylene oxide) electrolyte for high rate batteries. [ 15,43 ] Considering the inorganic component, such as NaF and Na 2 CO 3 , usually possess low ionic conductivity as 10 −21 –10 −31 S cm −1 . The increased sodium‐ion storage kinetics could be attributed the highly ionic conductive polyether‐like component in DME‐derived SEI, as verified by the discussion of electrochemical impedance spectroscopy (EIS) and GITT (Figures 3e,f and 4d).…”

“…The similar behavior was also found in Sn‐ or Fe‐based anode, which was involved in the formation of the SEI. [ 15,51 ] The chemical bonding of Bi with ether‐based electrolyte might be attributed to the high activity of intermediates produced during the decomposition of DME, which has a less steric hindrance compared to that derived from DEC as described in Equations [S11]–[S13], Supporting Information. The X‐ray diffraction (XRD) patterns of the Bi/C anode after 10 cycles in the DME‐ and EC/DEC‐based electrolyte (Figure S17, Supporting Information) show that all the peaks were assigned to the hexagonal Bi phase (PDF#44–1246) and no other peaks appeared in the two electrolytes.…”

“…Moreover, the enhanced electrochemical performance was also proven to be effective even in the alloying‐type anode with large volume expansion. [ 13–21 ] The enhanced performance of bulk bismuth in an ether‐based electrolyte was first reported by Chen’s group; [ 19 ] the microsized bulk bismuth could be incorporated into a porous architecture during the cycling, which ensures continuous sodium‐ion transport and structural stability for over 2000 cycles. Motivated by an intriguing phenomenon where the SEI itself was associated with the cyclic stability, the sodium storage performances could be further enhanced by matching ether‐based electrolytes with bismuth‐based composite materials, such as Bi@C, [ 22 ] Bi/N‐C, [ 23 ] Bi/graphite, [ 24 ] and Bi/graphene.…”

A Robust Solid Electrolyte Interphase Layer Augments the Ion Storage Capacity of Bimetallic‐Sulfide‐Containing Potassium‐Ion Batteries

“…[40] On the contrary,t he force responses in other electrolytes include an elastic region, regions of slope change induced by plastic or hardening processes,a nd regions of decreased force-possibly because of fracture and tip sliding. [40] Irreversible plastic deformation damages surface morphology,w hile elastic deformation contributes to relieving strain and maintaining integrity during the potassiationdepotassiation process.T hese results show that the NCS@RGO-2 electrode in the KFSI-EP electrolyte can form at hinner and more robust SEI layer. Thee xcellent mechan-ical properties of the SEI layer facilitate the contact between electrode and electrolyte,w hich endows the electrode with extra stability against volume expansion.…”

“…Forschungsartikel smoother than those obtained using other electrolytes, indicating that KFSI-EP is helpful for formation of thinner SEI layers on the surface of electrodes and exhibits fewer side reactions than other electrolytes.T he corresponding forcedisplacement curves and their detailed analyses were obtained by AFM and are presented in Figure 5i-p.T he force responses in KFSI-EP electrolyte include an elastic region and aregion of slope change induced by the response from the electrode. [40] On the contrary,t he force responses in other electrolytes include an elastic region, regions of slope change induced by plastic or hardening processes,a nd regions of decreased force-possibly because of fracture and tip sliding. [40] Irreversible plastic deformation damages surface morphology,w hile elastic deformation contributes to relieving strain and maintaining integrity during the potassiationdepotassiation process.T hese results show that the NCS@RGO-2 electrode in the KFSI-EP electrolyte can form at hinner and more robust SEI layer.…”