Chaotropic anion based “water-in-salt” electrolyte realizes a high voltage Zn–graphite dual-ion battery

Abstract

Aqueous Zn-based batteries are promising candidates for grid energy storage due to their low cost, intrinsic safety, and environmental friendliness. Nevertheless, they suffer from limited energy density due to the...

Toward High Energy Density Aqueous Zinc‐Ion Batteries: Recent Progress and Future Perspectives

“…[27][28][29] Table 1 shows the reported electrolyte designs to improve the narrow ESW of aqueous electrolytes. [30][31][32][33][34][35][36][37][38][39][40][41] Herein, we discuss strategies to suppress water decomposition for the broad ESW of aqueous electrolytes and high operating voltage in ZIBs, including the optimization of pH, utilization of bication electrolytes, introduction of small-dipole additives, and design of polymer-supported gel electrolytes.…”

“…For instance, Zafar et al developed a high-voltage aqueous Zn j graphite DIB based on an 8 m Zn(ClO 4 ) 2 WIS electrolyte. [37] They manipulated graphite as a cathode material and con- ducted cyclic voltammetry to determine the working potential (Figure 5b). The fabricated cell exhibited an oxidation peak (I pa ) at 2.4 V representing the ClO 4…”

“…Table 2 summarizes the as-reported strategies to develop high voltage working cathode materials. [16,18,31,37,58,61,66,[68][69][70][71][72][73][74][75][76] As illustrated in the table, not only intercalating materials, adopting halogen molecules and p-type organic polymers also can provide high working voltage. It should be further CV at different scan rates from 0.1 to 0.9 mV s À 1 .…”

“…These side reactions induce critical problems in achieving high‐performance ZIBs with high‐voltage and long cycle life because they consume electrolytes and increase internal resistance [27–29] . Table 1 shows the reported electrolyte designs to improve the narrow ESW of aqueous electrolytes [30–41] . Herein, we discuss strategies to suppress water decomposition for the broad ESW of aqueous electrolytes and high operating voltage in ZIBs, including the optimization of pH, utilization of bication electrolytes, introduction of small‐dipole additives, and design of polymer‐supported gel electrolytes.…”

Suppression of H2 bubble formation on an electrified Pt electrode interface in an acidic “water-in-salt” electrolyte solution

“…Therefore, electrochemical (de)lithiation of conventional active materials for both the anode and cathode of lithium ion batteries are allowed in WiSE, and the corresponding electrochemical potentials are beyond the limit of typical aqueous electrolyte solutions. [17][18][19][20][21][22][23][24][25][26][27][28][29][30] In addition to the interesting physicochemical characteristics of a bulk WiSE, an interfacial layer (IFL) on an electrode in WiSE was revealed to be distinctive compared to interfaces observed in conventional aqueous solutions with relatively low electrolyte concentrations (i.e., "salt-in-water" electrolyte solution). [31][32][33] Borodin et al reported that IFLs are strongly related to an applied electrode potential, referring to the point of zero charges (PZC) of an electrode.…”