A long-life aqueous Zn battery enabled by simultaneous suppressing cathode dissolution and Zn dendrites via a novel water-in-deep eutectic solvent electrolyte

Low-Cost and Large-Scale Preparation of H2O and Mg2+ Co-Preintercalated Vanadium Oxide with High-Performance Aqueous Zn-Ion Batteries

“…44 Such phenomenon was investigated by Zhang's work, which is mainly due to the fact that V 2 O 5 ultimately develops into a porous structure during initial charge and discharge processes, which will increase the specific surface area and offer more electrochemically active sites for Zn 2+ ion storage. 24 Furthermore, V 2 O 5 has poor cycling stability due to structural instability and chemical dissolution and thus often displays significant capacity fading upon long-term cycling. Significantly, the coinsertion of magnesium ions and water molecules has changed this situation.…”

“…That is, the nanosheets ultimately develop into a porous structure during initial charge and discharge processes, which will increase the specific surface area and offer more electrochemically active sites for Zn 2+ ion storage . Such phenomenon was investigated by Zhang’s work, which is mainly due to the fact that V 2 O 5 ultimately develops into a porous structure during initial charge and discharge processes, which will increase the specific surface area and offer more electrochemically active sites for Zn 2+ ion storage . Furthermore, V 2 O 5 has poor cycling stability due to structural instability and chemical dissolution and thus often displays significant capacity fading upon long-term cycling.…”

“…Later in Zhang’s work, the V 2 O 5 cathode shows an excellent cycle performance (91.1% capacity retention after 4000 cycles), which is ascribed to the insertion of zinc ions and water molecules because of charge-shielding effects . Moreover, ions such as Fe 2+ , Co 2+ , Ni 2+ , Mn 2+ , Zn 2+ , Cu 2+ , N­(CH 3 ) 4 + , and NH 4 + pre-intercalated in layered V 2 O 5 are also revealed to improve the electrochemical property through enhanced electrical conductivity, enlarged interlayer spacing, and excellent structural reversibility. ,, Interlayer spacing of V 2 O 5 increases with the increase of the hydrated ion radius. Hydrated Mg 2+ has an ion radius of 4.28 Å, which is larger than that of other hydrated ions, such as Li + (3.82 Å), Na + (3.58 Å), K + (3.31 Å), and Ca 2+ (4.12 Å).…”

“…Vanadium-based oxides have been widely investigated as cathodes in aqueous ZIBs due to a large layered V–O framework and rich redox states, which guaranteed facile ion movement and sufficient ion storage spaces. − To realize their practical application, capacity, cycle, and cost performance are the main issues to be considered. V 2 O 5 has a high theoretical capacity of 588 mAh g –1 but collapses and dissolves during charge and discharge, which leads to capacity fading during cycles.…”

Electrolyte Engineering via Competitive Solvation Structures for Developing Longevous Zinc Ion Batteries

“…As a continuation, electrolyte engineering, [34][35][36] a rising star, takes center stage in ZIBs, including (localized) highconcentration electrolytes, [37,38] weakly solvating electrolytes, [39] and deep eutectic electrolytes. [40,41] These functional electrolytes that alter the Zn 2+ solvation structure aim to decrease the free water solvent content, which could inhibit HER to a certain extent. Moreover, the anion or organic solvent coordinated Zn 2+ enables the formation of an efficient SEI to prohibit contact between water molecules and active Zn surface.…”