Aqueous Zn-ion batteries have attracted much attention due to their unique high safety and low-cost merits.However,their practical applications are at a slow pace due to their short cycle life,which fundamentally resu...Aqueous Zn-ion batteries have attracted much attention due to their unique high safety and low-cost merits.However,their practical applications are at a slow pace due to their short cycle life,which fundamentally results from the instability of the positive/negative electrode interface in the traditional dilute aqueous electrolytes with high water activity.Developing highly concentrated electrolyte(HCE)has been considered as an effective solution.Unlike previous studies of single salt-based HCE(SSHCE),herein,a new dual-salt HCE(15 m ZnCl_(2)+10 m NH_(4)NH_(2)SO_(3)DS-HCE)was proposed for the first time.DS-HCE was proven to simultaneously possess higher conductivity than traditional dilute electrolytes and ultralow water activity of SS-HCE by the regulation of dual high-concentration salts on the solvation structure,which renders the Zn‖Zn symmetric cell the record-long cycling life of 2200 h compared with those with SS-HCE(30 m ZnCl_(2),300 h)and other reported HCEs.Additionally,the Zn‖NH_(4)V_(4)O_(10)full cell with DS-HCE demonstrated impressed rate capability within a wide-range current densities from 0.1 to 10 A g^(-1).Moreover,at the high current density of 5 A g^(-1),the full cell shows almost100%capacity retention after 4000 cycles,which indicates the promising future of the DS-HCE system for long-duration aqueous Zn-ion batteries.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.52171147)the Tenthousand Talents Program+2 种基金the K.C.Wong Pioneer Talent Programthe National Key R&D Program of China(2024YFE0101100)the Inner Mengolia Science and Technology Plan(No.2021ZD0033).
文摘Aqueous Zn-ion batteries have attracted much attention due to their unique high safety and low-cost merits.However,their practical applications are at a slow pace due to their short cycle life,which fundamentally results from the instability of the positive/negative electrode interface in the traditional dilute aqueous electrolytes with high water activity.Developing highly concentrated electrolyte(HCE)has been considered as an effective solution.Unlike previous studies of single salt-based HCE(SSHCE),herein,a new dual-salt HCE(15 m ZnCl_(2)+10 m NH_(4)NH_(2)SO_(3)DS-HCE)was proposed for the first time.DS-HCE was proven to simultaneously possess higher conductivity than traditional dilute electrolytes and ultralow water activity of SS-HCE by the regulation of dual high-concentration salts on the solvation structure,which renders the Zn‖Zn symmetric cell the record-long cycling life of 2200 h compared with those with SS-HCE(30 m ZnCl_(2),300 h)and other reported HCEs.Additionally,the Zn‖NH_(4)V_(4)O_(10)full cell with DS-HCE demonstrated impressed rate capability within a wide-range current densities from 0.1 to 10 A g^(-1).Moreover,at the high current density of 5 A g^(-1),the full cell shows almost100%capacity retention after 4000 cycles,which indicates the promising future of the DS-HCE system for long-duration aqueous Zn-ion batteries.
