Ni-ion aqueous batteries(NIBs)were considered an important development direction for aqueous batteries due to the high theoretical capacity(913 mA h g^(-1))and volume capacity(8136 mA h cm^(-3))of nickel metal.Herein,...Ni-ion aqueous batteries(NIBs)were considered an important development direction for aqueous batteries due to the high theoretical capacity(913 mA h g^(-1))and volume capacity(8136 mA h cm^(-3))of nickel metal.Herein,an electrolyte additive(dodecyl trimethyl ammonium chloride,DTAC)was used to improve the electrolyte environment,achieve efficient transport of Ni-ion,and combine the intercalated vanadium oxide cathodes to realize novel strategy NIBs.Firstly,the introduction of trace amounts of DTAC improved the high-concentration NiCl_(2)(4.2 M)electrolyte environment and reconstructed the hydrogen bond network.Molecular dynamics(MD)calculations and electrochemical results indicated that DTAC contributed to the desolvation process of Ni^(2+)and the realization of fast dynamics.The results of Ni symmetric cells demonstrated that DTAC enhanced the rapid migration of Ni-ion and achieved longer cycling stability(1750/1500 h at 0.2/0.5 mA cm^(-2)without obvious short circuits).Secondly,the insertion of organic small molecules(pyrrolidine)into vanadium oxide(V_(2)O_(5))to expand the interlayer spacing promoted the Ni-ion storage capacity of the cathodes.The capacity retention rate of Ni full battery after 6000 cycles at 5 A g^(-1)reached 82.17%.This work provided a novel strategy for the development of Ni-ion aqueous batteries.展开更多
基金financially supported by the National Natural Science Foundation of China(NSFC)(22171030 and 21771028)。
文摘Ni-ion aqueous batteries(NIBs)were considered an important development direction for aqueous batteries due to the high theoretical capacity(913 mA h g^(-1))and volume capacity(8136 mA h cm^(-3))of nickel metal.Herein,an electrolyte additive(dodecyl trimethyl ammonium chloride,DTAC)was used to improve the electrolyte environment,achieve efficient transport of Ni-ion,and combine the intercalated vanadium oxide cathodes to realize novel strategy NIBs.Firstly,the introduction of trace amounts of DTAC improved the high-concentration NiCl_(2)(4.2 M)electrolyte environment and reconstructed the hydrogen bond network.Molecular dynamics(MD)calculations and electrochemical results indicated that DTAC contributed to the desolvation process of Ni^(2+)and the realization of fast dynamics.The results of Ni symmetric cells demonstrated that DTAC enhanced the rapid migration of Ni-ion and achieved longer cycling stability(1750/1500 h at 0.2/0.5 mA cm^(-2)without obvious short circuits).Secondly,the insertion of organic small molecules(pyrrolidine)into vanadium oxide(V_(2)O_(5))to expand the interlayer spacing promoted the Ni-ion storage capacity of the cathodes.The capacity retention rate of Ni full battery after 6000 cycles at 5 A g^(-1)reached 82.17%.This work provided a novel strategy for the development of Ni-ion aqueous batteries.