Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2...Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2-dioxathiolane-2,2-dioxide(DTD),with the structure of sulfur surrounded by four oxygen atoms,have been proposed but less knowledge is available on the relationship between their molecular structures and interfacial stability.This work compares two similar molecule structure of cyclic sulfurcontaining additives,DTD and ethylene sulfite(ES),to investigate their effects on the electrochemical performance of NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM)||hard carbon(HC)pouch cells.Therein,ES with the structure of sulfur surrounded by three oxygen atoms,as electrolyte additive,is investigated in the SIBs for the first time.It is shown that adding 3.0%ES or 2.0%DTD(the optimal proportion)in the Control electrolyte(1 M NaPF_(6)in EC:EMC=3:7 with 5.0%FEC in weight)can improve cyclic stability and rate performance,respectively.Even under the high-temperature conditions,both ES and DTD exhibit good performance,but DTD is superior.Combinations of electrochemical methods,multi-spectroscopy,and theoretical calculations have been employed to evaluate and compare the effects of ES and DTD on sodium-ion battery.They reveal that ES and DTD can generate different content and composition by redox reaction on cathode and anode surface.The more and effective high-valence sulfur-containing components for DTD are the main reason to explain the better effect on DTD.This work shares new insights into the relationship between cyclic sulfur-containing additive molecule structure and electrolyte-electrode interface films effect,which fills the blanks of previous research.展开更多
基金supported by the National Natural Science Foundation of China(21875076)the Guangdong Provincial International Joint Research Center for Energy Storage Materials(2023A0505090009)the Science and Technology Planning Project of Guangzhou City(2023B03J1278)。
文摘Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2-dioxathiolane-2,2-dioxide(DTD),with the structure of sulfur surrounded by four oxygen atoms,have been proposed but less knowledge is available on the relationship between their molecular structures and interfacial stability.This work compares two similar molecule structure of cyclic sulfurcontaining additives,DTD and ethylene sulfite(ES),to investigate their effects on the electrochemical performance of NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM)||hard carbon(HC)pouch cells.Therein,ES with the structure of sulfur surrounded by three oxygen atoms,as electrolyte additive,is investigated in the SIBs for the first time.It is shown that adding 3.0%ES or 2.0%DTD(the optimal proportion)in the Control electrolyte(1 M NaPF_(6)in EC:EMC=3:7 with 5.0%FEC in weight)can improve cyclic stability and rate performance,respectively.Even under the high-temperature conditions,both ES and DTD exhibit good performance,but DTD is superior.Combinations of electrochemical methods,multi-spectroscopy,and theoretical calculations have been employed to evaluate and compare the effects of ES and DTD on sodium-ion battery.They reveal that ES and DTD can generate different content and composition by redox reaction on cathode and anode surface.The more and effective high-valence sulfur-containing components for DTD are the main reason to explain the better effect on DTD.This work shares new insights into the relationship between cyclic sulfur-containing additive molecule structure and electrolyte-electrode interface films effect,which fills the blanks of previous research.
