L ibo B2PC /DEC L ipf 6. , Land (0. 1C, 0. 5C), . (L ibob ) L ibob. , L ibob. . L ibob, 0. 5 mol L - 1., ARG, PC (

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1 ELECTROCHEM ISTRY Vol. 12 No. 3 Aug : (2006) L ibo B2PC /DEC, (, ),, 3 : L ibob, PC /DEC. L ibob2pc / DEC L i/arg, 0. 5 mol L 21 L ibob2pc /DEC (3 7). /,, SE I. : ; ; L ibob; PC; DEC : TM912 : A,. L ipf 6 2EC L ipf 6, HF,. (L ibob ) L ipf 6 [ 123 ], 60 [ 425 ]. ( PC) EC L ibob ( L ipf 6 [ 629 ] ),. L ibob, PC /DEC, (L ibob 2PC /DEC), L i/ ARG,. 1 [ 3 ] L ibob. ( RH < ) L i2 BOB, PC ( PC + DEC) ( PC DEC = ), ( 20 ). ARG, L i, L ibob, Land (0. 1C, 0. 5C), L ibob PC ( PC + DEC)., L ibob PC /DEC (3 7) 0. 7 mol L - 1, 0. 5 mol L - 1.,, L ibob,,.,. L ibob,,, PC ( Pa s),. DEC : , : , Tel: (86210) , E2mail: lifsh_ustb@163. com ( )

2 (20 ) Fig. 1 The effect of the L ithium salt concentration on electrolyte conductivities in different solvent system s at room temperature (20 ) mol L - 1 L ibob - PC L i/arg Fig. 2 Initial charging - discharging curve of the L i/ ARG cell with 0. 7 mol L - 1 L ibob2pc electrolyte, L i/arg 2, L ibob 2PC L i/ ARG., 1. 6 V 0. 7 V, L ibob ( SE I ), PC,. 1, 5 L ibob, L i/arg,. 1., 0. 5 mol L - 1 L ibob2pc /DEC (3 7),, mah g - 1, %, 79%. (21% ) SE I. 1, 0. 7 mol L - 1 L ibob 2PC /DEC ( 1 1) 0. 5 mol L - 1 L ibob 2PC /DEC (3 7),.,,., 0. 5 mol L - 1 L ibob 2PC /DEC (3 7) L i/arg. 3,,, 280 mah g - 1, 1 L i/arg Tab. 1 Initial charge2discharge capacity of the lithium2ion battery using different electrolytes Electrolytes Initial discharge capacity/mah g - 1 Initial charge capacity /mah g - 1 Irreversible capacity /mah g - 1 Cycle efficiency /% 0. 7mol L - 1 L ibob2pc mol L - 1 L ibob2pc /DEC (3 2) mol L - 1 L ibob2pc /DEC (1 1) mol L - 1 L ibob2pc /DEC (2 3) mol L - 1 L ibob2pc /DEC (3 7)

3 3 : L ibob2pc /DEC L i/arg Fig. 3 The cycling performance of L i/arg cell using different electrolytes 79%, 98% mol L - 1 L ibob2pc /DEC (3 7) L i/arg 0. 5C 0. 1C., 0. 5C, 50 mah g - 1, 0. 5 mol L - 1 L ibob 2PC /DEC (3 7),, mol L - 1 L ibob2pc /DEC (3 7) mol L - 1 L ibob 2PC /DEC (3 7) L i/arg.,,,,., mol L - 1 L ibob2pc /DEC ( 3 7) L i/arg Fig. 4 Comparision of capacity p roperty of the L i/arg cell with 0. 5 mol L - 1 L ibob2pc /DEC (3 7) electrolyte at different rate mol L - 1 L ibob2pc /DEC (3 7) L i/ ARG Fig. 5 A. C. impedance of the L i/arg cell using 0. 5 mol L - 1 L ibob - PC /DEC (3 7) electrolyte with different cyclic number

4 , ( 0. 5C).,,, SE I, mol L - 1 L ibob 2PC / DEC (3 7),, 1, 1. 7 V, SE I,, mol L - 1 L ibob2pc /DEC ( 3 7 ) ARG (0. 05 mv / s) Fig. 6 CV curves of the ARG anode in 0. 5 mol L - 1 L i2 BOB - PC /DEC (3 7) electrolyte scan rate = mv / s 3 L ibob2pc /DEC L i/arg, 0. 5 mol L - 1 L i2 BOB2PC /DEC (3 7) mah g - 1, 79%, 98%., 1. 7 V, SE I. SE I. (R efe rence s) : [ 1 ] Xu K, Zhang S S, Poese B A, et al. L ithium bis(oxala2 to) borate stablize graphite anode in p ropylene carbonate [ J ]. Electrochemcal and Solid2state letters, 2002, 5 (11) : A [ 2 ] L ischka U, W ietelmann U, W egner M. L ithium bisox2 alatoborate, the p roduction thereof and its use as a con2 ducting salt[ P ]. German. Patten: DE C1, [ 3 ] Xu K, Zhang S S, Jow T R, et al. L ibob as salt for lithium 2ion batteries[ J ]. Electrochemcal and Solid2state Letters, 2002, 5 (1) : A26 A29. [ 4 ] Xu K, Zhang S S, Jow T R. Electrochem ical impedance study of graphite / electrolyte interface formed in L ibob / PC electrolyte [ J ]. Journal of Power Source, 2005, 143: [ 5 ] Yu B itao ( ), L i Fushen ( ), Q iu W eihua ( ), et al. The development of lithium salts for L i2ion battery electrolytes [ J ]. Battery ( in Chinese), 2004, 34 (6) : [ 6 ] Krause L J, Lamanna W, Summerfield J, et al. Corro2 sion of alum inum at high voltages in non2aqueous elec2 trolytes containing perfluoroalkysufonyl inides; new lith2 ium salts for lithium 2ion cells [ J ]. J. Power Sources, 1997, 68: 320. [ 7 ] Ohta A, Koshuna H, Okuno H, et al. Relationship be2 tween carbonaceous materials and electrolyte in seconda2 ry lithium 2ion batteries [ J ]. J. Power Sources, 1995, 54: 6. [ 8 ] Zhuang Quanchao ( ), W u Shan ( ), L iu W enshan ( ), et al. The research of organic elec2 trolyte solutions for L i2ion batteries[ J ]. Electrochem is2 try ( in Chinese), 2001, 7 (4) : [ 9 ] Xu W, Angell C A. L ibob and its derivatives, weakly coordinating anions, and the excep tional conductivity of their nonaqueous solutions [ J ]. Electrochem ical and Solid2state Letters, 2001, 4 (1) : E1 E4.

5 3 : L ibob2pc /DEC 261 The Property Study of L ibob2pc /DEC Electrolyte N ING Ying2kun, YU B i2tao, L I Fu2shen 3, Q IU W ei2hua (D epartm ent of Inorganic N onm etallic M ateria ls, S chool of M aterials Science and Engineering, U niversity of Science and Technology B eijing, B eijing , China) Ab strac t: The new electrolyte salt L ibob for L i2ion battery was synthesized in laboratory, and series of elec2 trolytes of L ibob and PC /DEC was compounded. the temperature and concentration. The conductivity of the electrolytes was compared by changing The cycling perform ance of charging2discharging was also compared by the charging2discharging test, the results showed that the varying regularity of conductivities and cycling stability and capacity were not always identical, but there were a suitable electrolyte for L i/arg cell. The A. C. impedance and CV were used to test the compatibility of the most suitable electrolyte and ARG anode. Conclusion can be drawn that the ARG anode can be p rotected very well by SE I film in 0. 5 mol L - 1 L ibob 2PC /DEC (3 7). Key wo rds: L i2ion battery, Electrolyte, L ibob, PC, DEC