Cresyl diphenyl phosphate effect on the thermal stabilities and electrochemical performances of elec

Abstract To improve the safety of lithium ion battery, cresyl diphenyl phosphate (CDP) is used as a flame-retardant additive in a LiPF 6 based electrolyte. The electrochemical performances of LiCoO 2 /CDP-electrolyte/Li and Li/CDP-electrolyte/C half cells are evaluated. The thermal behaviors of Li 0.5 CoO 2 and Li 0.5 CoO 2 –CDP-electrolyte, and Li x C 6 and Li x C 6 –CDP-electrolyte are examined using a C80 micro-calorimeter. For the LiCoO 2 /CDP-electrolyte/Li cells, the onset temperature of single Li 0.5 CoO 2 is put off and the heat generation is decreased greatly except the one corresponding to 5% CDP-containing electrolyte. When Li 0.5 CoO 2 coexists with CDP-electrolyte, the thermal stability is enhanced. CDP improves the thermal stability of lithiated graphite anode effectively and the addition of 5% CDP inhibits the decomposition of solid electrolyte interphase (SEI) films significantly. The electrochemical tests on LiCoO 2 /CDP-electrolyte/Li and Li/CDP-electrolyte/C cells show that when less than 15% CDP is added to the electrolyte, the electrochemical performances are not worsen too much. Therefore, the addition of 5–15% CDP to the electrolyte almost does not worsen the electrochemical performance of LiCoO 2 cathode and graphite anode, and improves theirs thermal stability significantly; thus, it is a possible choice for electrolyte additive.

[1]  J. Yamaki,et al.  Thermal stability of propylene carbonate and ethylene carbonate–propylene carbonate-based electrolytes for use in Li cells , 2002 .

[2]  Seung-wook Eom,et al.  Thermal and electrochemical behaviour of C/LixCoO2 cell during safety test , 2008 .

[3]  Jean-Marie Tarascon,et al.  Development of Reliable Three-Electrode Impedance Measurements in Plastic Li-Ion Batteries , 2001 .

[4]  R. Spotnitz,et al.  Abuse behavior of high-power, lithium-ion cells , 2003 .

[5]  S. Chakraborty,et al.  Thermal runaway inhibitors for lithium battery electrolytes , 2006 .

[6]  Qingsong Wang,et al.  Enhancing the thermal stability of LiCoO2 electrode by 4-isopropyl phenyl diphenyl phosphate in lithium ion batteries , 2006 .

[7]  Qingsong Wang,et al.  Improved thermal stability of lithium ion battery by using cresyl diphenyl phosphate as an electrolyte additive , 2010 .

[8]  Qingsong Wang,et al.  Thermal Behavior of Lithiated Graphite with Electrolyte in Lithium-Ion Batteries , 2006 .

[9]  Shengbo Zhang.  A review on electrolyte additives for lithium-ion batteries , 2006 .

[10]  H. Ota,et al.  Effect of cyclic phosphate additive in non-flammable electrolyte , 2003 .

[11]  Kang Xu,et al.  Tris(2,2,2-trifluoroethyl) phosphite as a co-solvent for nonflammable electrolytes in Li-ion batteries , 2003 .

[12]  Chusheng Chen,et al.  Electrolyte additive trimethyl phosphite for improving electrochemical performance and thermal stability of LiCoO2 cathode , 2006 .

[13]  Qingsong Wang,et al.  4-Isopropyl Phenyl Diphenyl Phosphate as Flame-Retardant Additive for Lithium-Ion Battery Electrolyte , 2005 .