Wang QS, Sun JH, Yao XL, Chen CH (2005b) 4-Isopropyl phenyl diphenyl phosphate as flame-retardant additive for lithium-ion battery electrolyte. Electrochemical and Solid State Letters 8(9), A467-A470. [In English]

Web link:http://dx.doi.org/10.1149/1.1993389

Keywords:

fluorinated alkyl phosphates, non-flammable electrolyte, nonflammable, electrolytes, trimethyl phosphate, cell, cosolvent,

Abstract: To improve the safety of lithium-ion batteries, 4-isopropyl phenyl diphenyl phosphate (IPPP) was used as a flame-retardant additive in a LiPF6 electrolyte solution. The flammability and thermal stability of IPPP-containing electrolytes were investigated by means of burning test and microcalorimetry. It was found that the addition of IPPP can reduce the flammability, and delay the onset temperature of a major exothermal reaction of the electrolyte. Furthermore, the electrochemical performances of LiCoO2/Li cells become slightly worse after using IPPP additive in the electrolyte. This alleviated trade-off between electrolyte flammability, thermal stability, and cell performance provides a possibility to formulate a nonflammable electrolyte containing 5-15 % of IPPP and improve the electrolyte thermal stability with a minimal sacrifice in performance. (c) 2005 The Electrochemical Society. All rights reserved.