E. Endo et al., Spin trapping study of gradual decomposition of electrolyte solutions for lithium secondary batteries, J ELCHEM SO, 146(1), 1999, pp. 49-53
Spin trapping was used to study the gradual decomposition of electrolyte so
lutions for lithium secondary batteries. After the reductive electrolysis o
f ester-based electrolyte solutions, continuous production of active alkyl
radicals was confirmed by spin trapping, which suggests the existence of a
chain reaction initiated by cathodic polarization of the electrode. Liquid
chromatography confirmed the existence of the produced polymer in electroly
te solutions after 4 weeks of electrolysis. A gradual degradation mechanism
of electrolyte solutions is proposed, in which the polymerization reaction
initiating from the electron transfer equilibrium accompanies the continuo
us production of active alkyl radicals. This is one mechanism for the gradu
al decomposition of electrolyte solutions and could be a cause of the polym
eric components in the surface film on the electrode. (C) 1999 The Electroc
hemical Society. S0013-4651(98)04-078-6. All rights reserved.