Higher cationic transference number is preferred for electrolytes of lithium ion batteries

and employing maeromolecular lithium salt is effective to improve the cationic transference number of the electrolytes．Therefore

a novel macromolecular lithium salt was synthesized through sulfation and neutralization of hyperbranehed pofyglyeidul．which was obtained by cationic ring-opening polymerization．13C-NMR analysis indicates the degree of branching of polyglycidol is about 0.5．and element analysis confirms the degree of substitution of hydroxyls can excess 0.6 after sulfation．FTIR and thermal analysis were used to characterize the hyperbranched polyglycidol and the macromolecular lithium salt derived from it For the application of this nmeromolecular lithium salt in lithium ion batteries．viscosity and conductivity of its solution in the mixed solvent of EC/PC/DMF were studied．The results show that the viscosity of its dilute solution is so low that it can be compared with that of small molecular lithium salts However．when the concentration of the solution is increased above 10％．the viscosity of the solution increases quickly and reaches a very high level at the concentration of about 30％．There exists a maximal conductivity of the solution while the concentration of the solution increases．and the maximum is reached at a concentration of about 10％．This can be explained by the concentration and mobility of free lithium ions in the solution．Besides．the maximal conductivity of the solution is about 1.7 mS/cm at 25℃．which can be compared with that of small molecular lithium salts．Considering the low viscosity and the high conductivity of its dilute solution

this macromolecular lithium salt has great potential application in inlithium ion batteries．