Polymer electrolytes were prepared with hyperbranched polyurethane and linear polyurethane as the host polymer and LiClO4 as the ion source．FTIR spectra was used to analyze the bending degree of Li+ with carbonyl and ether groups．It Was found that Li+ preferred bonding with the ether group

and bonded with the carbonyl group when the salt concentration reached a certain level．The bending degree of Li+ with ether groups and the carbonyl groups both reached a saturated state at a salt concentration of EO／Li+=4．Raman spectra was applied to analyze the aggregation degree of anions ClO-4. The fraction of contact-ion pairs increased with increasing salt concentration．When the salt concentration increased to EO／Li+=4

the salt aggregates appeared

but the area fraction of aggregates was merely 1.2％．This indicated that the hyperbranched polyurethane could function as a” solvent” for the lithium salt．Conductivity analysis indicated that the conductivity kept increasing with increasing concentration of HPU and the conductivity maximum of the present system appeared at a higher salt concentration (EO／Li+=4) which could be attributed to the high solvating capability of the hyperbranehed polymer．The ionic conductivity of all samples was apparently enhanced with increasing temperature

and the Arrhenius phenomenological relationship could be used to describe the conductivity behavior.