Lithium-doped hybrid polymer electrolyte

de ZEA BERMUDEZ,University of Tras-os-Montes e Alto Douro, Portugal, and M. M. SILVA, University of Minho, Portugal 

Abstract The interest in sol-gel derived polymer/siloxane hybrid electrolytes has grown considerably during the last decade because of their potential application in sohd state electrochemical devices, in particular batteries and electrochromic devices (ECDs).This review intends to provide an overview of the latest advances in the investigation of the structure, morphology, thermal properties, electrochemical behavior and spectroscopic features of Li -coutaiuiug di-urea crosslinked polyoxyethylene (POE)/siloxane (di-ureasil) electrolytes. Applications of these materials in ECDs will be addressed. 

Key words hybrid electrolytes, sol-gel, lithium salts, characterization, electrochromic devices. 

The interest in polymer electrolytes (PEs) has not ceased to increase since the first report of salt/polymer complexes by Wright and the subsequent recognition by Armand et al of the potential use of these materials as electrolytes in solid state electrochemical devices.  

The practical application of POE-based electrolytes in solid state electrochemical devices has been delayed by two main drawbacks their poor processability and marked tendency to crystallize. The latter aspect is particularly limiting. POE/salt complexes are usually crystalline, but pristine POE is itself already semicrystalline. For nearly two decades the view that 

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Lithium-doped hybrid polymer electrolytes 197 out-of-phase (B) components because of the coupling between the two SO2... 

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