Solid and gel polymer electrolytes for application in lithium and lithium-ion batteries modified with organic derivatives of boron and aluminum

Aim of project
The main purpose of the project is to obtain a new group of polymer electrolytes (in the form of thin membranes), characterized by lithium cations transference number close to unity. Within this project we attempt to limit or eliminate anion mobility by complexing them with boron or aluminum compounds of Lewis acid properties. At the same time we expect that an increase in the salt degree of dissociation, decrease in share of ionic associates and increase in cation mobility (which should provide the electrolytes with considerably higher conductivity with respect to that of polyelectrolytes) will be additional effects of such an interaction.

Within the project, the ability of the aluminum and boron receptors obtained towards the immobilization of salt anions in gel electrolytes, i.e. systems containing a lithium salt solution in polar solvent encapped in the polymer network, will be studied. This type of electrolytes are at present used as membranes in the produced lithium and lithium-ion batteries. The polarization phenomenon, due to anion accumulation in the near-electrode region, is still a problem limiting the obtained cell parameters.

Expected results
The results of the studies carried out will be utilized for the development of an original system of high cation transference numbers (t+ > 0.8) and acceptable ionic conductivity (of the order of 10−5–10−4 S/cm at 30°C) and preliminary estimation of their applicability for use in lithium batteries.

Preliminary studies illustrating some general phenomena occurring in polymer electrolytes modified with boron and aluminum products will be published in polymer journals and presented at conferences.