The Effect of Liclo4 Concentration on 3d Printed Polyurethane Acrylate Gel Polymer Electrolytes Fabricated Via Stereolithography

To address the demand for high-performance and compact batteries for portable electronics, 3D printing could be leveraged to enhance the polymer electrolytes performance. This work provides a new fabrication method for gel polymer electrolytes (GPEs) through the integration of stereolithography (SLA) 3D printing into the fabrication process while maintaining the GPEs performance. The GPEs were fabricated by dissolving different lithium perchlorate (LiClO4) concentrations (0-25 wt.%) into polyurethane acrylate (PUA) and dimethylformamide (DMF) solution, printed using the SLA method, and then studied the impact of LiClO4 towards the GPEs performance.

The electrical, morphological, and thermal characteristics of the GPEs were characterized through Electrochemical impedance spectroscopy (EIS), Fourier transform infrared (FTIR), X-ray diffraction analysis (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscope (SEM). The 3D printed GPEs exhibited high ionic conductivity at 1.24×10-3 S cm-1 at low LiClO4 concentration (10 wt.%). The result was in line with the number of free ions and amorphous fraction determined by FTIR deconvolution and XRD respectively as both showed the highest value at 10 wt.% LiClO4. Besides, the addition of LiClO4 into GPEs polymer matrix causes a shift in urethane, ether, and carbonyl functional groups. The 3D GPEs were thermally stable until it reached a temperature of around 300 oC.

As 10 wt.% sample was determined to have the best performance, the formulation was used to fabricate 3D structure GPEs to test its printability which is the most important characteristic for 3D printing. The formulation was successfully printed into three different designs; honeycomb, interdigated, and scaffold structures which indicates that the integration of 3D printing into GPEs fabrication was successful. The ability to construct 3D structures of electrolytes is important as it can significantly improve battery performance by providing a larger contact area with electrodes.