## 3 Results and Discussion
### Ionic Conductivity  
The ionic conductivities of the formulated electrolytes were measured by the complex impedance method using an impedance analyzer (Solartron model SI-1287) coupled to a Solartron model-1260 frequency response analyzer [29]. The solid electrolyte membranes were sandwiched between two stainless steel electrodes for conductivity measurements [10; 30]. All measurements were performed in an environmental chamber in the temperature range of 25-70 \({}^{\circ}\)C [31]. \begin{table}
\begin{tabular}{c c c c c c c c} \hline
**Sample** & **a** & **b** & **c** & **d** & **e** & **f** & **g** \\ \hline T\({}_{\text{g}}\) [\({}^{\circ}\)C] & \(-49.2\) & \(-48.5\) & \(-49.6\) & \(-50.3\) & \(-48.9\) & \(-50.6\) & \(-50.9\) \\ T\({}_{\text{m}}\) [\({}^{\circ}\)C] & 61.7 & 55.2 & 44.8 & 52.2 & 43.7 & 52.8 & 47.7 \\ \hline \end{tabular}
\end{table} 
Table 6: Thermal properties of the PSLS-based electrolytes membranes. Figure 9: Heat flow versus temperature of the differential scanning calorimetry DSC curves: (**a**) weight ratio of PEO:PEGDM:LiTFSI (PPL) = 3:4.2, (**b**) weight ratio of PSTSIL:PEO:PEGDM:LiTFSI (TFSI–PPL) = 1:3:4:2, (**c**) weight ratio of TFSI–PPL = 1:3:4:3, (**d**) weight ratio of TFSI–PPL = 2:3:4:3, (**e**) weight ratio of TFSI–PPL = 3:3:4:3, (**f**) weight ratio of SPHTSIL:PEO:PEGDM:LiTFSI (PHSI–PPL) = 1:3:4:3, (**g**) weight ratio of PSDTTOL:PEO:PEGDM:LiTFSI (DTTO–PPL) = 1:3:4:3, (**h**) four best performing membranes, (**i**) various weight ratios of PSTSILi. To compare the performance of our electrolytes, we compared the data with that of similar work published in the literature. For example, [PERSON] et al. reported a single-ion BAB triblock copolymer, P(STFSILi)-PEO-P(STFSILi) that displayed very good ionic conductivity of \(1.3\times 10^{-05}\) S cm\({}^{-1}\)[32]. In another study, [PERSON] et al. developed a similar single lithium-ion conducting polymer electrolyte based on the poly[(4-styrenesulfonyl)(trifluoromethane sulfonyl)imide] anion. However, the ionic conductivities could only reach \(7.6\times 10^{-06}\) S cm\({}^{-1}\) at 25 \({}^{\circ}\)C and \(10^{-04}\) S cm\({}^{-1}\) at 60 \({}^{\circ}\)C [23]. In this study, the ionic conductivity of TFSI-PPL (Figure 9) at the weight ratio of 1:3:4:3 displayed \(3.0\times 10^{-03}\) S cm\({}^{-1}\) at 70 \({}^{\circ}\)C, which is superior to that of the PhSI-PPL at \(1.27\times 10^{-03}\) S cm\({}^{-1}\). The best ionic conductivity of \(3.23\times 10^{-03}\) S cm\({}^{-1}\) at 70 \({}^{\circ}\)C was achieved with DTTO-PPL at the weight ratio of 1:3:4:3. Among the three PSLSs, the compounds containing PSTFSI and PSPhSI showed structural similarity as both contained a nitrogen anionic site. The higher ionic conductivity of the TFSI-PPL electrolyte was due to the presence of the CF\({}_{3}\) group, which induced a strong electron-withdrawing effect when compared to an aromatic ring. In contrast, the existence of three strong electron withdrawing sulfone (SO\({}_{2}\)) groups provided the PSDTTO anion with the best dissociating ability to enable faster lithium ion transport. As the temperatures were elevated, the movement of the polymer chain segments rapidly increased, and all of the salts followed the well-established trend of increasing conductivity with the increase in temperatures (Figures 10-13). Nevertheless, with the increasing weight ratio of PSLSs, the conductivity decreased. This trend can likely be attributed to the high salt concentration with the additional influence of the ion pairs, ion triplets, and the higher ion aggregations, which reduced the overall mobility and the number of effective charge carriers [1]. It is important to note that our assessment was based on the formulation that provided the highest ionic conductivity. PPL displayed its highest ionic conductivity with the formulation described in Table 2 (i.e., PEO:PEGDM:LiTFSI:3:4:2). The TFSI-PPL and DTTO-PPL based electrolytes displayed the best ionic conductivity with this formulation (1:3:4:3, see Tables 2 and 4).