# Development on Solid Polymer Electrolytes for Electrochemical Devices
## 3 Basic Solid Polymer Electrolytes
### Strategies to Improve Ionic Conductivity of SPEs
#### 3.2.5 Plasticized Solid Polymer Electrolytes
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Electrolyte System** & **Preparation Method** & **Conductivity, \(\sigma\) (S cm\({}^{-1}\))** & **Important Findings** & **Reference** \\ \hline PEMA-NH4I-EC & Solution casting & \(1.16\times 10^{-5}\) (RT) & \(t_{ion}\) = 0.85 & \\  & & \(n\) = 1.75 \(\times\) 10\({}^{21}\) m\({}^{-3}\) & [110] \\ \hline PEMA-NH4 CF3 SO3- & Solution casting & \(8.35\times 10^{-4}\) (30 \({}^{\circ}\)C) & \(T_{g}\) = 2 \({}^{\circ}\)C; \(t_{ion}\) = 0.82 & \\  & & & Unplasticized SPE: & [111] \\  & & & \(\sigma\) = 1.02 \(\times\) 10\({}^{-5}\) S cm\({}^{-1}\); \(T_{g}\) = 68 \({}^{\circ}\)C & \\ \hline PVDF-HFP-LiClO4-SN & Solution casting & \(\sim\)1.62 \(\times\) 10\({}^{-3}\) (20 \({}^{\circ}\)C) & \(E_{A}\) = 0.40 eV & \\  & & & Unplasticized SPE: & [105] \\  & & & \(\sigma\) = \(\sim\)6.38 \(\times\) 10\({}^{-9}\) S cm\({}^{-1}\) (20 \({}^{\circ}\)C) & \\  & & & \(E_{A}\) = 0.69 eV & \\ \hline  & & & LiCoO2/SPE/LiTaSiO12 cell (C/10, & \\ PVDF-HFP-LiBETI-SN & Solution casting & \(\sim\)2.58 \(\times\) 10\({}^{-3}\) (20 \({}^{\circ}\)C) & Initial discharge capacity & [105] \\  & & & 116 mAh g \({}^{-1}\), 78\% capacity & \\  & & & retention after 120 th cycle & \\ \hline  & & & \(T_{g}\) = \(-\)75.6 \({}^{\circ}\)C; \(t_{Li}\)\({}_{+}\) = 0.37 (25 \({}^{\circ}\)C) & \\ PVDF-PEO-LiClO4-SN & Solution infiltration & & LiFePO4/SPE/Li: & \\  & in PVDF film + drying & 2.80 \(\times\) 10\({}^{-5}\)(25 \({}^{\circ}\)C) & OCV = 3.1 V, discharge capacity & \\  & & drying & 109 mAh g \({}^{-1}\) (100 th cycle), 90\% & \\  & & & capacity retention & \\ \hline PEO-LiCF3 SO3-TiO2- & Solution casting & \(1.60\times 10^{-4}\) (30 \({}^{\circ}\)C) & \(E_{A}\) = 0.60 eV; \(T_{g}\) = \(-\)50 \({}^{\circ}\)C; \(T_{m}\) = 50 \({}^{\circ}\)C & [43] \\  [EO]/[Li] = 9:1 & & & Unblended PEO-KI SPE: & \\  & & & \(\sigma\) = 1.96 \(\times\) 10\({}^{-5}\) S cm\({}^{-1}\) (25 \({}^{\circ}\)C) & \\  & & & Low M\({}_{\rm w}\) of PEG (\(\sim\)4000) might be & [113] \\  & & & trapped or crosslink in PEO-KI & \\  & & & network & \\ \hline PEO-LiTFSI-S2 TFSI & Mixing, vacuum-sealed in pouch and hot press & \(0.96\times 10^{-3}\) (22 \({}^{\circ}\)C) & \(t_{Li+}\) = 0.31 (60 \({}^{\circ}\)C) & \\  & & & LiFePO4/SPE/Li: & \\  & vacuum-sealed in pouch and hot press & \(4.00\times 10^{-3}\) (60 \({}^{\circ}\)C) & Discharge capacity (1 C, 60 \({}^{\circ}\)C) = & [114] \\  & & & 160.1 mAh g\({}^{-1}\) (500 th cycle), 89.9\% & \\  & & & capacity retention & \\ \hline  & & & \(T_{g}\) = \(-\)58.1 \({}^{\circ}\)C; \%\(\times\)XC = 24.7\% & \\  & & & High thermal stability with & \\  & & & decomposition temperature above & \\  & & & 220 \({}^{\circ}\)C & \\ PEO-LiFSI-N1222 FSI & Solution casting & \(1.78\times 10^{-5}\) (25 \({}^{\circ}\)C) & LiFePO4/SPE/Li: & \\
[EO]/[Li] = 20:1 & & \(2.14\times 10^{-4}\) (50 \({}^{\circ}\)C) & Discharge capacity (0.2 C, 50\({}^{\circ}\)C) = & [115] \\  & & & 151.5 mAh g\({}^{-1}\) (120 th cycle), 95.4\% & capacity retention \\  & & & Unplasticized SPE: & \\  & & & \(\sigma\) = 7.24 \(\times\) 10\({}^{-7}\) S cm\({}^{-1}\) (25 \({}^{\circ}\)C) & \\  & & & \(T_{g}\) = \(-\)44.8 \({}^{\circ}\)C; \%\(\times\)XC = 33.6\% & \\ \hline PEO:MC & & & \(E_{A}\) = 0.0322 eV & \\ (60:40)-NH4I-PEG & Solution casting & \(3.37\times 10^{-3}\) (30 \({}^{\circ}\)C) & Unplasticized SPE: & \\  & & & \(\sigma\) = 7.62 \(\times\) 10\({}^{-5}\) S cm\({}^{-1}\) (30 \({}^{\circ}\)C) & [116, 117] \\  & & & \(E_{A}\) = 0.0465 eV & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: _Cont._