We report a polysiloxane based single-ion conducting polymer electrolyte (SIPE) synthesized via hydrosilylation technique. Styrenesulfonyl (phenylsulfonyl) imide groups were grafted on the highly flexible polysiloxane chains followed by lithiation. The highly delocalized anionic charges in the grafted moiety give rise to weak association with lithium ions in the polymer matrix, resulting in lithium ion transference number close to unity (0.89) and remarkably high ionic conductivity (7.2 ×10 -4 Scm -1 ) at room temperature. The high flexibility arising from polysiloxane enables the glass transition temperature (T g ) to be below room temperature. The electrolyte membrane displays high thermal stability and a strong mechanical strength. A coin cell assembled with the membrane comprised of the electrolyte and poly(vinylidene-fluoride-cohexafluoropropene) (PVDF-HFP) performs remarkably well over a wide range of temperature with high charge-discharge rates.12 rule in a three step cyclic process.[36] Following the same mechanism, here, the vinylic part of SPSIK was attached to the polysiloxane chains upon addition of a Si-H bond.The grafting of SPSIK on PMHS chains followed by exchange of K + ions by Li + ions was clearly proven to be successful by FTIR and NMR spectra. As can be seen in the FTIR spectra of PMHS and SG (Fig. 1), the peak at 2167 cm -1 in PMHS, corresponding to Si-H bond, is disappeared in SG, which confirms the grafting of SPSIK. In addition, the peak at 1627 cm -1 in SPSIK, corresponding to the vinylic group, is also disappeared in SG, confirming the grafting, which consumes the vinylic group. Furthermore, the signature signal of Si-H, appears at 4.68 ppm ( 1 H NMR) in PMHS, and the three peaks in the range of 6.78 to 5.31 ppm ( 1 H NMR) in SPSIK corresponding to 3 vinylic protons, are disappeared in SG, validating the grafting of SP on the PMHS chains. [43,46]. Finally, the overall synthesis of SG electrolyte was confirmed by the coherence between the expected and the found values for all the elements, except for Si, in the elemental analysis. The deviation observed for Si is mainly attributed to the incomplete digestion of Si during the analysis, which was also noticed during the elemental analysis of commercial products of Si such as PMHS and poly(methylphenylsiloxane)(PMPS) ( Table S1 in Supporting Information). The GPC analysis of SG in the tetrahydrofuran (THF) mobile phase depicts the number average molecular weight (Mn) of 84,238, weight average molecular weight (Mw) of 150,230, and poly dispersity index (PDI) of 1.78 based on the polystyrene standard.

We report a method to significantly enhance the conductivity of lithium ions in a polymeric lithium salt membrane by introducing functionalized meso/macro-pores to accommodate a mixture of organic solvents in the polymer matrix.

A novel protocol to generate and control porosity in polymeric structures is presented for fabrication of single ion polymer electrolyte (SIPE) membranes for lithium ion batteries. A series of SIPEs with varying ratios of aliphatic and aromatic segments was successfully synthesized and subsequently blended with PVDF-HFP to fabricate membranes of various sizes of pores. The membranes were characterized using techniques including SEM, solvent uptake capacity measurement and ionic conductivity. We demonstrate that appropriate membrane porosity enhances ionic conductivity, reduces interfacial resistance between electrodes and electrolyte and ultimately boosts performance of Li-ion batteries. The implication of the structure-performance relationship for battery design is discussed.

A bis(sulfonyl)imide incorporated, high‐molecular‐weight gel single‐ion polyamide polymer electrolyte (LiPA) is designed and synthesized by using a polycondensation reaction followed by exchange of H+ with Li+ ions. All the bis(sulfonyl)imide anions are immobilized in the polymer chains, which gives rise to a substantially higher lithium cation transference number of 0.88 than the corresponding values of conventional liquid‐based electrolytes or dual‐ion gel polymer electrolytes of inorganic salts, and also provides smooth channels for Li+ ion transport in the polymer matrix. A gel single‐ion polymer electrolyte membrane, comprised of polyvinylidene fluoride (PVDF) and LiPA, is successfully prepared with an ionic conductivity of 3.8×10−4 S cm−1 at room temperature, well suited for applications in lithium‐ion batteries. Good battery performance of the membrane is demonstrated in an assembled Li‐ion battery cell at both room temperature and at elevated temperature.

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Melamine based porous organic frameworks as a single ion conducting electrolyte for lithium ion batteries.

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Summary Fast charge‐discharge rate and high areal capacitance, along with high mechanically stability, are the pre‐requisites for flexible supercapacitors to power flexible electronic devices. In this paper, we have used three‐dimensional polyacrylonitrile graphite foam as flexible current collector for electro‐deposition of polyaniline (PANI) nanowires. The graphite foam with PANI was then used to fabricate symmetric supercapacitor. The fabricated supercapacitor in the three‐electrode system shows a high specific capacitance (Csp) of 357 F.g−1 and areal capacitance (Careal) of 7142 mF.cm−2 in 1 M H2SO4 at current density of 80 mA.cm−2, while using two‐electrode system, it shows Csp of 256 F.g−1 and Careal of 5120 mF.cm−2 in 1 M H2SO4 at current density of 100 mA.cm−2. The current density of 100 mA.cm−2 is up to 10 folds higher than reported current densities of many PANI‐based supercapacitors. The high capacitance can be attributed to the spongy network of PANI‐NWs on three‐dimensional graphite surface which provides an easy path for electrolyte ions in active electrode materials. The developed supercapacitor shows specific energy of 64.8 Whkg−1 and a specific power of 6.1 kWkg−1 with a marginally decrease of 1.6% in Csp after 1000th cycles, along with coulombic efficiency retention of 87% in polyvinyl alcohol/H2SO4 gel electrolyte. This flexible supercapacitor exhibits great potential for energy storage application.