Composite Polymer Electrolytes Based on Hyperbranched Polymer and Application to Lithium Polymer Batteries

Solid polymer electrolytes based on comblike polymers

“…1 and 2 shows the temperature dependence of the ionic conductivity for the (90%PEO-10%poly-4) x (LiN(CF 3 SO 2 ) 2 ) electrolyte and the (90%PEO-10%(poly-4/TCNQ)) x (LiN(CF 3 10 (LiN(CF 3 SO 2 ) 2 ) electrolyte, respectively, at three different comblike polymer contents of 5, 10, and 20 wt%.…”

“…Recently, we have attempted to use hyperbranched polymers (HBPs) as a plasticizer for the PEO-based polymer electrolytes because HBPs are completely amorphous, highly soluble in common organic solvent and they have many branch-ends in favor of ion transport because of rapid motion. The composite polymer electrolytes composed of PEO, BaTiO 3 as a ceramic filler, LiN(CF 3 SO 2 ) 2 as a lithium salt, and HBP (poly[bis(triethylene glycol)benzoate] capped with acetyl groups) as a plasticizer showed the high ionic conductivity at room temperature because of effective suppression of crystallization of PEO by HBP and also has high electrochemical and thermal stabilities [9,10]. The comblike polymers are similar to the HBP in the point of the chemical structures having many chain ends, and they are expected to contribute to the ion transport and also to act as an effective plasticizer to enhance ionic conductivity at a low temperature region like as HBPs for the PEO-based polymer electrolytes.…”

Degree of Branching of Highly Branched Polyurethanes Synthesized via the Oligomeric A2 Plus B3 Methodology

“…[21,22] A variety of polyethers (i.e., PEG, PTMO, PPG) were ionically conductive in the presence of a metal salt; however, PEG has the highest ionic conductivity. [23][24][25][26] Previous efforts to introduce branching in PEG-based polymers for solid polymer electrolyte applications have included the synthesis of comb-burst PEG and the incorporation of small amounts of hyperbranched PEG-based poly(urethane urea)s with linear poly(urethane urea)s. [13,27] The hard segment of the highly branched poly(ether urethane)s was comprised of dicyclohexylmethane-4, 4 0 -diisocyanate (HMDI) and TMP. An isocyanate endcapped prepolymer was synthesized through the reaction of two equivalents of HMDI and one equivalent of polyether.…”

Solid polymer electrolytes based on squaric acid structure

“…Effect of PPS polymer as an additive on the PEO-based polymer electrolyte Previously, we investigated the effect of a hyperbranched polymer as an additive for the PEO-based polymer electrolytes and found that it might behave effectively as a plasticizer to suppress the crystallization of PEO [9][10][11]. The PPS-based polymer electrolytes are completely amorphous as mentioned above.…”

“…To overcome this disadvantage for the PEO-based polymer electrolytes, considerable research efforts, for example, forming networks, copolymers with other units, and adding plasticizers such as propylene carbonate, ethylene carbonate, oligomeric PEO, hyperbranched polymers, and inorganic fillers, have been made. As the ionic transport in the PEO-based polymer electrolytes is strongly coupled with the segmental motion of the polymer, many types of polymers with low glass transition temperatures have been developed to aim for the practical battery applications [5][6][7][8][9][10][11]. On the other hand, it was reported that the polymer electrolytes composed of a very rigid polymer such as a poly(vinylene carbonate) with lithium salts might exhibit the ionic transport decoupled from the segmental motion of the polymer, being different from the mechanism in the PEO-based polymer electrolytes [12].…”