Development of solid polymer polyelectrolyte based on carbonate oligomer

锂离子二次电池有机溶剂电解液存在液体泄漏或爆炸的危险。有很多研究是通过粘度或化学结构来提高导电性的。然而，支化聚合物对锂离子扩散系数的影响并未被揭示。因此，我们研究了电导率与PC-二醇的相对分子质量或支化结构的关系。电导率随相对分子质量的降低或温度的降低而增大。支化聚合物和星形聚合物的电导率和粘度均低于或高于线型聚合物。电导率和粘度与相对分子质量和支链引入的变化不成正比。计算了Sigma-ETA值，以消除粘度对Sigma值的影响。结果表明，高相对分子质量的聚碳酸酯和支链聚乙二醇组分的含量较大。这些效应似乎影响了离子跃迁的容易程度。

The organic solvent electrolyte for lithium ion secondary battery has the danger of liquid leaking or explosion. There are many studies to increase the conductivity by focus on viscosity or chemical structure. However, the effect of branched polymer on the diffusion coefficient of lithium ions was not revealed. Thus, we investigated the relationship between conductivity and molecular weight or branched structure of the PC-glycols. The conductivity increased with a decrease of molecular weight or decrease of temperature. Conductivity and viscosity of branched and star polymer was lower or higher than that of linear polymer. Conductivity and viscosity was not proportional to the change of molecular weight and introduce of branch. The sigma-eta value was calculated in order to cancel the viscosity effect on the sigma value. As the results, the high molecular weight-PC-glycol and branched one exhibited larger magnitude. It seems that these effects influenced the ease of ion hopping.