Development of solid polymer polyelectrolyte based on carbonate oligomer

锂离子二次电池用有机溶剂电解液存在漏液或爆炸的危险。有许多研究通过关注粘度或化学结构来提高电导率。然而，支化聚合物对锂离子扩散系数的影响尚未揭示。因此，我们研究了 PC-二醇的电导率和分子量或支化结构之间的关系。电导率随着分子量的降低或温度的降低而增加。 支化和星形聚合物的电导率和粘度低于或高于线性聚合物。电导率和粘度与分子量的变化和支化的引入不成正比。 计算西格玛-eta值是为了消除粘度对西格玛值的影响。 结果，高分子量PC-乙二醇和支链PC-乙二醇表现出更大的幅度。这些效应似乎影响了离子跳跃的难易程度。

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.