Zheng Qi, Ma Lin, Khurana Rachna, Archer Lynden A, Coates Geoffrey W
Department of Chemistry and Chemical Biology , Baker Laboratory , Cornell University , Ithaca , New York 14853 , USA . Email:
Department of Materials Science and Engineering , Cornell University , Bard Hall , Ithaca , New York 14853 , USA.
Chem Sci. 2016 Nov 1;7(11):6832-6838. doi: 10.1039/c6sc01813k. Epub 2016 Jul 19.
Lithium dendrite growth is a fundamental problem that precludes the practical use of lithium metal batteries. Solid polymer electrolytes (SPEs) have been widely studied to resist the growth of lithium dendrites but the underlying mechanisms are still unclear. Most SPEs sacrifice high ionic conductivities for increased dendrite suppression performance by using components with high mechanical stiffness. We report a class of cross-linked hydrocarbon/poly(ethylene oxide) SPEs with both high ionic conductivities (approaching 1 × 10 S cm at 25 °C) and superior dendrite suppression characteristics. A systematic structure-property study shows that the crystallinity of the hydrocarbon backbones plays a key role in regulating size and morphology of lithium dendrites, as well as the ability to suppress their growth.
锂枝晶生长是阻碍锂金属电池实际应用的一个基本问题。固态聚合物电解质（SPEs）已被广泛研究以抑制锂枝晶的生长，但其潜在机制仍不明确。大多数固态聚合物电解质通过使用具有高机械刚度的组分来牺牲高离子电导率以提高枝晶抑制性能。我们报道了一类具有高离子电导率（在25℃时接近1×10 S cm）和优异枝晶抑制特性的交联烃/聚环氧乙烷固态聚合物电解质。一项系统的结构-性能研究表明，烃主链的结晶度在调节锂枝晶的尺寸和形态以及抑制其生长的能力方面起着关键作用。
