結晶ポリマーの電解質におけるイオン伝導度 PEO6:LiXF6,X = P,As,Sb

Zlatka Stoeva¹, Isabelle Martin-Litas, Edward Staunton

¹School of Chemistry, University of St. Andrews, Purdie Building, North Haugh, St. Andrews KY16 9ST, UK.

Journal of the American Chemical Society

|April 10, 2003

まとめ

結晶ポリマー電解質はイオンを伝導し,無形物質のみが伝導性を持つという見解に異議を唱える. これらの固体材料は,先進的なリチウム電池技術に希望を示しています.

科学分野:

材料科学材料科学とは
電気化学電気化学について
ポリマーサイエンスの科学

背景:

イオン伝導ポリマーは固体イオン伝導性を提供し,リチウム電池などのデバイスにとって不可欠です.
伝統的に,ポリマーのイオン伝導性は,ガラスの移行温度以上の無形相と関連付けられています.
結晶ポリマーの電解質は,広く隔離剤と考えられていた.

研究の目的:

結晶ポリマー電解質のイオン伝導性を調査する.
ポリマー電解質におけるイオン輸送に関する確立された理解に異議を唱える.
バッテリーアプリケーションのための結晶ポリマー電解質の構造-特性関係を調査する.

主な方法:

結晶型ポリマー電解質の合成と特徴付け:ポリエチレン酸化物) (6):LiXF6) (X = P,As,Sb).
結晶と無形相におけるイオン伝導性の測定.
伝導経路を理解するために結晶構造の分析.
離子伝導性に対する分子量の影響に関する研究.

主要な成果:

3つの結晶ポリマー電解質 (ポリエチレン酸化物) (6:LiXF6) で有意なイオン伝導性が実証されています.
同様の無形相と比較して,結晶相ではより高いイオン伝導性が観察されました.
結晶構造のボトルネックと相関する6:1複合体の間でも同様の伝導性を発見しました.
結晶石のサイズが大きいため,分子量が減少したイオン伝導性が増加したと報告されています.

結論:

結晶ポリマー電解質は,以前の仮定に反して,かなりのイオン伝導性を示すことができます.
イオン伝導性は,ポリマーの分子量と結晶体の大きさによって影響されます.
これらの発見は,エネルギー貯蔵装置のための先進的な固体電解質を開発するための新しい道を開きます.

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