Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5150397 | Solid State Ionics | 2017 | 5 Pages |
Abstract
A new class of solvent mixture and new liquid electrolytes are reported. New non-crystallizing materials may improve the performance of lithium-ion batteries at extremely low temperatures. Solvents were prepared by mixing EC (ethylene carbonate) with PEG250 (poly(ethylene glycol) dimethyl ether with an average molar mass of 250 g molâ 1). Some of these mixtures show only a glass transition, which takes place at temperatures below â 70 °C. It is possible to prepare such non-crystallizing electrolytes with both the novel imidazolide lithium salt LiTDI (lithium 4,5-dicyano-2-(trifluoromethyl)imidazolide) and the benchmark commercial salt LiPF6 (lithium hexafluorophosphate). Most state-of-the-art electrolytes crystallize at temperatures above â 40 °C. Thus, below this temperature a rapid decrease in conductivity is observed. New solutions show very good thermal and electrochemical properties (for instance: high conductivity, wide range of electrochemical stability window). This type of electrolyte may also reach high conductivity values of around 0.014 mS cmâ 1 at â 60 °C. This new class of electrolyte may be the answer to the numerous present issues with applications below 0 °C, and also gives the possibility of battery storage at low temperature without cell damage.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Marta Kasprzyk, Aldona Zalewska, Leszek Niedzicki, Anna Bitner, Marek Marcinek, Wladyslaw Wieczorek,