| 摘要 |
Improved nonaqueous electrolytes for application in electrical storage devices such as electrochemical capacitors or high energy density batteries are disclosed. The electrolytes of the invention contain salts comprising alkyl substituted (wherein at least one alkyl group consists of five or more carbon atoms), cyclic delocalized heterocyclic cations, their perfluoro derivatives, and certain polyatomic anions, preferably inorganic perfluoro anions, these salts either used neat, or dissolved in organic solvents, preferably organic carbonate solvents, or liquid inorganic gases or combinations thereof, at a concentration of greater than 0.5M and preferably greater than 1.0M. Exemplary electrolytes comprise 1-methyl-3-<i>n</i>-pentylimidazolium hexafluorophosphate dissolved in a cyclic or acyclic organic carbonate, or methyl formate, or a combination thereof. These salts and these improved electrolytes have useful characteristics such as enhanced oxidative stability, wider liquid range, a wider electrochemical window, and high energy storage capabilities and power characteristics compared to prior art electrolytes. Electrochemical double layer capacitors using electrolytes of this invention permit high energy storage at high voltages. |
