ELECTROLYTE FOR CAPACITOR WITH ELECTRIC DOUBLE LAYER AND SUPERCAPACITOR Russian patent published in 2024 - IPC H01G9/04 H01G9/28 H01G11/58 

FIELD: electrical engineering.

SUBSTANCE: invention relates to the field of electrical engineering, namely to an electrolyte and a supercapacitor with a double electric layer with such an electrolyte. Increased service life of organic ionic electrolyte in temperature range from minus 60 °C to plus 65 °C and a supercapacitor at negative temperatures is a technical result, which is achieved due to the fact that the electrolyte contains an ionic liquid and/or a quaternary alkyl ammonium salt with concentration of 0.1–1.4 mol/l, as well as a basic solvent acetonitrile (AN), a modifying additive with a volume fraction of 3–60%, and sodium or potassium benzoate in amount of 0.1–10 wt.%, wherein the quaternary alkylammonium salt is selected from the group containing triethylmethylammonium tetrafluoroborate (TEMA⋅BF4), tetraethylammonium tetrafluoroborate (TEA⋅BF4), 5-azonide spiro[4.4]nonane tetrafluoroborate (SBP⋅BF4), 1,1-dimethylpyrrolidinium tetrafluorbarate (DMP⋅BF4). Modifying additive used can be an organic carbonate or n-propyl acetate (n-PA) ester.

EFFECT: supercapacitor comprises a positive electrode with increased active mass relative to a negative one, which together with the proposed electrolyte formulation provides increased service life of the supercapacitor at negative temperatures.

8 cl, 3 dwg, 4 tbl