WORKING ELECTROLYTE FOR CONDENSER, METHOD OF ITS PREPARATION AND ALUMINUM ELECTROLYTIC CAPACITOR WITH SUCH ELECTROLYTE Russian patent published in 2020 - IPC H01G9/145 H01G9/45 H01G11/58 

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering, namely to aluminum oxide-electrolytic capacitor for rated voltage of 160–450 V with operating temperature range from minus 60 to plus 125 °C, as well as to working electrolyte for it and method of electrolyte preparation. Working electrolyte contains: a mixture of organic solvents based on gamma-butyrolactone, a co-solvent selected from pyrrolidones, nitriles, cyclic carbonates, formamides for reducing freezing temperature, co-solvent for improving separator wettability by working electrolyte selected from polyatomic alcohols or ethers, inorganic acid, or its salt, or oxide, having acid properties, carboxylic acid, amine, gas-absorbent additive and water, wherein the main solvent occupies 30–70 wt%, co-solvent for lowering freezing point of working electrolyte – 10–40 wt%, cosolvent for improvement of separator wettability – 1–10 wt%, inorganic acid, or its salt, or acid oxide – 1–10 wt%, carboxylic acid – 0.5–10 wt%, amine – 0.5–10 wt%, gas-absorbent additive – 0.5–7 wt%, water – 0.1–2.5 wt%. Method of preparing working electrolyte involves loading γ-buitroylactone into reactor at ambient temperature, mixing it at rate of 60 rpm, loading co-solvents, nitroanisole and inorganic acid, stirring mixture until complete dissolution, heating mixture not higher than 115 °C, loading amine, stirring until complete dissolution, loading carboxylic acid, stirring until complete dissolution, heating mixture to temperature equal to or greater than 125 °C, and cooling mixture to ambient temperature with constant stirring.

EFFECT: low resistance and tangent of the dielectric loss angle of the aluminum electrolytic capacitor, as well as high stability of characteristics of the working electrolyte and capacitor in the temperature range from minus 60 to plus 125 °C during the entire service life of the capacitor.

9 cl, 9 tbl