Electrolyte for aluminium electrolytic capacitor

Abstract

The aluminum electrolytic capacitor consists of anode aluminum foil, electrolyte paper, cathode aluminum foil, and is produced through winding the electrolyte paper into roll core, soaking the roll core inside electrolyte solution, setting the roll core inside aluminum casing and sealing. The present invention features the electrolyte solution comprising main electrolyte 10-30 wt%, solvent 65-89.95 wt%, and additive 0.05-5 wt%; the main electrolyte of ammonium salt compound and with water content of 15-95 %; the organic solvent of alcohol or ether; and the additive of waterproof compound. Theelectrolyte paper is made of Manila hemp and soaked with the electrolyte solution. The mouth of the aluminum casing is sealed with rubber ring of rubber mixture. The aluminum electrolytic capacitor has electrolyte solution well adsorbed onto the anode aluminum foil and the cathode aluminum foil, no corrosion to leads, high sealing performance and other advantages.

Description

Technical field: [0001] The invention relates to an electrolytic capacitor, in particular to a high-frequency, low-impedance, high-temperature-resistant aluminum electrolytic capacitor and an electrolytic solution for driving. Background technique [0002] Aluminum electrolytic capacitors are composed of coiled anode aluminum foil, electrolytic paper and cathode aluminum foil. The whole device is immersed in the electrolyte, and they are sealed by sealing materials and container shells, and the terminal leads are respectively drawn from the anode aluminum foil and cathode aluminum foil. Existing capacitor structures such as figure 1 As shown, it inserts a layer of electrolytic paper 3 between the anode foil 1 and the cathode foil 2, then rolls it into a cylindrical core, then impregnates the core with electrolyte, and then puts the core into an aluminum shell 6, finally seal the opening of the aluminum shell 6 with a sealing material to prevent leakage of the electrolyte. ...

AI Technical Summary

Problems solved by technology

[0005] In order to develop aluminum electrolytic capacitors with high frequency and low impedance, high temperature resistance (105°C or above), and rated voltage ≤ 100V, some developers used to dissolve phthalic acid or maleic acid in γ-butyrolactone solvent. An aluminum electrolytic capacitor with a salt electrolyte, but when this aluminum capacitor is continuously energized and used in an atmosphere with high humidity, a strongly alkaline compound will be generated at its cathode, and this strongly alkaline compound will especially corrode the cathode wire and The capping material 5 which is in contact with this wire, therefore sometimes causes problems with leakage of electrolyte from the capacitor

In addition, since the resistivity of the γ-butyrolactone system electrolyte is ≥50Ω·cm at 30°C, this also limits the further reduction of the high-frequency impedance of aluminum electrolytic capacitors.

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