Search

CN-122000206-A - Liquid aluminium electrolytic capacitor

CN122000206ACN 122000206 ACN122000206 ACN 122000206ACN-122000206-A

Abstract

The application discloses a liquid aluminum electrolytic capacitor, and relates to the technical field of electrolytic capacitors. The liquid aluminum electrolytic capacitor is manufactured by the following steps of sequentially overlapping and winding anode foil, first electrolytic paper, cathode foil and second electrolytic paper into a core package, carrying out electrolyte impregnation treatment on the core package, and packaging the core package to obtain the liquid aluminum electrolytic capacitor, wherein the electrolyte at least comprises the following raw materials, by mass, 60-75 parts of N, N-dimethylformamide, 15-25 parts of ethylene glycol, 3-5 parts of boric acid, 1.5-3 parts of ammonium formate, 1-3 parts of silicon-boron modified polyethylene glycol adipate, 0.5-1.5 parts of triethylamine, 0.3-0.7 part of ammonium hypophosphite and 0.2-0.5 part of p-nitrobenzoic acid. The electrolyte prepared by the application endows the liquid aluminum electrolytic capacitor with wide temperature range adaptability, high voltage tolerance and long service life stability.

Inventors

  • WANG YONGMING

Assignees

  • 上海永铭电子股份有限公司

Dates

Publication Date
20260508
Application Date
20260408

Claims (7)

  1. 1. The liquid aluminum electrolytic capacitor is characterized by being manufactured by the following method: sequentially overlapping and winding the anode foil, the first electrolytic paper, the cathode foil and the second electrolytic paper into a core package; carrying out impregnation electrolyte treatment on the core package, and obtaining a liquid aluminum electrolytic capacitor after the core package is put into a shell and packaged; the electrolyte at least comprises the following raw materials in parts by mass: 60-75 parts of N, N-dimethylformamide, 15-25 parts of ethylene glycol, 3-5 parts of boric acid, 1.5-3 parts of ammonium formate, 1-3 parts of silicon-boron modified polyethylene glycol adipate, 0.5-1.5 parts of triethylamine, 0.3-0.7 part of ammonium hypophosphite and 0.2-0.5 part of p-nitrobenzoic acid.
  2. 2. The liquid aluminum electrolytic capacitor as recited in claim 1 wherein the method for preparing the silicon-boron modified polyethylene adipate comprises at least the following steps: Mixing adipic acid, glycol and gamma-aminopropyl triethoxysilane triethyl borate, introducing nitrogen to perform a step heating reaction, closing the nitrogen to perform a polycondensation reaction under negative pressure, and cooling to obtain the silicon-boron modified polyethylene glycol adipate.
  3. 3. The liquid aluminum electrolytic capacitor according to claim 2, wherein a molar ratio of the adipic acid, the ethylene glycol, the γ -aminopropyl triethoxysilane, and the triethyl borate is 3-5:2-4:0.2-0.5:0.1-0.4.
  4. 4. The liquid aluminum electrolytic capacitor as recited in claim 2, wherein the step-wise temperature-increasing reaction is set to be performed at 150-155 ℃ for 2-3 hours and at 165-175 ℃ for 2-3 hours.
  5. 5. The liquid aluminum electrolytic capacitor as recited in claim 2, wherein the polycondensation reaction is carried out at a temperature of 220 to 230 ℃ for 3 to 5 hours and at a pressure of 20 to 30kPa.
  6. 6. The liquid aluminum electrolytic capacitor as recited in claim 1, wherein the impregnated electrolyte is at a temperature of 80-90 ℃ for a time of 30-60min.
  7. 7. The liquid aluminum electrolytic capacitor according to claim 1, wherein the method for preparing the electrolytic solution comprises at least: heating N, N-dimethylformamide, ethylene glycol, boric acid, ammonium formate and triethylamine to 110-120 ℃, stirring at constant temperature for 60-100min, cooling to 75-90 ℃, adding silicon-boron modified polyethylene glycol adipate, ammonium hypophosphite and p-nitrobenzoic acid, stirring at constant temperature for 10-30min, and cooling to room temperature to obtain the electrolyte.

Description

Liquid aluminium electrolytic capacitor Technical Field The invention relates to the technical field of electrolytic capacitors, in particular to a liquid aluminum electrolytic capacitor. Background With the rapid development of electronic component research, aluminum electrolytic capacitors are gradually developed toward miniaturization, wide temperature range, long service life and high safety. Aluminum electrolytic capacitors are one of the extremely important basic electronic components, and play a special role in not only the roles of filtering, coupling and bypass in electronic circuits, but also correction circuits and power supply circuits. With the deep research of aluminum electrolytic capacitors, the temperature requirements for devices are gradually increased, the temperature range of the devices is developed from the earliest 0-80 ℃ to the current-55-105 ℃, and the voltage resistance requirements for the devices are also gradually increased. The aluminum electrolytic capacitor mainly comprises a capacitor core and working electrolyte. The electrolyte plays a critical role in the performance of the capacitor, and determines the working temperature range, rated voltage, loss, impedance, ripple current, working life and the like of the capacitor. The electrolyte is an actual cathode of the aluminum electrolytic capacitor and plays roles in providing oxygen ions and repairing an anodic oxide film, so that the high-performance electrolyte plays a vital role in ensuring the quality of the aluminum electrolytic capacitor. The solute, the solvent and the additive form the electrolyte of the aluminum electrolytic capacitor together. The main solute plays a supporting role on the electrolyte performance and provides ions to repair the oxide film during operation. The additives may act to increase and improve the electrolyte properties. For example, to increase sparking voltage, to reduce leakage current, and to increase the service temperature range, etc. The additive has small proportion in the working electrolyte, but has remarkable effect of improving the performance of the electrolyte, and is an indispensable important component of the electrolyte. With the rapid development of aluminum electrolytic capacitor technology, in addition to increasing requirements on raw materials such as aluminum foil, rubber plugs, electrolytic paper and the like, stricter requirements are also put on the types and performances of electrolyte additives. The different solute solvent systems and additives work in combination differently. Proper matching can improve the electrolyte performance, otherwise, the electrolyte performance is negatively affected. At present, the traditional electrolyte mostly adopts linear carboxylate and a solvent system, and additives comprise phosphate, nitro compounds and the like, but the problems of low flash power, high vapor pressure, poor high-temperature stability and the like exist. In recent years, polyester polyols have been studied as additives that can improve the sparking voltage and thermal stability, but have reduced low temperature properties and lack functional modification. In the prior art, polyester polyol is mostly of a linear structure, and cannot be effectively adsorbed on the surface of an oxide film, so that the performance improvement is limited. In addition, high-end additives rely on importation and are costly. Therefore, a new electrolyte additive is needed to achieve a comprehensive performance breakthrough through material modification. Disclosure of Invention The invention aims to provide a liquid aluminum electrolytic capacitor, which solves the following technical problems: The existing liquid aluminum electrolytic capacitor has the problems of short service life at high temperature, low sparking voltage and poor low-temperature performance. The aim of the invention can be achieved by the following technical scheme: A liquid aluminum electrolytic capacitor made by the method of: sequentially overlapping and winding the anode foil, the first electrolytic paper, the cathode foil and the second electrolytic paper into a core package; carrying out impregnation electrolyte treatment on the core package, and obtaining a liquid aluminum electrolytic capacitor after the core package is put into a shell and packaged; the electrolyte at least comprises the following raw materials in parts by mass: 60-75 parts of N, N-dimethylformamide, 15-25 parts of ethylene glycol, 3-5 parts of boric acid, 1.5-3 parts of ammonium formate, 1-3 parts of silicon-boron modified polyethylene glycol adipate, 0.5-1.5 parts of triethylamine, 0.3-0.7 part of ammonium hypophosphite and 0.2-0.5 part of p-nitrobenzoic acid. The preparation method of the silicon-boron modified polyethylene glycol adipate at least comprises the following preparation steps: Mixing adipic acid, glycol and gamma-aminopropyl triethoxysilane triethyl borate, introducing nitrogen to perform a step heating reaction, closi