Electrolyte solution for electrolytic capacitor, and electrolytic capacitor

Abstract

Provided is an electrolytic solution for an electrolytic capacitor, which is capable of suppressing expansion of a housing container even during reflow soldering. The electrolytic solution for an electrolytic capacitor is characterized in that: the electrolytic solution for an electrolytic capacitor comprises a capacitor element having a positive electrode foil having a dielectric oxide film layer on the surface thereof, a negative electrode foil, and a solid electrolyte layer, and an electrolytic solution impregnated into the capacitor element inside a housing container; the electrolytic solution contains an organic carboxylic acid having a hydroxyl group, a boron compound, and a solvent, the content of the boron compound being 0.6 mol or more with respect to 1 mol of the organic carboxylic acid having a hydroxyl group, the solvent containing a protic organic solvent, and the content of the boron compound being 1 mol or more when the electrolytic capacitor is exposed to a high temperature of 250 DEG C or more. A pressure increase in the outer shell container can be suppressed.

Description

technical field [0001] The present invention relates to an electrolytic solution for an electrolytic capacitor capable of suppressing expansion of a case container even when exposed to a high-temperature atmosphere in a reflow process or the like, and an electrolytic capacitor using the electrolytic solution. Background technique [0002] In recent years, in audio-visual (AV) equipment, in-vehicle electrical equipment, and the like, expectations for higher reliability have been increasing, and electrolytic capacitors used in these have also been required to be small, large-capacity, and high-frequency equivalent series resistance ( Hereinafter, it is also referred to as ESR) and other properties. [0003] In particular, as the frequency of electronic equipment increases, electrolytic capacitors are also required to be large-capacity electrolytic capacitors having excellent ESR characteristics in a high-frequency region. Recently, in order to reduce the ESR in such a high-fr...

AI Technical Summary

Problems solved by technology

[0007] In the reflow soldering process at such a high temperature, the following phenomenon is observed: the pressure inside the case container increases due to the gas generated from the electrolyte in the electrolytic capacitor, causing expansion of the case container, such as an increase in the height dimension value of the electrolytic capacitor

In this case, in addition to failures occurring when the electrolytic capacitor mounted on the substrate is mounted on the device, the characteristics of the electrolytic capacitor itself may also be degraded, and its reliability may also be impaired (see Patent Documents 4 and 5).

Images