Higher Capacitor performance: keep in Seal(I)

Nowadays, aluminum electrolytic capacitors are becoming more and more common in our daily life. New capacitors are gradually entering the market, such as supercapacitors and double-layer capacitors, EDLC, which will be used in electric vehicles (including electric vehicles, hybrid vehicles and electric buses), high-power applications and renewable energy applications. The defence and aerospace sectors, as well as various industrial applications.

However, aluminum electrolytic capacitors have a weakness: electrolyte loss is easy to occur throughout the life cycle. This is usually caused by imperfect terminal seals. A small amount of moisture permeates the imperfect seal, and over time accumulates gas inside the capacitor. Electrolyte loss leads to a continuous decline in performance, which requires the use of super capacitors or two capacitors, but if no electrolyte loss occurs, a single capacitor is sufficient. Slow and continuous evaporation of electrolyte can lead to up to 20% loss of capacity, which has a great impact on efficiency.

Polymer sealing is often used in capacitor terminals, which is one of the main inducements of electrolyte evaporation loss. Like all organic materials, polymers become fragile over long periods of time and cannot remain airtight. This aging process is not beneficial to aluminum electrolytic capacitors. Moisture seeps through an imperfect seal, evaporating the electrolyte and eventually leading to a significant reduction in the capacitance.