A
capacitor assembly for use in
high voltage and high temperature environments is provided. More particularly, the
capacitor assembly includes a
solid electrolytic capacitor element containing an
anode body, a
dielectric overlying the
anode, and a
solid electrolyte overlying the
dielectric. To help facilitate the use of the
capacitor assembly in
high voltage applications, it is generally desired that the
solid electrolyte is formed from a dispersion of preformed
conductive polymer particles. In this manner, the
electrolyte may remain generally free of
high energy radicals (e.g., Fe2+ or Fe3+ ions) that can lead to
dielectric degradation, particularly at relatively high voltages (e.g., above about 60 volts). Furthermore, to help protect the stability of the solid electrolyte at high temperatures, the capacitor element is enclosed and hermetically sealed within a housing in the presence of a
gaseous atmosphere that contains an
inert gas. It is believed that the housing and
inert gas
atmosphere are capable of limiting the amount of
oxygen and
moisture supplied to the
conductive polymer of the capacitor. In this manner, the solid electrolyte is less likely to undergo a reaction in high temperature environments, thus increasing the
thermal stability of the capacitor assembly. In addition to functioning well in both
high voltage and high temperature environments, the capacitor assembly of the present invention may also exhibit a high
volumetric efficiency.