Aluminum electrolytic capacitor electrolytic capacitor. The properties of this aluminum oxide layer compared with tantalum pentoxide dielectric layer are given in the following table: After forming a dielectric oxide on the rough anode structures, a counter-electrode has to match the rough insulating oxide surface. This is provided by the electrolyte, which acts as the cathode electrode of an electrolytic capacitor. Electrolytes may be "non-solid" (wet, liquid) or "solid". Non-solid electrolytes, as a liquid medium that has an "ion conductivity" caused by moving ions, are relatively insensitive to voltage spikes or current surges. Solid electrolytes have an "electron conductivity", which makes solid electrolytic capacitors
Electrolytic capacitor are therefore smaller than aluminium electrolytic capacitors. In practice different safety margins to reach reliable components makes a comparison difficult. The anodically generated insulating oxide layer is destroyed if the polarity of the applied voltage changes. Electrolytic capacitors are based on the principle of a "plate capacitor" whose capacitance increases with larger electrode area A, higher dielectric permittivity ε, and thinner dielectric (d). The dielectric thickness of electrolytic capacitors is very small, in the range of nanometers per volt. On the other hand, the voltage strengths of these oxide layers are quite high. With this very thin dielectric oxide layer