What is a typical characteristic of a capacitor?

Capacitance is a typical characteristic of a capacitor. And is generally expressed by the following formula. As the above equation shows, capacitance is proportional to the surface area of the electrode and dielectric constant of the dielectric and inversely proportional to the dielectric thickness.

What is the difference between nickel-based batteries and electrochemical capacitors?

The fundamental difference between nickel-based batteries and electrochemical capacitors is that the redox reactions in batteries occur in the bulk phase; while the energy stored in supercapacitors is mainly due to the surface-involved processes. This disparity leads to the different theoretical limits of the stored energy.

Can nickel electrodes be used for RF capacitors?

The plot shows that the nickel wire's resistance starts increasing above 10MHz, while the copper wire's resistance increase is negligible in the GHz frequency range. Therefore, nickel electrodes are not preferred for RF capacitors. In some RF capacitors, PdAg may be used, which does provide good ESR at higher frequencies.

What is the capacitance of nickel-based supercapacitors?

A graphical overview of numerous papers published on the nickel-based supercapacitors is shown in Fig. 4. The data are retrieved from the Google scholar database. Most of these papers demonstrate that the achievable capacitance is around 500–2500 F g −1 (250–1250 C g −1).

Is a capacitor a condenser?

Although the term capacitor is common in most parts of the world, in Japan it's often referred to as a condenser. Capacitors come in various types, but the basic structure consists of an insulator (dielectric) sandwiched between electrodes, capable of storing charge when a voltage is applied.

Which electrolyte has higher capacitance – nickel oxide or nickel hydroxide?

The former has higher capacitance due to the higher oxidation state of nickel. However, the former is not stable and can be easily transformed into the latter when alkaline electrolytes are used. The commonly used electrolytes for nickel oxide and nickel hydroxide are aqueous alkali solutions, such as KOH.