Among the basic components utilized in electronics there is the capacitor; the related equation that describes how this component works is as follows:
In the equation above, C represents the capacitance that in most applications is a constant and independent of time. The independent variable, Ic(t), is the current charging the capacitor at the instant t and Vc(t) is the voltage that appears across the capacitor at the instant t due to the electric current that brings electric charges to the terminals of the capacitor (see Figure 1):
The charging of a capacitor through an RC series circuit
Equation 1 reveals that if the charging rate of the voltage varying current is kept constant, a high value of C guarantees a high peak current from the capacitor, hence for an integrated capacitor, as part of an IC, it is desirable to have a value of capacitance as high as possible.
This consideration underlines the importance of supercapacitors as key components for electronic circuits: graphene is an optimal building material for such capacitors (see Figure 2).
Graphene supercapacitors are a very promising solution for many applications requiring high energy storage capability and increased energy autonomy:
“Due to the lightweight dimensions of graphene based supercapacitors and the minimal cost of production coupled with graphene’s elastic properties and inherit mechanical strength, we will almost certainly see technology within the next five to ten years incorporating these supercapacitors. Also, with increased development in terms of energy storage limits for supercapacitors in general, graphene-based or hybrid supercapacitors will eventually be utilized in a number of different applications. Vehicles that utilize supercapacitors are already prevalent in our society. One Chinese company is currently manufacturing buses that incorporate supercapacitor energy recovery systems, such as those used on Formula 1 cars, to store energy when braking and then converting that energy to power the vehicle until the next stop. Additionally, we will at some point in the next few years begin to see mobile telephones and other mobile electronic devices being powered by supercapacitors as not only can they be charged at a much higher rate than current lithium-ion batteries, but they also have the potential to last for a vastly greater length of time.” (Source: graphenea)
Furthermore the mechanical and electrical properties of graphene make it an ideal substrate to produce supercapacitors for wearable electronics (see Figure 3):
“A team of researchers at Nanyang Technological University in Singapore has developed a flexible supercapacitor using ribbons of graphene, naming it a 'micro-supercapacitor'”
(Source: EETimes Europe)
Graphene material promises to become an exceptional solution for realizing supercapacitors in wearable applications and printed integrated circuits.
What do you think about this type of material? Do you think it offers a wide range of options for electronics technology?