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Electrochemical Supercapacitors for Energy Storage and Delivery
ES application areas include power electronics, memory protection, battery
enhancement, portable energy sources, power quality improvement, adjustable speed drives (ASDs), high power actuators, hybrid electric vehicles,
renewable and off-peak energy storage, and military and aerospace applications. All these application areas will be discussed in this chapter.
8.2 Power Electronics
Modern portable electronics devices have been used in many industrial,
commercial, residential, aerospace, and military applications. Recently, due
to the high demand for energy conservation, power electronics are gaining
great attention in the area of energy efficiency.
The systems of most power electronics need energy storage devices to
provide energy back-up and decoupling between power conversion stages.
Due to their low cost, the most common storage devices are conventional
electrolytic capacitors and batteries, but they have drawbacks related to
size, performance, and cycle life. Several new energy storage technologies
now available appear to be promising options to traditional energy storage
devices. Electrochemical supercapacitors (ESs) appear to be outstanding
options for applications, particularly in areas requiring high power densities, fast transient responses, and reduced volume.
As discussed in previous chapters, ESs are new energy storage devices
with excellent potential for portable applications such as power electronics systems due to their high capacitance values ranging from 1 to 2700 F,
equivalent series resistance typically 10 times lower than resistances of conventional capacitors, and long cycle lives. The large capacitances of ESs make
them suitable for backup energy storage in power electronics systems requiring reduced size. In the following sections, more applications of power electronics will be discussed.
8.3 Memory Protection
For many decades, several battery systems including lithium types have
been used in memory protection or back-up power applications. However,
batteries are not always the ideal solution. Some batteries need sophisticated
recharging circuits; otherwise they can undergo temperature runaways and
can explode. Due to limited cycle lives, they must be replaced relatively frequently and need to go through a series of conditioning steps before entering
service. Finally, when you really need them, they may not last long enough to
Electrochemical Supercapacitors for Energy Storage and Delivery
ES application areas include power electronics, memory protection, battery
enhancement, portable energy sources, power quality improvement, adjustable speed drives (ASDs), high power actuators, hybrid electric vehicles,
renewable and off-peak energy storage, and military and aerospace applications. All these application areas will be discussed in this chapter.
8.2 Power Electronics
Modern portable electronics devices have been used in many industrial,
commercial, residential, aerospace, and military applications. Recently, due
to the high demand for energy conservation, power electronics are gaining
great attention in the area of energy efficiency.
The systems of most power electronics need energy storage devices to
provide energy back-up and decoupling between power conversion stages.
Due to their low cost, the most common storage devices are conventional
electrolytic capacitors and batteries, but they have drawbacks related to
size, performance, and cycle life. Several new energy storage technologies
now available appear to be promising options to traditional energy storage
devices. Electrochemical supercapacitors (ESs) appear to be outstanding
options for applications, particularly in areas requiring high power densities, fast transient responses, and reduced volume.
As discussed in previous chapters, ESs are new energy storage devices
with excellent potential for portable applications such as power electronics systems due to their high capacitance values ranging from 1 to 2700 F,
equivalent series resistance typically 10 times lower than resistances of conventional capacitors, and long cycle lives. The large capacitances of ESs make
them suitable for backup energy storage in power electronics systems requiring reduced size. In the following sections, more applications of power electronics will be discussed.
8.3 Memory Protection
For many decades, several battery systems including lithium types have
been used in memory protection or back-up power applications. However,
batteries are not always the ideal solution. Some batteries need sophisticated
recharging circuits; otherwise they can undergo temperature runaways and
can explode. Due to limited cycle lives, they must be replaced relatively frequently and need to go through a series of conditioning steps before entering
service. Finally, when you really need them, they may not last long enough to