Saisri_Main seminar-1
Transcript of Saisri_Main seminar-1
Ultra capacitors (Super capacitors)
SAISRI.R16031DA708
Nano Electronics & Photonics
ABSTRACT• Super capacitor also known as electric double-layer
capacitor (EDLC), super condenser.• Compared to conventional electrolytic capacitors the energy
density is typically on the order of hundreds of times greater than the comparison with conventional batteries like fuel cells.
• In this article the use of super capacitors likes hybrid power supply for various applications is presented.
• The main application is in the field of automation.• Carbon Nano tubes,Graphene,Carbon Aerogel are mainly
used to develope super capacitor using Nano technology.
Introduction• Capacitor• Super Capacitor• Types of Super Capacitor• Construction and Working of Super Capacitor• Super Capacitor Vs Normal Capacitors• Advantages & Disadvantages• What are the Technologies used• Applications• Conclusion• Reference
Capacitors• In general, capacitor is a device to store the
charge in an electric circuit. • Basically, a capacitor is made up of two
conductors separated by an insulator called dielectric.
• The dielectric can be made of paper, plastic, mica, ceramic, glass, a vacuum or nearly any other nonconductive material.
Super Capacitors
• Super capacitors can be defined as a energy storage device that stores energy electrostatically by polarizing an electrolytic solution.
• Super capacitors are also known as double-layer capacitors or Ultra capacitors.
Supercapacitor Types
Supercapacitor Types• Double-layer capacitors – with activated carbon electrodes or
derivate with much higher electrostatic double-layer capacitance than electrochemical pseudo capacitance.
• Pseudocapacitors – with transition metal oxide or conducting polymer electrodes with a high amount of electrochemical pseudo capacitance.
• Hybrid capacitors – capacitors with asymmetric electrodes one of which exhibits mostly electrostatic and the other mostly electrochemical capacitance, such as lithium-ion capacitors.
Construction
• Ultracapacitor consist of a porous electrode
• Electrolyte• A current collector
(metal plates)• A membrane, which
separates, positive and negative plated is called separator
Working
Diagram shows the formation of double layer
c
Super capacitors Vs. Rechargeable Batteries
Super Capacitors:• Higher power density • Much faster charge and
discharge rate• Environmentally friendly • Extremely low internal
resistance or ESR • High efficiency (97-98%)• Over a million charge-
discharge cycles
Rechargeable Batteries: • Have higher energy density • Typically 200–1000 charge-
discharge cycles• Contain highly reactive and
hazardous chemicals • Negatively effected by low
temperatures
Advantages• Long life: It works for large number of cycle without wear and
aging.
• Rapid charging: it takes a second to charge completely.
• Low cost: it is less expensive as compared to electrochemical battery.
• High power storage: It stores huge amount of energy in a small volume.
• Faster release: Release the energy much faster than battery.
Disadvantages• They have Low energy density
• Individual cell shows low voltage
• Not all the energy can be utilized during discharge
• They have high self-discharge as compared to battery.
• Voltage balancing is required when more than three capacitors are connected in series.
Development in Super capacitor using Nano technology
• Nano technology is used for expanding the possibilities and practically of an alternative energy future.
• Nano technology uses for producing highly efficient and effective nano technology are showing more effective future.
• Carbon Nano tubes, carbon aerogels are used for super capacitor plates or electrodes.
• Sodium perchlorate or lithium are used as electrolytes.• Polyacrylonitrile is used as a separator which has thickness
of (0.3-0.8nm).• Aluminum as a packing component.
Carbon Nanotubes
Approximately 1/50,000th the width of a human hair
Strongest and stiffest material on earth (>300 X Steal)
Low density Semiconductor
Carbon Aerogel
• Composed of nanometer sized particles covalently bonded together
• High porosity (>50% under 100 nm)
• Large surface area (400–1000 m²/g)
- Aerogel is a low-density solid derived from gel that has had the liquid component replaced with a gas.
Applications• They are used in electronic applications such as
cellular electronics, power conditioning, uninterruptible power supplies (UPS).
• They are used in industrial lasers, medical equipment.
• They are used in electric vehicle and for load leveling to extend the life of batteries.
• They are used in wireless communication system for uninterrupted service.
Different styles of supercapacitors
Flat style used for mobile
components
Typical knob capacitor for PCB
mounting used for memory backup
Radial style of a (lithium-ion
capacitor) for PCB mounting
used for industrial
applications
Conclusion
• Ultracapacitors (Supercapacitors) offer a promising alternative approach to meeting the increasing power demands of energy storage systems and electronic devices.
• With their high power density, ability to perform in extreme temperatures, and millions of charge-recharge cycle capabilities, supercapacitors can increase circuit performance and prolong the life of batteries.
THANK YOU
References
• 1.http://www.tecategroup.com/ultracapacitors-supercapacitors/ultracapacitor-FAQ.php#What_is_end_of_life_and_failure_mode_for_an_ultracapacitor
• 2. http://batteryuniversity.com/learn/article/whats_the_best_battery