Top 5 Reasons to Use Ultracapacitors in Your Design!
Written by Greg Allen
Tuesday, 27 May 2008
In the past, most all devices we have used have used have had one energy supply. The engineers designing the device designed it to have too much energy or too much power at any given time. Now we see the ultracapacitor where you can leverage both energy and power and have high performance that cost less. There are many reasons to switch to using ultracapacitors.. here are 5:
High Efficiency - Ultracapacitors have a columbic efficiency that is greater than 99%. So little is lost during charge/discharge. Ultracaps have a low equivalent series resistance (ESR).which make them more efficient use of energy (less heating and less cooling for energy storage).
Temperature Range - Ultracapacitors do not rely on chemical reactions like a battery - so they can operate at a wide range of temperatures. Typically from 65 degrees Celsius to -40 degrees Celsius. This means excellent cold performance as a perfect fit for engine starting. When you put ultracaps with batteries, you can have a system that meets the energy requirements (battery) with the power requirements (ultracapacitor). A good example is that you can use it to start your engine and power lights and your stereo when the engine is off.
High Current - Since ultracapacitors are designed with very low equivalent series resistance (ESR) – they deliver and can absorb a high current. They can be quickly charged making them great for regenerative braking situations (like capturing the energy of a train an other quick charge/ quick release scenarios). There isn’t a battery made that can tolerate this charge/discharge rate.
Voltage Range - Since we are talking about capacitors, you are not confined to a narrow voltage range. If you are a designer, you only need to look at the voltage range of your system which is much wider than the narrow voltage required by your battery. With an ultracapacitor, to get a higher voltage, multiple cells are placed in a series which equate the total maximum voltage. A great thing is that you never have to worry about over discharging an ultracapacitor.
Long Life Cycle - The energy storage of an ultracapacitor is a highly reversible process. The process will move charge and ions only and does not make or break chemical bonds (like a battery). This process allows for hundreds of thousands of charge/discharge cycles without minimal change in your performance. This is perfect for something like a uninterruptible power supply (UPS) that may only charge/discharge fully a few times a year. Or another example is a hybrid electric vehicle that may be cycled frequently.
Ultracaps don't have the memory effects like batteries that we have so become accustomed to. An ultracapacitor will be smaller and maintain a much longer energy life while charging and discharging better than any lithium ion battery. Higher current.. and higher efficiency.
DID I SAY TOP 5??? I meant TOP 6!
6. Long Life- Once again.. since there are no chemical reactions like in a battery, the energy storage of an ultracapacior is a highly stable process which is capable of many years of continuous performance. Ultracapacitors can be installed for the life of the system not on a regular maintenance routine like a battery (costing time an money).
Make it Green!
Readers have left 6 comments.
"Ultracapacitors do not rely on chemical reactions like a battery - so they can operate at a wide range of temperatures. Typically from 65 degrees Celsius to 85 degrees Celsius."
I know that 1 degree Celsius is worth nine fifths of a degree Fahrenheit, but even so 20 degrees Celsius is not a very big range. :)
Sorry.. it was a mistype. It's fixed now. Thanks for the catch.
How can ultra caps be integrated into a PV system for my home? how do you control the voltage during discharge of the ultra cap?
How can ultra caps be integrated into a PV system for my home? how do you control the voltage during discharge of the ultra cap? — Jori
No.5 Use caps as replacememt for small batteries
I use Super caps (10X NessCap 2.3v 220F in 4.6v power-pak) to replace small batteries (AAA, AA) for devices that take 3 to 5 volts. The caps are expensive but worth it in this type of application. Since I can go through batteries with some devices (GPS, razor). I replaced (removed) the NI-CD's in my electric razor (18 year old Norelco) so I would never have to buy a NI-CD again. I never have to worry about leaking, dead or replacement (out in the woods - no store) batteries. I get much better value out of my power-pak when I run all devices from the single pack. Charging is from either solar or 12v car adapta-plug (4.5v setting).
How do they compare to conventional batteries in weight?