Aerogel capacitors

[carlmart]

Has anyone heard anything on this Powerstor Aerogel Supercapacitor sold by Mouser?

http://www.mouser.com//index.cfm?handler=fra_pdfset&pdffile=284

Today I was searching Mouser's Web catalog and found these. They are expensive, made with carbon foam and have low ESR.

Perhaps an alternative to BGs?...


Carlos

 

[tiroth]

Nice find. Those are some huge caps! However, I'm not sure these will be better than other supercaps.

Although PowerStor aerogel supercapacitors have very
low resistance in comparison to other supercapacitors,
they do have higher resistance than aluminum
electrolytic capacitors and are more susceptible to
internal heat generation when exposed to ripple
current. Heat generation leads to electrolyte
decomposition, gas generation, increased ESR and
reduced lifetime. In order to ensure long lifetime,
the maximum ripple current recommended should not
increase the surface temperature of the supercapacitor
by more than 3°C.

Product info:
http://www.cooperet.com/products_supercapacitors.asp

 

[Elkaid]

Is it me or it's just a typo ?

The capacitance for the AeroGel capacitors is stated in Farads (F) and not in microFarads (uF)

I'm quite surprised to find 50 farads capacitor under 20$ each 🙂

Just wondering 🙂

 

[FunkyStu]

Just for info the values are correct but notice the very low operating voltages.

The aerogel stuff is pretty funky though ! Check out this page.

http://stardust.jpl.nasa.gov/tech/aerogel.html

 

[SY]

It's you. That's no typo.

 

[Steve Eddy]

Is it me or it's just a typo ?

The capacitance for the AeroGel capacitors is stated in Farads (F) and not in microFarads (uF)

I'm quite surprised to find 50 farads capacitor under 20$ each 🙂

Nope, it's not a typo. Though they're not your typical aluminum electrolytic type capacitors. The technology used allows for a huge amount of surface area within a very small package compared to normal electrolytics. Various kinds of "super caps" have been around for years. Just that they typically weren't suitable for applications other than memory backup due to their high internal resistance.

These aerogel caps have a much lower resistance than the older "super caps" but they're still only rated at 2.5 volts so you'd have to string them together in series to be able to handle higher voltages which reduces capacitance and the internal resistances add.

Ultimately you'd need to series a bunch together, and then parallel a bunch of those together in order to get suitable voltage handling and internal resistance. Then the cost isn't so cheap. 🙂

se

 

[Sawzall]

not a typo

Farads. Strange concept to grasp since back in the olden days, we used wierd examples of what a farad actually was - copper plates one mile apart and such.

Now every kid with a stereo in his car is getting one of these "stiffening" caps put in. That his cheap amp cannot really benefit from it is another story.

 

[tomtt]

seems they also have 2500f caps as well

 

[Steve Eddy]

seems they also have 2500f caps as well

Yup. But of course only 2.5 volts. 🙂

These kinds of caps aren't particularly new technology. <a href="http://www.maxwell.com">Maxwell</a> has been making them for some years now (they call 'em BoostCaps now, but they used to be called PowerCache).

Though it's nice to see the same type of capacitors readily available through stocking distributors like Mouser.

Here's a Maxwell module (made using multiple seriesed/paralleled caps) that will give you 145 FARAD of capacitance at 42 volts. 🙂

<a href="http://www.maxwell.com/ultracapacitors/products/BMOD0115.html">http://www.maxwell.com/ultracapacitors/products/BMOD0115.html</a>

se

 

[joe carrow]

I was just bowsing Digi-Key for parts today, and saw a 50 farad capacitor for $26. That makes me want to ask two questions-

First, isn't it possible to wire capacitors in series/parallel to get a large capacitance with a higher tolerable voltage?

Second, has anybody used these, or seen them used, on a cool project?

Joe

 

[thomas997]

How do these compare to batteries?

For example a rechargable AA is about 1700mah at 1.2V

Is that comparable to farads?



thanks

 

[pmkap]

As I post, only 81 are available...
http://www.allelectronics.com/cgi-bin/category.cgi?category=140910&item=CBC-131&type=store
FWIW

 

[GRollins]

Yes, capacitors can be wired in series in order to increase their voltage rating. Unfortunately, you then find that the capacitance is decreasing.
It's a good idea to use a resistive voltage divider to make sure that the voltage doesn't wander.

Grey

 

[jacco vermeulen]

For example a rechargable AA is about 1700mah at 1.2V

1 F = 1 A * S / V
Do the calculation yourself.

Two examples :

the battery of your car can light the front and head lights for 4,
5 hours. Say 50 watts for 14400 seconds, thats well over 700 kJ.

200 submarine battery cells of 1.3 Volts are able to power a submarine for numerous days, at 25 Knots submerged !

A 10.000 uF/ 50 volt capacitor has : 0.01 * ( 50 * 50 ) /2 = 12.5 J
stored energy.