[Robert Murray-Smith] A World First - A 10 kiloFarad Capacitor (10,000 F) - made for Edison Power [O

edited November -1 in General
I wish to share the knowledge Robert Murray-Smith, a very knowledgeable chemist and open-source inventor shares with the world!

This home-made 10,000 farad capacitor (2.7votls!) he presents was made for a company called Edison Power - which is just crazy - it is slightly larger than half a ream of paper - so in capacitor terms tiny for the amount of power it can hold.

Finishing a long standing project on making a 1,700F supercapacitor [DIY & Opensourced!]

Here is the full Ultra Capacitor playlist


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    In the video the guy says the amount of energy stored in the 10,000F capacitor is 38,000 joules. A joule isn't much energy.

    By my calculations that is 0.01 kWh. The smaller Tesla battery is now 70KWH. He misses by a factor of 7000. So to match the tesla battery you need 7000 of his devices. Of course by the time you put all those things into a car you would probably have a weight much larger than the tesla battery pack. Interesting work but not ready for prime time.
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    Yada yada yada
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    The Duracell MN1400 (a non-rechargeable alkaline C cell battery) has a nominal voltage of 1.5v and capacity of 7,000mAh. This implies it stores (1.5 x 7 x 60 x 60) = 38,000 joules.

    That it folks. One advantage- Roberts Murray-Smiths capacitor can discharge in a split of a second instead of hours. Elon had question about "marriage" supercaps with batteries and he replied that they experiment with this type of setup. Result: "When you have 85Kw battery pack, super capacitors are useless".
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    I want to point out some benefits of supercapacitors that may or not be understood in this discussion:
    1. Cooling is not needed. Because of this one point, there are multiple benefits - overall efficiency improvement, less parts to fail (cost), better payload/vehicle weight, less fire hazard
    2. The life cycle count is in the millions, versus low thousands for batteries. Because of this the life cost of the vehicle is improved many times over.
    3. The power profile is much better - already stated, I know, but bears keeping in mind - this is a big deal for everything not just vehicles - think grid stability
    4. The most recent update from RMS/SunVault is a 1,000,000 F supercap. The voltage stabilizes near 2V (I think). The specimen is only 8 x 16 x .3 cm from what I can tell in the video. 1/2CV^2 is the equation for energy in a supercap; and while I recognize the real energy storage must be measured, not theorized, even if you took half of what the theoretical storage would be (0.56 kWh)he is still packing 0.277 kWh into something that when folded in half would be about the size of a cellophane wrapped slice of American cheese. This type of supercap is flexible. Batteries as they are today are not. By that energy density (over 7000 Wh/L), it would take a storage unit smaller than the size of a common rollaway bag to replace the 85kWh battery that now takes up much more volume.
    5. Supercaps based on graphene use some doping interstitials to be effective. However, most of their content is pure carbon (abundant and inexpensive). For that reason, they can be recycled or discarded without any hazardous material handling, unlike batteries.
    6. The main driver for all of this is cost. The company Robert Murray-Smith works for now, SunVault, is saying they can produce these energy storage devices for $100/kWh. Compare that to the PowerWall product at $350/kWh. This would have the affect of not just disrupting Tesla's/Panasonic's battery business, but the entire vehicle (EV and octane, natural gas, diesel, etc.) market, the power industry, etc. This is the upfront. The life cycle cost bears out even better, because there is very little degradation of supercaps over time. There is no chemical reaction taking place.

    Sorry to bloviate. I welcome discussion/rebuttal, but I just ask we maintain a mutual tone of respect and kindness. Thanks.
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    @joshuafausset, I don't have any doubt at all about all of the other points you brought up because capacitors have been known to be superior to batteries on most of those other features, but...

    #4 Seems outlandishly hard to believe because energy density of capacitors is really bad compared to batteries and since energy density is priority 1, 2, and 3 before any other factor for an electric vehicle, that's just why capacitors haven't been used. If they have achieved that level of energy density, that would be a jaw-dropping, staggering, revolutionary achievement--not just an improvement--so I remain skeptical of that one.
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    No one mentions the tendency of capacitors to rather quickly self-discharge. Much faster than Li-ion.

    "Keep that cord handy, and drive quickly to your next charging destination."
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    @joshuafausset Million Farads in that size would be insane. Verifiable sources for that? Because claim that high yells: FRAUD! SCAM! GET OUT OF THERE!
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    Well gentlemen, here is the latest from Robert's work.

    As you will notice the energy density is 375 Kw/kg. Very nice it will make the Kia or Golf etc go for at least 300 miles. It can recharge in a very short time too!

    I know that the volumetric density is not mentioned and that the number of cycles is too little. But from reading and watching they did mention that the cost of making this storage device is going to be around $40 Kw. Wow I would say. I hope that you Elon have the time to read this.

    We all know that Elon was going to do a PhD in capacitors. So I am sure that he is following the development of capacitors maybe more than I do. But please Elon comfort us and tell us that Tesla is safe.

    The way I see it is no matter what storage device will be used be them batteries or capacitors; these devices will need to be done some where. The Giga factory is the place and I suspect that we will need a few of these factories. But maybe Robert is so clever that he did this capacitor in such a way that we can do it at home with an inkjet printer. We still need to make a good car (motor inverter etc) and Tesla is doing a good job here.

    So all in all I am happy that we are entering a new ERA and oil is no longer needed. No more wars.

    Ah and even if the volumetric density is not ok for a car I am sure it is ok for home storage (solar and wind)
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    2... 3... 4...


    <b>Alaa:</b> Why do you keep using 'Kw' instead of 'kWh'...? There is a difference you see. One is completely incorrect. The other is an actual unit of measure.
  • edited November -1
    @ <b>greenmeresearch</b> (May 5, 2015)

    << This home-made 10,000 farad capacitor (2.7votls!) he presents was made for a company called Edison Power ... >>

    Both Sunvault and Edison Power seem to be fabrications of some sort.
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    It most definitely sounds like a scam.
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    Just prove the technology. All they need to do is go down to Cowboy Bob's used car lot, buy a clapped out Jetta and convert it. Or simply get an old go kart and put in an electric motor from Grainger. If it works, and the bean counters agree that it is cheap enough, then we have a revolutionary thing going on in the entire world of energy storage.

    Simply license it out. Fame and fortune would soon follow. Not to mention helping the entire world out.

    Saving it for some a start-up auto manufacturing idea is the very worst idea and makes the whole thing seem pretty sketchy.
  • edited November -1
    Red Sage ca us:

    I beg you to forgive me. You are right and I am wrong.
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    Are you happy with yourself now??? You made @Alaa cry!
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    I've also kissed the girls and made them cry...

    But my name isn't Georgie Porgie, nor Puddin' Pie!
  • edited November -1
    Well gentlemen I was thinking about the limited number of cycles that these capacitors have. They say more than 500 times. Well from a purest point a view infinity is more than 500. We all know that capacitors usually have a very high number of cycles so it was a bit strange to see them say >500!

    The other thing is the ESR. The ESR is too high for capacitors, and usually they mention the frequency at which you charge and discharge a capacitor to measure the ESR. In the link they do not mention that. It makes sense because the application will never need a charge and discharge at 100 Hz. So this is an indication that they are targeting the automotive industry with these devices.

    At any rate the 0.23 ohms that they mention is still high and if the voltage is 1.9 v then the maximum current that could flow in a short cir-cute is 1.9/0.23=8.26 amps! Very little if you ask me but if they are arranged in parallel and then in series to supply the voltage required to move the motor I suspect that these numbers will be ok. It was also nice of them to say that the short circuit will not damage the device. After all it is only 8.26 amps.

    So all in all every thing is fine; and the 500 cycles are also fine because if we assume that the car will have a 100 kWh pack then it will have a range of roughly 500 miles assuming a 200 watt consumption per mile. The weight of the pack will be (100 kWh / 375 Wh per kg) we get 266.66 kg. Very nice I would say and I would not mind having double that weight to increase the range. Remember that the pack of the model S weighs much more than that. So if we take the 500 miles range and the 500 cycles then we have 250,000 miles before we need to change the pack. And if the price of the pack is $4000 then I would say a very good deal indeed.

    So it looks to me that Sunvault is targeting Tesla in particular since no other makes an EV that goes more than 200 miles except Tesla.

    So when we read that Tesla will reduce the price of the batteries by 70%

    then every thing fits! And this will help speed up the model 3. At least I hope so.

    Any thoughts anyone?
  • edited November -1
    <b>Alaa:</b> Yadda, yadda, yadda... You always seem to leave out crucial information, just like all the rest. Try giving us the volume of this 100 kWh, 266.66 kg capacitor, eh? Why are you certain they will weigh so little? What is the size and shape of the capacitor? How will they be charged? Who will make them? Where is the demonstration version? Why are you so apt to want something that must be replaced every 250,000 miles, when it's already been demonstrated that the current battery technology will last three times that long, and future versions will last even longer?
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