I realized my explanation of how these work was vague and poorly worded, sorry! Graphene-based supercaps are a form of electrostatic double-layer capacitors (EDLCs). Charge is stored at the interface between the electrode and electrolyte via electrostatic attraction when charged. Due to the small charge separation EDLCs can charge and discharge very quickly, and the extreme surface area of graphene foam gives a large interface with the electrolyte to improve overall capacitance. That's why the "perimeter" of interdigitated electrodes is important, because more exposed perimeter == more interface opposing the other electrode to accumulate charge.
What goes into selection of optimal electrolyte? What gives kapton tape this property of UV -> graphene? Could you estimate your capacitance economy? Like capacitance per area, volume, dollar, time, etc?
One other point on you're value measurements... It is not uncommon for capacitors to be manufactured under "tolerance" of 20% or more, so the meter might not be as inaccurate as it looks.
Your capacitance meter is likely more accurate than you realize; most commercial capacitors have a fairly wide tolerance from their stated value. Manufacturers data sheets should list the tolerance for each type the produce.
Agreed. One of the caps he tested looked like it was rather old (the 5uF unit). First, if it actually was rated 5uF, it really is old, because anything made after say, 1975 would likely have been a 4.7uF, not a 5uF unit. Anyway, old electrolytic caps tend to become leaky, and leaky caps often read high on capacitance checkers, even though their true capacitance is falling.
@@Gwallacec2 btw a quantum leap is extremely small. I mean I guess from the perspective of virtual particles it's extremely large, but a quantum leap is like between electron bands Then again scale becomes a very strange thing to consider eventually so I'll stop there.
It would be amazing to see RUclipsrs start a license free movement, I was just watching one guy create spider silk using genetically modified yeast and released the gene sequences he developed under an MIT license. Absolutely amazing, his next step was to actually have the yeast absorb graphine and/or carbon nanotubes to bond them in the silk to make it stronger.
I agree! It's pretty amazing what some of the minds on YT are capable of :) IIRC that was Thought Emporium.... he does some really fantastic work. One of my goals is to help spread knowledge of these interesting papers that are just buried in archives. Would be neat to see what we could accomplish as a group on YT sharing and developing different techniques that would normally end up in a paper or patent.. There are other interesting developments too, like Joe Barnard (BPS.space) working on launching suborbital rockets, etc. I'm happy to see YT being more than _just_ entertainment.
yep, capacitance meters can show a completely irrelevant reading if you just connect a slightly weird resistor-like thing to it... because from the video, i remained unconvinced that the device can actually store some energy.
@@victortitov1740 it works... my group works on this and other things in the lab (a little fancier, granted, but the principle is the same). That being said, I would have cycled it with a decent sourcemeter, then again, me, laser physicist lab, him, at home ... so.
@@randfee I am currently working on an electrostatic adhesion gripper. They require an input voltage between 1-6kV, so we need materials with high dielectric strength. At the moment we are ordering flexible PCBs with the interdigitated pattern and the space between the electrodes is limited by the dielectric strength of the adhesive. Would you be able to produce them with this method and what material would you use to cover the electrodes?
Welp, this is one of those treats of RUclips: An easy insta-subscribe with a new underappreciated channel. I look forward to watching your channel eclipse 100k subscribers in the next 6 months.
Your point about reaching a level of technology in a society where we can do pretty serious testing and innovation in our garages with off-the-shelf components is spot on… This is the future I ordered! Liked and subscribed! 😎👍🏼
every school need to have machine shops and maker spaces and every community needs to have at least one guild hall of sorts where crafts men and women can ply there craft and find young apprentices to share there knowledge with.
I wanna go to the kind of party where people demonstrate shit like this to each other. Party tricks where I'm from are usually something like someone opening a beer bottle with their eyebrow.
I actually have a friendly competition where my friends and I compete to create the coolest mechanical thing based on a theme. At the end of every other month we get together and show it off. You should join us! 😂
This capacitor seems like it could be useful as the flexure part of a homemade MEMS scale strain gauge, pressure or temperature sensor. Guys like me who are only hobbyists can't afford off the shelf devices just for the hell of it so making them is the only way to go. Lol
The bed heaters on my 3D printers typically have kapton covering them. They also suffer from being inconsistent and take a long time to come up to temperature with DC power (less so with the AC bed heaters), with less heat near the outer edges. If the kapton covering them were the actual heat source then I imagine it would perform MUCH better. :)
I immediately thought about the same thing. Aluminum is often used to spread the heat from the wires of a heater. Lot of the heat is lost to the backside of the plate. So what if you had a glass bed, completely covered with kapton tape and a standard PEI sticker on top of that. Glass is more rigid than aluminium, has lower density, is a fairly poor conductor of heat and even cheap glass sheets are usually flatter than aluminum. So one can have a lighter, more rigid and flatter bed, reduce losses from the backside and get a more uniform heating. Manufacturing this should be very easy too. Just apply kapton tape to the glass, treat it with a laser, run two pieces of copper foil on the sides for power, then apply PEI sticker on top. Or, perhaps a magnetic sticker to enable the use of removable flex sheets.
@@anttiandreimann8456 you'd also have to figure out where to shove the sensor to feed data back to the controller, and hope your PID tuning algorithm works properly. That said, insulation layer, kapton, electrodes and thermistor, then print bed should work really well and keep the heat directed upwards.
@@anttiandreimann8456 You could make the bed heater using the printer itself. Just mount the laser to the print head and run it uniformly over the kapton.
@@AlexanderTzalumen to try it out crudely there's a simpler solution, since the resistance of the "heating mat" shouldn't vary too much with the temperature swings (at max up to ~100°C of swing from ambient, for general 3D printing with "normal" materials) you could even characterize it measuring the temperature with a thermocouple vs PWM percentage of current, and then control it just by using a look up table and not even need a PID controller, as a certain amount of PWM controlled current should provide the same temperature consistently. Although thermal imaging would be necessary to ensure the current is not traveling in just a straight line or area of the mat (think skin-effect) as opposed to through the whole mat, because PWM-ing creates a lot of high frequency harmonics which may (or may not) induce this effect. Might give this a try one day if I get myself a laser, hope someone beats me to it because it sounds promising IMHO
@@markopesevski perhaps, but the marlin firmware used in the majority of hobbiest and consumer 3d printers all use PID controllers for their heating elements, partially for the initial temperature ramp, and also for maintaining temp stability against the various sources of heat loss (radiant losses, ambient air currents, part cooling fans, moving build plate, etc). For a heated build plate, inconsistant temperature can lead to 1st layer delamination, which will cause the print to shift, warp, or fully detach.
The reason for the high values could also be leakage current. Especially on cheap meters, leaky caps can lead to much higher readings than the actual capacitance.
Really good presentation on this... you talk so naturally with no hint of "I'm reading a script" and no "uuum" or "aah" either. Nice smooth editing too.
Just waiting for the youtube algorithm to bless this channel. Great work as usual, I'm using your metallic microlattice video for one of my projects right now.
@@BreakingTaps Played around with this graphene concept last weekend, turns out it works really great with the 10um co2 lasers, which is mighty convenient. Also turned much more black (vantablack?) than yours. Anyways, do you have a discord server or something? It would be neat to hang around, as I and a few friends are all doing similar stuff as you
@Wid Lay Awesome, glad to hear it! The first LIG papers were done on CO2 iirc, and there are some neat followup papers where they perform multiple passes to turn amorphous carbon into LIG (which isn't possible with shorter wavelengths like mine). Was used to make supercaps on coconuts and potatos as demonstrations :) I wonder if that's why yours was blacker? The literature shows that LIG is a big mess of graphene + amorphous carbon + fullerenes + tubes, so I wonder if the CO2 does a better job of converting some of the non-graphene into graphene? Dunno, but interesting result! No discord at the moment, but I was just thinking it'd be fun to have a place to gather folks working on similar stuff. Lemme set one up and I'll give you a ping!
Great research and presentation! The applications for this technique are huge! I'm an electronics engineer. And I think there's a possible fault on the capacitance metering. Multimeters presume you are measuring a capacitor, but electrodes in a acid medium will make a resistor(or RCL equivalent circuit), also may be electro-chemical reactions going on. There is no insulation on your device and electrons are flowing between terminals. It will probably self discharge almost instantly. To measure a capacitor precisely you first need to charge it, disconnect from source, than connect it to a load. Integrate the power it produced and you will have the energy it is able to store.
Ah interesting, does that apply when using a dedicated "capacitance meter"? I had assumed/hoped it had internal circuitry to power the cap to some degree and test it's leakage or something? This is the device I have: www.newark.com/general-tools/cap1500/capacitance-meter-digital-200pf/dp/59P4162 I did find that it self-discharged very quickly just sitting on the bench, and made even worse when poking it with a multimeter :) I'll see about setting up some kind of circuit as you suggest to test it. Thanks for the help! Electronics is definitely not my forte, very much a newbie still :)
@@BreakingTaps Hard to tell what process it uses to measure. But I think you don't have a capacitor(yet). You need an insulating medium between electrodes. For example electrolytic capacitors use aluminum oxide. In a capacitor electrons can't flow between terminals, there should be an insulation, where an electric field will be created to store enery.
@Eduardo Schoenknecht So big grain of salt due to my general ignorance, but my understanding from the literature is that these types of supercaps operate a bit differently. When charged, a helmholtz double layer is formed symmetrically on the electrodes using the ions in the electrolyte (graphene + | - electrolyte + | - graphene), so there isn't actually a dielectric in play here. Just ions associating / disassociating with the graphene at the interface between liquid and solid. In theory, based on my reading, but as I said I could have that incorrect :)
@@BreakingTaps you are right. And I don't have knowledge on super capacitors chemistry. But I think a special electrolyte is needed, regular diluted sulfuric acid will just conduct electricity.
Roger, thanks for the help! Will do some more reading on my end. I'm itching to see if I can scale this thing up, so might be able to make a more robust v2 at the same time :)
A note on the capacitance meter: electrolytic caps tend to have a very generous tolerance range, skewed up, since for the most part they're used with rectifying circuits for their relatively high capacity. There's a possibility for the real capacitance value to be closer to the meter readings than to the value on the label.
I've seen this editing style on quite a few channels lately. I'm guessing there is some popular videography instructional video out there that was promoting it.
@@BreakingTaps second camera is a nice touch, you could always just turn towards it, would be nice if you wanna add some extra info or something, like an aside in theatre....or malcolm in the middle haha
or the tangent cam, for when you go to explain something that is a bit off topic or complementary, but please do keep looking at us. tv show style makes me want to switch channels...
capacitance reading may be off in this case due to high leakage resistances, you need some type of rlc meter to determine simultaneously Parallel, series resistances AND capacitance. Parallel Resistance is responsible for leakage currents -determines self discharge speed actually, while series resistance is like a series connected resistor - limits the current and has other detrimental effects. But anyways with some clever experimentation I think you can figure out all of them. nice job.
Incredibly impressive project! Now I want to go order a laser from my printer and make use of the big roll of Kapton I've got. =] Great quality of shots, editing, and sound too. You put out a high quality video sir!
I keep seeing all these hype videos about super tech this and super magic that, but until it can directly improve my life it's nothing more than vaporware.
A kapton heater based electric countertop skillet sounds awesome. My current one has a very obvious hot ring where the wire heating element is. Or a kapton toaster. I assume it's near 100% efficient at turning the electricity into heat right?
This channel is one of my favorites actually, really awesome content. And that laser induced graphene are so versatile that a lot of technological applications can be made with that. Thanks to show us that amazing technique.
Great project! I'd be interested to see the leakage current and how long the capacitors will hold voltage with no external connections. Leakage current could also influence the readings from your multimeter, so this is something to watch out for.
Forgive the newbie question: I should be able to test this with just an oscilloscope right? Charge up, measure the discharge for a given period of time and then work out the resistance / leakage current from that?
A crude but portable way to check capacitor condition is to put a multimeter across the terminals and see what the resistance stabilises to. Ideally it should be infinite, but you know a motor start capacitor has definitely failed when it has a resistance under a few hundred ohms :). My understanding of the way most multimeters measure capacitance is they time how long it takes for the capacitance to reach a certain voltage from 0v with a known constant current, so any leakage resistance decreases the amount of current charging the capacitor and makes it appear larger in value than it actually is. I have also used an LC meter that seems to use some form of oscillation to measure capacitance and this seems a bit less sensitive, but can still do weird things with high leakage currents.
One important test for your capacitance meter -- put a resistor across it, no capacitance. Does it still try to produce a reading? If so, you need to be cautious about taking the measurements too seriously. Try also measuring DC resistance of the assembled graphene devices. WIth capacitance, the reading will start low and climb, but see if it tops out at some level or rises to effectively infinity (== good capacitor!)
Just found your channel today: love the videos, the level of detail, and pace. I'd been searching an Applied Science like channel and your's is a great addition to my subs. Thanks :)
Yeah probably, in which case who knows what this cheapo meter would read. This setup has barely any surface area and it's not really different from a printed metal pattern from what I can tell.
Awesome stuff man, really appreciate it ....thanks for the informative content, please share the specs of the laser, if possible the exact item link would be really helpful. Thanks.
I'm really interested in possibly using this method to build custom caps for rc planes. I'm curious about what you did with the contacts to allow current flow without melting the tape or having any issues. Is there a conductive glue that would work well for this?
Making good contact is unfortunately rather hard. I used copper tape, pressed mechanically against the LIG (that's what the allen keys and clamps are used for in the heating demonstration). A lot of academic papers use silver epoxy.
I bet you could use a fractal type pattern to maximize the area the graphine. I've seen PCB antennas that exploit this and I wonder if it would work in this case.
If you could make small enough laser lines, then you could make safety eye glass heaters that would defrost safety glasses (or any glasses, goggles) just like car window defrosters.
HEATED FDM PRINTER BED! Already flexible, stick it to a steel plate and now the heater itself is *above* any magnets you may be using. Were you running your laser at full power for this, or did you have it dialed down at all? If I can reproduce this on the Glowforge, I'll be pretty happy.
Ooh, I like that! That's a good idea, I wonder how large you can scale these up. I only tested smallish samples, and I dont think I saw any papers that did a big sample (usually only a few inches square). If you try, I think most of the papers I read burned the graphene into a piece of regular non-adhesive polyimide film, and then placed a layer of kapton on top of that to seal it...the graphene can flake off if you're not careful, so the kapton on top makes it more durable. I was running my laser at 40-50mm/s at 80-90% power depending on the situation. Thinner tape needs a bit more finesse since it will flake off easier (or burn through). CO2 laser should work great! The original Nature paper used a CO2, and a lot of followup ones did as well. There are also neat tricks you can do with CO2 like multiple-lasing of Lignin-containing materials like cotton/bread/paper/potato/coconut/etc (see: pubs.acs.org/doi/abs/10.1021/acsnano.7B08539). CO2's wavelength can do a "two-pass" process, where the first pass turns the lignin into amorphous carbon, and subsequent passes start to convert the carbon into graphene. This doesn't work with my 405nm because the amorphorous carbon doesn't absorb 405nm particularly well, unlike CO2. So yeah, should work great. Have fun :)
Oh actually, I just stumbled on this thread while looking for a reference I had misplaced: community.glowforge.com/t/lig-laser-induced-graphene-settings/9707 . Looks like a glowforge user was experimenting with this back in 2017, and lists various power/speed settings and his results :)
@@BreakingTaps It would be interesting to collect some more data on those kind of heaters. Yeah the basic max temperature and max power per area is nice. But I'm thinking resistance over temperature drifting graphs, heat cycling tests, mains voltages heaters with a much higher resistance...
I'll see what I can do! Working on a followup for the supercap side (more tests, better tests, etc)... will see about doing the same for exploring the heater side a bit more. There are some other applications too like stretch/strain sensors and capacitive sensors that might be fun as well :)
Aw man these just keep getting better! Your production quality really shows, I can't imagine how much time must go into each of these shots. Keep up the great work! (Not to mention the great science you keep showcasing, I really like this series where you recreate scientific paper results)
Wow that's really interesting, thanks for sharing the knowledge. You got one more subscriber. Your channel is totally underrated, I came here from a hackaday article; here's hoping for more coverage of your work!!
Re: the validation of the capacitance meter: Regular electrolytic caps often have very high positive tolerances, like for instance 10uF -10% + 50%. The manufacturing process of these can be a bit imprecise, and the tolerances are offset to ensure that you will more or less always get at least the nameplate capacitance. As electrolytics are typically used for filtering/energy storage, getting more capacitance that you expected is pretty much never a bad thing.
What is their idle discharge rate? Like, if you charge a capacitor like this, how quickly does it discharge without load? This is a common problem with capacitor setups without a hard insulator between electrodes.
Pretty fast self-discharge. I didn't measure it quantitatively, but if you leave it sitting around for 10-20 minutes it'll be mostly dicharged when you check back. I wasn't sure if that was due to the process, or my sub-par attempt to fabricate it :)
Kapton is extremely expensive, especially if you're doing a large project where you'll notice it. There are other cheap methods of growing graphene. Positive ions from a superconductive source can form graphene quickly in a vacuum chamber at 10% atmosphere 1800-1900f. There's probably a few ways to create that effect. One is using a pair of tesla coils close to one-another next to the outside of the chamber, firing 2mV and using the right grow medium as co2 gas is slowly vented in.
So great to see the recognition starting to happen for this channel - I keep trying to pump the views a little (I just love rewatching lasers blow polyimide into carbon foam). I'm trying a repeat on this but using a second copper deposit layer for charge collector.
Great detail on this, I found it interesting you used sulfuric acid. For some reason I thought most DIY super caps were using a solution of potassium hydroxide. Still I never knew Kapton tape did that with a laser. Great info. thanks!
Big grain of salt since I'm not an expert, but I believe you can construct alkaline supercaps as well with KOH, NaOH, etc. They just have to be electrostatic double-layer capacitors like this graphene form, but otherwise it doesn't matter if the electrolyte is acidic or basic since you get the same double-layer phenomenon either way. I have seen some papers that show different behaviors depending on the electrolyte used, because the different ion sizes can affect accumulated charge, how quickly they charge/discharge, how it interacts with the electrode material, etc. But yeah, far from an expert so don't trust anything I just said 😀
@@BreakingTaps that is one thing about electrolytic supercaps, the electrolyte can store some energy and move charges via chemical processes in addition to the plate storage.
Just wanted to offer up a big *Thank You!* For your hard work and effort, and for your desire to propagate knowledge which I feel is a noble cause, and can only make the world a better place! If only more people had that same desire, or even the desire to learn, frankly. It seems nobody wants to learn, they just want to *know* if that makes sense.
"I'm not an electronics person" - my friend you're making a capacitor from scratch, and you understand its function. If that isn't an electronics person, I'm not sure what is.
Cool stuff. You may want to test various kinds of space filling curves instead of simple "finger" electrodes, namely: Sierpinski curve and Koch snowflake - source publication: "Fractal-Based Electrolytic Capacitor Electrodes: Scaling Behavior with Respect to Fractal Order and Complexity", Benjamin Barnes, Othman Suleiman, JeanPaul Badjo, Kausik S Das, 2018 Should be rather easy to etch them using a laser.
Frick yeah I'm subscribing and commenting. This came up on my homepage btw... If you like dopamine squirts, check out Shots Of Awe. I would recommend searching RUclips "Technology Shots of Awe"
That heater at the end... if i had the project for it, I'd want to make a PCB reflow bed out of it. I'd love to see some power efficiency numbers just out of curiosity too.
You're getting high measured capacitance, however energy stored in a capacitor is also proportional to the square of the voltage. Did you measure voltage stability? For example, if you make a 150µF capacitor with a max voltage of 1V, an off the shelf electrolytic with 150µF, 16V will be able to store 256 times the energy.
Have you given some serious thought to using a 3D/4D printer (or modified plate printer) to make your pattern, or different design plate platterns, on a grand scale multiplying your plate amount, sizes and different patterns? I think you could really create very powerful and reliable plates or rolls for power and more efficient designs.
Unsure to be honest. I dont have a laser of that wavelength to try, but the UV-Vis spectrum suggests it might be difficult (www.researchgate.net/figure/UV-visible-spectra-of-polyimide-films_fig9_321944400). 450nm seems to be around 40% absorbed, whereas 532 is closer to 25% absorbed. That said, it didn't require 100% power of my laser either, I ran it 90% and fast, but lower powers (20%) work fine if you go slower. So 532nm might work if you slow down a bit
@@BreakingTaps if wavelength doesn't matters may be then we can use black surface under the tape to absorb light for heat generation in specific area but i think wavelength matters
That does it. I'm building my Pi/Arduino laser CNC. I just found this post and it seems like it exactly matches my interests. Manufacturing, electronics, programming and materials.
Thanks for the video, I am trying to reproduce your work at home but use it more as a conductor, I bought a cheap daja laser engraver of 450nm with 3W power, but I cannot seem to get any graphene out. Would it turn black or do I expect a significant resistance drop if I succeed pls? Could you share some settings : power and scanning speed if it is ok? Thank you
Don't know why you call these "super capacitors". Commercially available caps are already available in much higher capacitance values and break down voltages in much more compact packages than what you are demonstrating.
Great Video Yeah a quick scan of digikey will reveal that for aluminum electrolytic capacitors the tolerances can be as wide as -10%/+150% LOL So your capacitance meter was probably more accurate than you might have thought
Two things I'm interested in from this video: 1. Can you make a flexible version of this kapton tape capacitor with Farad levels of storage? Thinking about having a quick charging battery that you could work into a wearable, this seems ideal, even if the "battery" wouldn't last more than an hour (in typical circumstances, who isn't able to get to a wall outlet or at least install a battery inside of an hour?). Home printing a battery I could wrap around my wrist or across my back for example with a reasonable enclosure for durability would be great. 2. The "heater" at the end seems like it would make for a pretty great handwarmer system at super low Voltages, because 285C is a little much for skin, but maintaining a consistent 20-30C across your hand in the winter would be very ideal.
Hello! My name is Elijah and I'm 15 years old. So I watched this awesome video a while ago and just recently I decided to do this for my science fair project. The problem though is that I kept burning through the tape or, on the opposite end of the spectrum, created a thick, inconsistent powder. I was wondering what settings you used and how you made it conductive. It might be my laser engraver. I appreciate any help I can get. Thanks!
HELLS YEAH!!! gonna laser some tape n make a new wafer style heat bed. Can lay it in strips 'tween some flexin plates. hell yeah i only gotta hit 150 max, Dude...Do a video using 'em as hotplates.
I'm a year late to the party but you really should test the self-discharge rate of these and whether they recover voltage after being fully discharged before you start calling them capacitors at all. The capacitance function on multimeters assumes you're giving it a capacitor. If you give it a resistor or an inductor or especially a battery, it will read some erroneous capacitance. You really need an LCR reactance meter that gives you all 3 measurements at a range of frequencies. LCR multimeters don't do that. Again, they're assuming that you're giving them the type of component they're measuring. I've seen a lot of people on YT claim to make supercapacitors and in reality they just make batteries. LCR meter aside, using it in a circuit, like a capacitive voltage doubler would give you an idea of properties like actual, functional capacitance and ESR, which you already know is going to be through the roof. A capacitive voltage doubler should be almost 100 percent efficient. If it ends up being something like 10 percent efficient, you really don't have a capacitor. Still cool, still interesting, just sketchy on the optimism towards its properties.
On the heater application.... Is this something that could be utilized for in-floor heat applications? Currently the art (in-floor heaters) mainly consists hydronic tubes in the floor system. I may be way out in the weeds here, but the thought did cross my mind. (a once-in-a-lifetime experience, so I thought I would celebrate the event by making a comment on your channel....)
Not sure if it's available in the USA but Kapton tape can be got as wide as 100mm which is roughly 4 inches. The other thing that may be of interest is that with regard to the acid, pH is not always a good indicator of suitability to be an electrolyte. EG Boric acid is used commercially in a lot of capacitors which is nothing like as aggressive as sulphuric, and is less toxic. Might be worth a try as it's relatively cheap. One other point is that capacitance meters due to implementing probably the cheapest nastiest way of measuring are almost never accurate (except by accident). Unless you get a Rhode and Schwartz but don't expect change out of 50k for a top of the line model. Electrolytic capacitors are also all over the place dependant on manufacturing tolerance, age and how long since it was last formed. Even ceramic capacitors have issues with aging reducing capacitance (it's a ferroelectric effect reversed by heating). The only ones that are not a right pain in the grunock are either waxed paper (which can still explode in a shower of confetti) or polystyrene that crack if exposed to too much light. If you want a cheap accurate way of measuring capacitance then a wheatstone bridge driven from an accurate sine source into a proper differential amplifier (INA117 is not good enough frequency wise but it's good enough in all other specs). Basically a capacitor has a fixed impedance at a fixed frequency that can be measured.
What are these kinds of supercapacitors useful for? I remember being told, about 20 years ago, that super capacitors are ALMOST useful for storing energy, say for a car or a laptop. They can charge quickly and hold a lot of energy. The problem is that if you break one when it's charged you have a bomb. They also leak energy. But the bomb problem is one that batteries have as well, which is why super high capacity batteries are always promised but never happen.
I have such a laser and I intend to play with Kapton tape, but there is one thing I don't het about this, perhaps due to my poor knowledge of EDLCs. I was left with the impression that the separator between the anode and cathode should be dielectric... Like plastic or paper... However if you moisten paper with battery acid it should become conductive, and there should be no barrier for a discharge between the two plates.... that is where my understanding of this thing breaks apart. I see that you are doing exactly this... Moistening paper and there still is capacitance. What am I missing here? Yes I've seen videos about how the two layers in an EDLC work, but those videos always mention that the separator is a dielectric. How exactly is this working as a capacitor, and not just as a cunductor? While I am figuring this out, maybe I'll try a classic dry capacitor by rolling two layers of this stuff separated with cigarette papers :)
You said that the foam-like structure reduces the conductivity of the graphene... how much? Is the resistance too high to be useful as a circuit? I'm interested in trying this to make a diaphragm for planar headphones 🎧. The laser method would allow for an accurate placement of the electromagnetic coils directly onto the kapton substrate, provided that the resistance isn't to high to be usable. Planar speakers and headphones typically use mylar, which has very similar properties to kapton, with thin flat copper (or aluminum) coils attached to the surface with an adhesive. The mylar is then stretched taught in a frame and placed closely over neodymium magnets (sometimes positioned in a halbach array). When a charge is applied the coils repel oscillating the diaphragm. The low mass of the thin mylar sheet makes it ideal for extremely accurate music reproduction, unlike conventional cone 🔊 drivers that are linear, are much higher in mass, and must overcome their own velocity. Because of that, planar drivers are known for their ability to recreate nearly flawless high and mid frequencies (usually above 100hz). However, driving low resistance speakers, counterintuitively, requires a lot of power. It is harder for an amplifier to drive a 2ohm speaker than an 8ohm. I'm thinking the ability to use a laser to create a graphene coil on kapton could allow for a higher number of closely spaced turns, increasing the resistance, while also increasing the field strength of the coils. But if the resistance of the graphene is too high then copper would still be the way to go.
??? 10:46 "uniform heat"... used as a heated print bed for 3d printer??? if the new "heater" is placed under a glass or other print bed plate... would that protect the kapton-graphene enough to get it to print bed temps and hold for hours / days ??? wasnt sure of the duribility... as you mentioned "no spiral paterns" :) edit: what voltage/amps or watts would be necessary for a one cm(2) piece of kapton enduced graphene to get to 70-100C??? and what time it would take to get there or alter... sorry for the long winded edit :)
Awesome stuff. I had to pause the video half-way through to go and try kapton tape on my own laser cutter... Yep.. works like a charm. Fantastic. I can see that I'm going to have some fun with this. Cheers!!
Electrolytic caps are usually +/- 20% tolerance so your measured values are probably fairly accurate. Cool project though. Be interesting to recreate this in my home shop though I need more equipment lol.
I realized my explanation of how these work was vague and poorly worded, sorry! Graphene-based supercaps are a form of electrostatic double-layer capacitors (EDLCs). Charge is stored at the interface between the electrode and electrolyte via electrostatic attraction when charged. Due to the small charge separation EDLCs can charge and discharge very quickly, and the extreme surface area of graphene foam gives a large interface with the electrolyte to improve overall capacitance. That's why the "perimeter" of interdigitated electrodes is important, because more exposed perimeter == more interface opposing the other electrode to accumulate charge.
What goes into selection of optimal electrolyte? What gives kapton tape this property of UV -> graphene? Could you estimate your capacitance economy? Like capacitance per area, volume, dollar, time, etc?
Is this why you use an acid for the electrolyte rather than say an oil like in electrolytic caps? Because the electrolyte must be somewhat conductive?
One other point on you're value measurements... It is not uncommon for capacitors to be manufactured under "tolerance" of 20% or more, so the meter might not be as inaccurate as it looks.
@@donaldviszneki8251 well the tape is plastic made from hydrocarbons.
Laser burns it down to carbon.
Electrostatic? So it's charged by thunderstorms?
Your capacitance meter is likely more accurate than you realize; most commercial capacitors have a fairly wide tolerance from their stated value. Manufacturers data sheets should list the tolerance for each type the produce.
And the tolerance rating is often kind of 'skewed'. Something like +20/-10% of the nominal value is common.
I was hoping someone would mention this
Looked for this comment to upvote
Agreed. One of the caps he tested looked like it was rather old (the 5uF unit). First, if it actually was rated 5uF, it really is old, because anything made after say, 1975 would likely have been a 4.7uF, not a 5uF unit. Anyway, old electrolytic caps tend to become leaky, and leaky caps often read high on capacitance checkers, even though their true capacitance is falling.
+20/-10% is actually a tight tolerance. I have also seen +50/-20% tolerance in datasheets for electrollytics
Awesome project and quantum leap in production quality. Wow. I wish I had the skill / patience to actually setup shots 😬
He's the combination of you and Applied Science. Glad Ben shouted him out!
Stuff Made Here and Applied Science shoutouts?? Your channel is so underrated!
@@Gwallacec2 btw a quantum leap is extremely small. I mean I guess from the perspective of virtual particles it's extremely large, but a quantum leap is like between electron bands
Then again scale becomes a very strange thing to consider eventually so I'll stop there.
To be fair - wives are pretty wiley subjects. Difficult to capture on camera in their natural environment.
Just please don't you also start talking off to one side without anyone else there. It's really distracting because it's so very forced.
Man I am binging on your channel. This is some seriously awesome stuff!
Thanks! Remarkably, I've somehow never stumbled on your channel, starting to queue up videos now myself! :)
@@BreakingTaps I enjoy both of your channels
It would be amazing to see RUclipsrs start a license free movement, I was just watching one guy create spider silk using genetically modified yeast and released the gene sequences he developed under an MIT license. Absolutely amazing, his next step was to actually have the yeast absorb graphine and/or carbon nanotubes to bond them in the silk to make it stronger.
I agree! It's pretty amazing what some of the minds on YT are capable of :) IIRC that was Thought Emporium.... he does some really fantastic work. One of my goals is to help spread knowledge of these interesting papers that are just buried in archives. Would be neat to see what we could accomplish as a group on YT sharing and developing different techniques that would normally end up in a paper or patent.. There are other interesting developments too, like Joe Barnard (BPS.space) working on launching suborbital rockets, etc. I'm happy to see YT being more than _just_ entertainment.
there is a lot of exciting research done by private individuals. you don't have to be a mega corp to invent new tech
Yes, let’s start! Open source and iterative
you should be trying to light at least a led, the experiment will bring " light " in this clip and make more visual for all on the channel ;)
yep, capacitance meters can show a completely irrelevant reading if you just connect a slightly weird resistor-like thing to it... because from the video, i remained unconvinced that the device can actually store some energy.
@@victortitov1740 it works... my group works on this and other things in the lab (a little fancier, granted, but the principle is the same).
That being said, I would have cycled it with a decent sourcemeter, then again, me, laser physicist lab, him, at home ... so.
@@randfee I am currently working on an electrostatic adhesion gripper. They require an input voltage between 1-6kV, so we need materials with high dielectric strength. At the moment we are ordering flexible PCBs with the interdigitated pattern and the space between the electrodes is limited by the dielectric strength of the adhesive. Would you be able to produce them with this method and what material would you use to cover the electrodes?
Welp, this is one of those treats of RUclips: An easy insta-subscribe with a new underappreciated channel.
I look forward to watching your channel eclipse 100k subscribers in the next 6 months.
imagine Ben from Applied Science, Stuff Made Here and Breaking Taps combine one day into one superhuman being, and make the world a perfect place
The other individual would be Todd O. from Project Farm channel -- excellent, realistic testing of stuff you use or need every day....!
They should collab with carykh and build a robot
and the thought emporium
Also;
- Steve Mould
- Mark Rober
- Veritasium
- The Action Lab
- Cody's Lab
- Project Farm
- NileRed
- Kyle Hill
- KYLE.ENGINEERS
- Engineering Explained
- Tom Stanton
- James Bruton
- Etc
Your point about reaching a level of technology in a society where we can do pretty serious testing and innovation in our garages with off-the-shelf components is spot on… This is the future I ordered! Liked and subscribed! 😎👍🏼
every school need to have machine shops and maker spaces and every community needs to have at least one guild hall of sorts where crafts men and women can ply there craft and find young apprentices to share there knowledge with.
absolutely, man, absolutely, i was thinking the same right now.
"There's only so much two dimensional space..."
In a room in the middle of a city, someone working on coastline lengths sighs in the dark.
I wanna go to the kind of party where people demonstrate shit like this to each other. Party tricks where I'm from are usually something like someone opening a beer bottle with their eyebrow.
I know the feeling, I need more productivity and prosperity-minded friends.
I actually have a friendly competition where my friends and I compete to create the coolest mechanical thing based on a theme. At the end of every other month we get together and show it off. You should join us! 😂
@@grahamgrecian1332 oh wow, that's sick. How do you organize this?
@@woulg it's just a few other guys in the honor hall at my college. You should start one too! It's a lot of fun
@@grahamgrecian1332 nice! Will do, thanks
This capacitor seems like it could be useful as the flexure part of a homemade MEMS scale strain gauge, pressure or temperature sensor. Guys like me who are only hobbyists can't afford off the shelf devices just for the hell of it so making them is the only way to go. Lol
The bed heaters on my 3D printers typically have kapton covering them. They also suffer from being inconsistent and take a long time to come up to temperature with DC power (less so with the AC bed heaters), with less heat near the outer edges. If the kapton covering them were the actual heat source then I imagine it would perform MUCH better. :)
I immediately thought about the same thing. Aluminum is often used to spread the heat from the wires of a heater. Lot of the heat is lost to the backside of the plate. So what if you had a glass bed, completely covered with kapton tape and a standard PEI sticker on top of that. Glass is more rigid than aluminium, has lower density, is a fairly poor conductor of heat and even cheap glass sheets are usually flatter than aluminum. So one can have a lighter, more rigid and flatter bed, reduce losses from the backside and get a more uniform heating. Manufacturing this should be very easy too. Just apply kapton tape to the glass, treat it with a laser, run two pieces of copper foil on the sides for power, then apply PEI sticker on top. Or, perhaps a magnetic sticker to enable the use of removable flex sheets.
@@anttiandreimann8456 you'd also have to figure out where to shove the sensor to feed data back to the controller, and hope your PID tuning algorithm works properly. That said, insulation layer, kapton, electrodes and thermistor, then print bed should work really well and keep the heat directed upwards.
@@anttiandreimann8456 You could make the bed heater using the printer itself. Just mount the laser to the print head and run it uniformly over the kapton.
@@AlexanderTzalumen to try it out crudely there's a simpler solution, since the resistance of the "heating mat" shouldn't vary too much with the temperature swings (at max up to ~100°C of swing from ambient, for general 3D printing with "normal" materials) you could even characterize it measuring the temperature with a thermocouple vs PWM percentage of current, and then control it just by using a look up table and not even need a PID controller, as a certain amount of PWM controlled current should provide the same temperature consistently. Although thermal imaging would be necessary to ensure the current is not traveling in just a straight line or area of the mat (think skin-effect) as opposed to through the whole mat, because PWM-ing creates a lot of high frequency harmonics which may (or may not) induce this effect. Might give this a try one day if I get myself a laser, hope someone beats me to it because it sounds promising IMHO
@@markopesevski perhaps, but the marlin firmware used in the majority of hobbiest and consumer 3d printers all use PID controllers for their heating elements, partially for the initial temperature ramp, and also for maintaining temp stability against the various sources of heat loss (radiant losses, ambient air currents, part cooling fans, moving build plate, etc). For a heated build plate, inconsistant temperature can lead to 1st layer delamination, which will cause the print to shift, warp, or fully detach.
Thank you for this channel. Truly. Also face reveal gang
Thanks! And yeah... figured it was about time I stop being lazy and film some talking head stuff :)
The reason for the high values could also be leakage current. Especially on cheap meters, leaky caps can lead to much higher readings than the actual capacitance.
Cane here to say this.
Really good presentation on this... you talk so naturally with no hint of "I'm reading a script" and no "uuum" or "aah" either. Nice smooth editing too.
Just waiting for the youtube algorithm to bless this channel. Great work as usual, I'm using your metallic microlattice video for one of my projects right now.
Oh awesome, lemme know how it goes (or if you run into issues)! :)
@@BreakingTaps Played around with this graphene concept last weekend, turns out it works really great with the 10um co2 lasers, which is mighty convenient. Also turned much more black (vantablack?) than yours. Anyways, do you have a discord server or something? It would be neat to hang around, as I and a few friends are all doing similar stuff as you
@Wid Lay Awesome, glad to hear it! The first LIG papers were done on CO2 iirc, and there are some neat followup papers where they perform multiple passes to turn amorphous carbon into LIG (which isn't possible with shorter wavelengths like mine). Was used to make supercaps on coconuts and potatos as demonstrations :) I wonder if that's why yours was blacker? The literature shows that LIG is a big mess of graphene + amorphous carbon + fullerenes + tubes, so I wonder if the CO2 does a better job of converting some of the non-graphene into graphene? Dunno, but interesting result!
No discord at the moment, but I was just thinking it'd be fun to have a place to gather folks working on similar stuff. Lemme set one up and I'll give you a ping!
@@you2709 Made a discord! discord.gg/R45uCXcEv4 feel free to invite whomever :)
Great research and presentation! The applications for this technique are huge! I'm an electronics engineer. And I think there's a possible fault on the capacitance metering. Multimeters presume you are measuring a capacitor, but electrodes in a acid medium will make a resistor(or RCL equivalent circuit), also may be electro-chemical reactions going on. There is no insulation on your device and electrons are flowing between terminals. It will probably self discharge almost instantly. To measure a capacitor precisely you first need to charge it, disconnect from source, than connect it to a load. Integrate the power it produced and you will have the energy it is able to store.
Ah interesting, does that apply when using a dedicated "capacitance meter"? I had assumed/hoped it had internal circuitry to power the cap to some degree and test it's leakage or something? This is the device I have: www.newark.com/general-tools/cap1500/capacitance-meter-digital-200pf/dp/59P4162 I did find that it self-discharged very quickly just sitting on the bench, and made even worse when poking it with a multimeter :) I'll see about setting up some kind of circuit as you suggest to test it. Thanks for the help! Electronics is definitely not my forte, very much a newbie still :)
@@BreakingTaps Hard to tell what process it uses to measure. But I think you don't have a capacitor(yet). You need an insulating medium between electrodes. For example electrolytic capacitors use aluminum oxide. In a capacitor electrons can't flow between terminals, there should be an insulation, where an electric field will be created to store enery.
@Eduardo Schoenknecht So big grain of salt due to my general ignorance, but my understanding from the literature is that these types of supercaps operate a bit differently. When charged, a helmholtz double layer is formed symmetrically on the electrodes using the ions in the electrolyte (graphene + | - electrolyte + | - graphene), so there isn't actually a dielectric in play here. Just ions associating / disassociating with the graphene at the interface between liquid and solid.
In theory, based on my reading, but as I said I could have that incorrect :)
@@BreakingTaps you are right. And I don't have knowledge on super capacitors chemistry. But I think a special electrolyte is needed, regular diluted sulfuric acid will just conduct electricity.
Roger, thanks for the help! Will do some more reading on my end. I'm itching to see if I can scale this thing up, so might be able to make a more robust v2 at the same time :)
A note on the capacitance meter: electrolytic caps tend to have a very generous tolerance range, skewed up, since for the most part they're used with rectifying circuits for their relatively high capacity. There's a possibility for the real capacitance value to be closer to the meter readings than to the value on the label.
the second camera makes it seem like i'm watching a testimonial; it feels more personal if you talk to the camera you're looking at
Cheers for the feedback! I've heard similar from a few other folks... will try to tone it down in future videos! :)
I've seen this editing style on quite a few channels lately. I'm guessing there is some popular videography instructional video out there that was promoting it.
@@BreakingTaps second camera is a nice touch, you could always just turn towards it, would be nice if you wanna add some extra info or something, like an aside in theatre....or malcolm in the middle haha
or the tangent cam, for when you go to explain something that is a bit off topic or complementary, but please do keep looking at us. tv show style makes me want to switch channels...
I wonder if the graphene heater would work in a bimetallic-like bend actuator.
There's no reason why it shouldn't
156uF is not very much. But how large would a 10F version of this be?
You don’t need the second camera for RUclips, it makes the viewer feel like their not there with you
capacitance reading may be off in this case due to high leakage resistances, you need some type of rlc meter to determine simultaneously Parallel, series resistances AND capacitance. Parallel Resistance is responsible for leakage currents -determines self discharge speed actually, while series resistance is like a series connected resistor - limits the current and has other detrimental effects. But anyways with some clever experimentation I think you can figure out all of them. nice job.
Incredibly impressive project! Now I want to go order a laser from my printer and make use of the big roll of Kapton I've got. =]
Great quality of shots, editing, and sound too. You put out a high quality video sir!
Just your regular off the shelf 5W LASER!!! Yeah I can just walk into a supermarket to get one lol.
The video is stellar, good job!
If styropyro has taught me anything, you can probably find one on ebay, improperly listed with a lower power rating.
They're available as parts for laser cutters
I keep seeing all these hype videos about super tech this and super magic that, but until it can directly improve my life it's nothing more than vaporware.
pretty sure this is not a supercap from the values ive seen.
Awesome Video, Keep up the Great work, love the videos, educational, and informative. Thanks for feeding the publics Intellectual curiosities.
Another small leap for man kind, This is History 101lazers
ion kills Ghosts.Spirts. Unrefracted particles be careful hahaha
Holy crap! Man, thank you so much for making this. I have been wanting to get into working with graphene and you inspired me. Thanks!
Never seen this guy before, but I started watching and couldn't stop because it was such a good video.
Subbed.
A kapton heater based electric countertop skillet sounds awesome. My current one has a very obvious hot ring where the wire heating element is.
Or a kapton toaster.
I assume it's near 100% efficient at turning the electricity into heat right?
This channel is one of my favorites actually, really awesome content. And that laser induced graphene are so versatile that a lot of technological applications can be made with that. Thanks to show us that amazing technique.
If you want a “neat party trick” take a graphite rod and connect it to a 24v battery... it’ll provide heat, light and danger!!
Great project! I'd be interested to see the leakage current and how long the capacitors will hold voltage with no external connections. Leakage current could also influence the readings from your multimeter, so this is something to watch out for.
Forgive the newbie question: I should be able to test this with just an oscilloscope right? Charge up, measure the discharge for a given period of time and then work out the resistance / leakage current from that?
A crude but portable way to check capacitor condition is to put a multimeter across the terminals and see what the resistance stabilises to. Ideally it should be infinite, but you know a motor start capacitor has definitely failed when it has a resistance under a few hundred ohms :). My understanding of the way most multimeters measure capacitance is they time how long it takes for the capacitance to reach a certain voltage from 0v with a known constant current, so any leakage resistance decreases the amount of current charging the capacitor and makes it appear larger in value than it actually is. I have also used an LC meter that seems to use some form of oscillation to measure capacitance and this seems a bit less sensitive, but can still do weird things with high leakage currents.
Just another Applied Science video with changed person and channel and less subs
One important test for your capacitance meter -- put a resistor across it, no capacitance. Does it still try to produce a reading? If so, you need to be cautious about taking the measurements too seriously. Try also measuring DC resistance of the assembled graphene devices. WIth capacitance, the reading will start low and climb, but see if it tops out at some level or rises to effectively infinity (== good capacitor!)
Just found your channel today: love the videos, the level of detail, and pace. I'd been searching an Applied Science like channel and your's is a great addition to my subs. Thanks :)
Electrolytic capacitors are usually +80%, -20% in tolerance.
Woah, that's wild. I had no idea they had such loose tolerances
@@BreakingTaps they don't; the vast majority (like 90% of them) have a tolerance of ± 20%
I did the same thing with my lighter. I call it Bic induced graphine.
I wonder if you could use this for capacitive touch sensors?
it seems to behave like a electrochemical cell rather than a capacitor
Yeah probably, in which case who knows what this cheapo meter would read. This setup has barely any surface area and it's not really different from a printed metal pattern from what I can tell.
Awesome stuff man, really appreciate it ....thanks for the informative content, please share the specs of the laser, if possible the exact item link would be really helpful.
Thanks.
I'm really interested in possibly using this method to build custom caps for rc planes. I'm curious about what you did with the contacts to allow current flow without melting the tape or having any issues. Is there a conductive glue that would work well for this?
Making good contact is unfortunately rather hard. I used copper tape, pressed mechanically against the LIG (that's what the allen keys and clamps are used for in the heating demonstration). A lot of academic papers use silver epoxy.
Love it!! Let's apply this to a wide format printer and start making some big o'l jelly rolls!
I bet you could use a fractal type pattern to maximize the area the graphine. I've seen PCB antennas that exploit this and I wonder if it would work in this case.
That's exactly what I was thinking
If you could make small enough laser lines, then you could make safety eye glass heaters that would defrost safety glasses (or any glasses, goggles) just like car window defrosters.
the glasses aren't usually made of Kapton, so this may require an inert atosphere when etching. Also some protection against the elements is needed.
HEATED FDM PRINTER BED!
Already flexible, stick it to a steel plate and now the heater itself is *above* any magnets you may be using.
Were you running your laser at full power for this, or did you have it dialed down at all? If I can reproduce this on the Glowforge, I'll be pretty happy.
Ooh, I like that! That's a good idea, I wonder how large you can scale these up. I only tested smallish samples, and I dont think I saw any papers that did a big sample (usually only a few inches square). If you try, I think most of the papers I read burned the graphene into a piece of regular non-adhesive polyimide film, and then placed a layer of kapton on top of that to seal it...the graphene can flake off if you're not careful, so the kapton on top makes it more durable.
I was running my laser at 40-50mm/s at 80-90% power depending on the situation. Thinner tape needs a bit more finesse since it will flake off easier (or burn through).
CO2 laser should work great! The original Nature paper used a CO2, and a lot of followup ones did as well. There are also neat tricks you can do with CO2 like multiple-lasing of Lignin-containing materials like cotton/bread/paper/potato/coconut/etc (see: pubs.acs.org/doi/abs/10.1021/acsnano.7B08539). CO2's wavelength can do a "two-pass" process, where the first pass turns the lignin into amorphous carbon, and subsequent passes start to convert the carbon into graphene. This doesn't work with my 405nm because the amorphorous carbon doesn't absorb 405nm particularly well, unlike CO2.
So yeah, should work great. Have fun :)
Oh actually, I just stumbled on this thread while looking for a reference I had misplaced: community.glowforge.com/t/lig-laser-induced-graphene-settings/9707 . Looks like a glowforge user was experimenting with this back in 2017, and lists various power/speed settings and his results :)
@@BreakingTaps It would be interesting to collect some more data on those kind of heaters. Yeah the basic max temperature and max power per area is nice. But I'm thinking resistance over temperature drifting graphs, heat cycling tests, mains voltages heaters with a much higher resistance...
Anyway, love the new format, keep it going !
I'll see what I can do! Working on a followup for the supercap side (more tests, better tests, etc)... will see about doing the same for exploring the heater side a bit more. There are some other applications too like stretch/strain sensors and capacitive sensors that might be fun as well :)
Aw man these just keep getting better! Your production quality really shows, I can't imagine how much time must go into each of these shots. Keep up the great work! (Not to mention the great science you keep showcasing, I really like this series where you recreate scientific paper results)
Thanks, really appreciate it!
*Fuck yeah dude! Here's some dopamine.* _The Singularity Is Near_
i was like, _who's breaking taps?_ noice channel name bruh. i dont get the entendre tho? you also tap dance or somthin right?
Extremely creative process 👍
Wow that's really interesting, thanks for sharing the knowledge. You got one more subscriber. Your channel is totally underrated, I came here from a hackaday article; here's hoping for more coverage of your work!!
Thanks! Appreciate it :) The YT algorithm moves in mysterious ways :)
I wanna try making long capacitors and rolling them up in a case like an electrolytic capacitor is normally made in . cool idea great vid.
Re: the validation of the capacitance meter: Regular electrolytic caps often have very high positive tolerances, like for instance 10uF -10% + 50%. The manufacturing process of these can be a bit imprecise, and the tolerances are offset to ensure that you will more or less always get at least the nameplate capacitance. As electrolytics are typically used for filtering/energy storage, getting more capacitance that you expected is pretty much never a bad thing.
The meter is probably pretty accurate. Caps can have tolerances of +80% to -20%.
Really cool! Some of my collaborators used LIG. We far preferred to use printed graphene produced by liquid exfoliation. :D
What is their idle discharge rate? Like, if you charge a capacitor like this, how quickly does it discharge without load? This is a common problem with capacitor setups without a hard insulator between electrodes.
Pretty fast self-discharge. I didn't measure it quantitatively, but if you leave it sitting around for 10-20 minutes it'll be mostly dicharged when you check back. I wasn't sure if that was due to the process, or my sub-par attempt to fabricate it :)
Why you used Sulphuric acid ???
“Off the shelf. About 5 Watts.” 🤣
Perfect video
Thanks a lot
Your first video I watched as a random suggestion by RUclips but didn't skip a minute and am subscribing to your channel.
Good production quality on this one, and very interesting content! I like the background.
Thanks! I was hoping to do some chalkboard demos.. but it's not quite smooth enough yet, need to apply a few more layers and keep sanding 🙃
Kapton is extremely expensive, especially if you're doing a large project where you'll notice it. There are other cheap methods of growing graphene. Positive ions from a superconductive source can form graphene quickly in a vacuum chamber at 10% atmosphere 1800-1900f. There's probably a few ways to create that effect. One is using a pair of tesla coils close to one-another next to the outside of the chamber, firing 2mV and using the right grow medium as co2 gas is slowly vented in.
So great to see the recognition starting to happen for this channel - I keep trying to pump the views a little (I just love rewatching lasers blow polyimide into carbon foam).
I'm trying a repeat on this but using a second copper deposit layer for charge collector.
Holy crap I'm 100% trying this after work
Great detail on this, I found it interesting you used sulfuric acid. For some reason I thought most DIY super caps were using a solution of potassium hydroxide. Still I never knew Kapton tape did that with a laser. Great info. thanks!
Big grain of salt since I'm not an expert, but I believe you can construct alkaline supercaps as well with KOH, NaOH, etc. They just have to be electrostatic double-layer capacitors like this graphene form, but otherwise it doesn't matter if the electrolyte is acidic or basic since you get the same double-layer phenomenon either way. I have seen some papers that show different behaviors depending on the electrolyte used, because the different ion sizes can affect accumulated charge, how quickly they charge/discharge, how it interacts with the electrode material, etc.
But yeah, far from an expert so don't trust anything I just said 😀
@@BreakingTaps that is one thing about electrolytic supercaps, the electrolyte can store some energy and move charges via chemical processes in addition to the plate storage.
3:10 "Interdigiated".
* INTERDIGITATED :) I know it's a bugger to pronounce, with you changing it throughout the video :)
Awesome stuff! I just found your channel 🙂
Thanks Carl! Big fan of your work over the years :) Really inspiring to see how much you've pushed the state of art with flexible PCBs, motors, etc.
I'd be really interested to know what kind of charge storage properties these have, i.e. what leakage current you get between the electrodes
This was very cool. I can't wait to see your flux capacitor ;) Happy New Year and thanks for the video.
Just wanted to offer up a big *Thank You!*
For your hard work and effort, and for your desire to propagate knowledge which I feel is a noble cause, and can only make the world a better place! If only more people had that same desire, or even the desire to learn, frankly. It seems nobody wants to learn, they just want to *know* if that makes sense.
"I'm not an electronics person" - my friend you're making a capacitor from scratch, and you understand its function. If that isn't an electronics person, I'm not sure what is.
A neat party trick? Haha. You and I go to very different parties. Love the content man keep it up
It's cool to see kepton turn to graphene when hit with a laser ! Great footage :D
Cool stuff. You may want to test various kinds of space filling curves instead of simple "finger" electrodes, namely: Sierpinski curve and Koch snowflake - source publication: "Fractal-Based Electrolytic Capacitor Electrodes: Scaling Behavior with Respect to Fractal Order and Complexity", Benjamin Barnes, Othman Suleiman, JeanPaul Badjo, Kausik S Das, 2018
Should be rather easy to etch them using a laser.
WHat about charge the DIY capacitor and light up a LED to demonstrate it working besides measurements. You got good pro vlog setup here.
Frick yeah I'm subscribing and commenting. This came up on my homepage btw...
If you like dopamine squirts, check out Shots Of Awe. I would recommend searching RUclips "Technology Shots of Awe"
That heater at the end... if i had the project for it, I'd want to make a PCB reflow bed out of it. I'd love to see some power efficiency numbers just out of curiosity too.
You're getting high measured capacitance, however energy stored in a capacitor is also proportional to the square of the voltage.
Did you measure voltage stability?
For example, if you make a 150µF capacitor with a max voltage of 1V, an off the shelf electrolytic with 150µF, 16V will be able to store 256 times the energy.
Have you given some serious thought to using a 3D/4D printer (or modified plate printer) to make your pattern, or different design plate platterns, on a grand scale multiplying your plate amount, sizes and different patterns? I think you could really create very powerful and reliable plates or rolls for power and more efficient designs.
Anyway , it's very Interesting if it works just using polyamide tape .
Can green laser of 532nm also work ? And Power ?
Unsure to be honest. I dont have a laser of that wavelength to try, but the UV-Vis spectrum suggests it might be difficult (www.researchgate.net/figure/UV-visible-spectra-of-polyimide-films_fig9_321944400). 450nm seems to be around 40% absorbed, whereas 532 is closer to 25% absorbed. That said, it didn't require 100% power of my laser either, I ran it 90% and fast, but lower powers (20%) work fine if you go slower. So 532nm might work if you slow down a bit
@@BreakingTaps if wavelength doesn't matters may be then we can use black surface under the tape to absorb light for heat generation in specific area but i think wavelength matters
That does it. I'm building my Pi/Arduino laser CNC. I just found this post and it seems like it exactly matches my interests. Manufacturing, electronics, programming and materials.
Subscribed to the next big channel, 7.800 subscribers, I predict Q4 2021 to be at least 500.000!
Good luck!!!!
5g-Xg ( 24ghz-100ghz) + rectenna + Suppercapacitor strips + next gen battery = chargeless phone? Is this future? what do you think?
Thanks for the video, I am trying to reproduce your work at home but use it more as a conductor, I bought a cheap daja laser engraver of 450nm with 3W power, but I cannot seem to get any graphene out. Would it turn black or do I expect a significant resistance drop if I succeed pls? Could you share some settings : power and scanning speed if it is ok? Thank you
Don't know why you call these "super capacitors". Commercially available caps are already available in much higher capacitance values and break down voltages in much more compact packages than what you are demonstrating.
Great Video
Yeah a quick scan of digikey will reveal that for aluminum electrolytic capacitors the tolerances can be as wide as -10%/+150% LOL
So your capacitance meter was probably more accurate than you might have thought
Two things I'm interested in from this video:
1. Can you make a flexible version of this kapton tape capacitor with Farad levels of storage? Thinking about having a quick charging battery that you could work into a wearable, this seems ideal, even if the "battery" wouldn't last more than an hour (in typical circumstances, who isn't able to get to a wall outlet or at least install a battery inside of an hour?). Home printing a battery I could wrap around my wrist or across my back for example with a reasonable enclosure for durability would be great.
2. The "heater" at the end seems like it would make for a pretty great handwarmer system at super low Voltages, because 285C is a little much for skin, but maintaining a consistent 20-30C across your hand in the winter would be very ideal.
Hello! My name is Elijah and I'm 15 years old. So I watched this awesome video a while ago and just recently I decided to do this for my science fair project. The problem though is that I kept burning through the tape or, on the opposite end of the spectrum, created a thick, inconsistent powder. I was wondering what settings you used and how you made it conductive. It might be my laser engraver. I appreciate any help I can get. Thanks!
HELLS YEAH!!! gonna laser some tape n make a new wafer style heat bed. Can lay it in strips 'tween some flexin plates. hell yeah i only gotta hit 150 max, Dude...Do a video using 'em as hotplates.
I'm a year late to the party but you really should test the self-discharge rate of these and whether they recover voltage after being fully discharged before you start calling them capacitors at all.
The capacitance function on multimeters assumes you're giving it a capacitor. If you give it a resistor or an inductor or especially a battery, it will read some erroneous capacitance. You really need an LCR reactance meter that gives you all 3 measurements at a range of frequencies. LCR multimeters don't do that. Again, they're assuming that you're giving them the type of component they're measuring.
I've seen a lot of people on YT claim to make supercapacitors and in reality they just make batteries. LCR meter aside, using it in a circuit, like a capacitive voltage doubler would give you an idea of properties like actual, functional capacitance and ESR, which you already know is going to be through the roof. A capacitive voltage doubler should be almost 100 percent efficient. If it ends up being something like 10 percent efficient, you really don't have a capacitor.
Still cool, still interesting, just sketchy on the optimism towards its properties.
On the heater application....
Is this something that could be utilized for in-floor heat applications? Currently the art (in-floor heaters) mainly consists hydronic tubes in the floor system. I may be way out in the weeds here, but the thought did cross my mind. (a once-in-a-lifetime experience, so I thought I would celebrate the event by making a comment on your channel....)
Not sure if it's available in the USA but Kapton tape can be got as wide as 100mm which is roughly 4 inches. The other thing that may be of interest is that with regard to the acid, pH is not always a good indicator of suitability to be an electrolyte. EG Boric acid is used commercially in a lot of capacitors which is nothing like as aggressive as sulphuric, and is less toxic. Might be worth a try as it's relatively cheap. One other point is that capacitance meters due to implementing probably the cheapest nastiest way of measuring are almost never accurate (except by accident). Unless you get a Rhode and Schwartz but don't expect change out of 50k for a top of the line model. Electrolytic capacitors are also all over the place dependant on manufacturing tolerance, age and how long since it was last formed. Even ceramic capacitors have issues with aging reducing capacitance (it's a ferroelectric effect reversed by heating). The only ones that are not a right pain in the grunock are either waxed paper (which can still explode in a shower of confetti) or polystyrene that crack if exposed to too much light. If you want a cheap accurate way of measuring capacitance then a wheatstone bridge driven from an accurate sine source into a proper differential amplifier (INA117 is not good enough frequency wise but it's good enough in all other specs). Basically a capacitor has a fixed impedance at a fixed frequency that can be measured.
What are these kinds of supercapacitors useful for?
I remember being told, about 20 years ago, that super capacitors are ALMOST useful for storing energy, say for a car or a laptop. They can charge quickly and hold a lot of energy. The problem is that if you break one when it's charged you have a bomb. They also leak energy.
But the bomb problem is one that batteries have as well, which is why super high capacity batteries are always promised but never happen.
I have such a laser and I intend to play with Kapton tape, but there is one thing I don't het about this, perhaps due to my poor knowledge of EDLCs.
I was left with the impression that the separator between the anode and cathode should be dielectric... Like plastic or paper...
However if you moisten paper with battery acid it should become conductive, and there should be no barrier for a discharge between the two plates.... that is where my understanding of this thing breaks apart.
I see that you are doing exactly this... Moistening paper and there still is capacitance.
What am I missing here? Yes I've seen videos about how the two layers in an EDLC work, but those videos always mention that the separator is a dielectric.
How exactly is this working as a capacitor, and not just as a cunductor?
While I am figuring this out, maybe I'll try a classic dry capacitor by rolling two layers of this stuff separated with cigarette papers :)
You said that the foam-like structure reduces the conductivity of the graphene... how much? Is the resistance too high to be useful as a circuit?
I'm interested in trying this to make a diaphragm for planar headphones 🎧. The laser method would allow for an accurate placement of the electromagnetic coils directly onto the kapton substrate, provided that the resistance isn't to high to be usable.
Planar speakers and headphones typically use mylar, which has very similar properties to kapton, with thin flat copper (or aluminum) coils attached to the surface with an adhesive. The mylar is then stretched taught in a frame and placed closely over neodymium magnets (sometimes positioned in a halbach array). When a charge is applied the coils repel oscillating the diaphragm.
The low mass of the thin mylar sheet makes it ideal for extremely accurate music reproduction, unlike conventional cone 🔊 drivers that are linear, are much higher in mass, and must overcome their own velocity.
Because of that, planar drivers are known for their ability to recreate nearly flawless high and mid frequencies (usually above 100hz).
However, driving low resistance speakers, counterintuitively, requires a lot of power. It is harder for an amplifier to drive a 2ohm speaker than an 8ohm.
I'm thinking the ability to use a laser to create a graphene coil on kapton could allow for a higher number of closely spaced turns, increasing the resistance, while also increasing the field strength of the coils.
But if the resistance of the graphene is too high then copper would still be the way to go.
The first application for a heater would be Vehicle door mirrors! Made by the millions and a cheap to produce!
Can you make some of these supercapacitors as high a voltage as possible, and send them to ElectroBOOM for testing? 😅 That would be interesting.
??? 10:46 "uniform heat"... used as a heated print bed for 3d printer???
if the new "heater" is placed under a glass or other print bed plate... would that protect the kapton-graphene enough to get it to print bed temps and hold for hours / days ??? wasnt sure of the duribility... as you mentioned "no spiral paterns" :)
edit: what voltage/amps or watts would be necessary for a one cm(2) piece of kapton enduced graphene to get to 70-100C??? and what time it would take to get there or alter... sorry for the long winded edit :)
Awesome stuff. I had to pause the video half-way through to go and try kapton tape on my own laser cutter... Yep.. works like a charm. Fantastic. I can see that I'm going to have some fun with this. Cheers!!
Electrolytic caps are usually +/- 20% tolerance so your measured values are probably fairly accurate.
Cool project though. Be interesting to recreate this in my home shop though I need more equipment lol.