That's definitely one reason why I like these experiments. I learned a lot from them and it's such generally applicable stuff that I'm sure it'll come in handy later. e.g. The forming current was much higher for the paper towel and aluminum foil coils cap than for the two plates in a glass cap. Kind of obvious why in hindsight, but when I build something similar in the future I'll know which way to go on the first try. And I'm delighted to hear you're enjoying these. Glad I could reciprocate.
I knew someone was going to say it like that :). It's actually pretty good for a homemade capacitor. They're usually in the pico or nanofarads. I'd try making a super capacitor except that everything I've seen so far looks beyond what I can do.
Yup, I'm very familiar with them since I play with Wimshurst machines too which use Leyden jars. All capacitors store static electricity between two electrodes. A lot of folks think Leyden jars are a special type of capacitor because they are usually called Leyden jars, but really that's just for historical reasons as you mention. It was literally the first capacitor and was discovered by accident in the village of Leyden.
To test voltage rating, connect a volt meter and a variable power supply to the capacitor. Then increase the voltage on the power supply and watch the voltage increase on the meter. When the voltage on the meter all of a sudden drops to 0, the voltage it was reading just before that is the voltage rating. Put a few hundred kilo ohms resistance in series too. I do some in my "How to Make High Voltage Capacitors - Homemade/DIY Capacitors" video. There's a link in this video's description.
Now that you mention it... I remember reading the "maintenance manual" for a Model T Ford online. It included how to roll your own capacitors, I think it was for the starting system.
I intentionally allow youtube to do this, and every time someone watches the ad all the way through, I get some compensation. Without it I couldn't afford the time to do as many as I do.
Electrolytes used in commercial aluminum foil electrolytic capacitors are conductive solutions of organic and/or inorganic acids neutralized with amines or ammonia in various solvents, predominantly butyrolactone and ethylene glycol. To fill your mind with more trivia the method used commercially to prevent the cathode oxidation you noted manufacturers dope the electrolyte with organo-phosphates in low concentration as a stabilizer. An interesting side note, organa-phosphates are the major constituents in binary nerve agents and are inherently quite toxic so never inhale the magic smoke when capacitors fail catastrophically if it can be avoided. lol
Speaking of binary lol it's the future of electric vehicles.binary super capacitors.in concert with ping pong relays that transfer current back and forth via amp metering .allowing the charge to rebuild back and forth eliminating lots of weight and waisted space..but most importantly eliminating need to recharge your vehicle ....the sadly the science is proven to work but corporate greed will not allow us to have it yet.on planet greed.
binary nerve agent? what is the other part? I've known ppl that fumed up a whole lab blowing electrolytic and they didn't show any neurological symptoms other than utter glee.
Organic chemistry. I talked with a chemical engineer once. I told him I wanted to make my own Tetraethylead for my hot rod. He flat out told me I would die in the process. Thirty years later, I can buy E85 fuel at the gas pump. So 12 to 1 compression is no longer a knock, ping, detonation issue.
High capacitance compared to other homemade capacitors made without the chemistry, which are in the nanofarad and picofarad range. I haven't seen anyone do homemade super caps yet. I'd like to give it a try myself once I find out how.
It's a mix of distilled water and baking soda. I mention it at 0:40 in the video. I show me preparing it and refer to my previous video in the series "How to Make Electrolytic Capacitors" video. There's a link to it in the description below this video and on my channel page. But basically you put in a teaspoon of baking soda and stir until it dissolves and repeat until you can't get it to dissolves anymore, around 3 or 4 teaspoons.
Glad you like it! I wondered too! Though it's nothing compared to that monster electrolytic capacitor you got and showed us recently. We'd probably need to use the whole aluminum foil and paper towel rolls and put it in a gallon paint can! :)
I see what you mean but I did it that way so that one tab would be on the inside of the spiral and the other would be on the outside. When the whole thing is rolled up you pretty much need it that way, otherwise there'd be a better chance of them touching.
I put both tabs at one end to submerge it in a jar filled with electrolyte to take care of evaporation. It sounds like yours won't be in a jar. It'll be interesting to see it evaporation affects the electrolyte between the plates. Re 2, more capacitance, the electrolyte is conductive. Only the oxide layer is the insulating dielectric. So the aluminum plates could be 2 feet apart and the capacitance will be the same since the oxide layer will still have the same thickness. Keep us posted.
That makes sense since you'd have a better conductor of charge as the electrolyte plate. But I'd assumed, maybe incorrectly, that only certain electrolytes would make an oxide layer on the aluminum.
I don't know what the limits are, but I imagine there is one. I have read the different electrolytes will give it different characteristics too: operating temperature range, shelf life, ...
That might be good enough for a very big capacitor. IIRC the big cap in my video only got to 17 milliamps when I stopped the forming. I think the bigger the cap, the higher the current it will stop forming at. That makes sense since the bigger the cap, the larger the surface area. Or it might have to do with that these caps have a very thin electrolyte, so resistance through the electrolyte is less.
Enjoyed that, very clear. Could seal it in a formerly leaky TV capacitor can. Electrodes poke out, hotglue at the top. Btw, if you unroll an old electrolytic, the silvered foil works great as Cathode in earth batteries, seems nicely corrosion resistant for long periods, perhaps through being formed and wet all those years.
I haven't done any longevity tests, so I don't know. As soon as you apply voltage to it again, any oxide that degraded, reforms, so as long as you water doesn't evaporate I don't see why it won't last a long time.
No, I didn't do any breakdown voltage test. I just assumed it was in the low single digits. Of course, now that you ask I'm really curious :). Unfortunately I've long since thrown it out. :(
I don't know what the breakdown voltage of my homemade capacitor was, though I doubt it was 300V DC. If you're looking for a replacement then you're probably better off buying one.
I'm pretty sure it's the forming voltage that youbused. If at a later time a higher voltage is applied, it will break through the oxide layer. But if you slowly keep raising the forming voltage keeping the current low, you'll find the oxide layer gets thicker and thicker. And, as the oxide layer gets thicker between the plates, the capacitor's farad raiding drops.
The commercial ones usually contain sodium borate or boric acid along with some ethylene glycol. Each manufacturer has their own mix. What did you end up doing? Is you eye okay?
Do you mean a sandwich of glass+foil+glass+foil+glass+foil+glass+foil+glass? You TCoil must have been quite a hit at the science fair. I hope you had a big booth!
Thanks! I needed to try a high capacitance one so I could make the speaker clicking sound that @realflow100 was having trouble with. And I could refine it more but I'll resist temptation. :)
Really enjoying your channel man, mostly all the electronics stuff. Im a chemical engineer so this topic is well under my belt, but my electronics basis is only moderate; your vids have been a great help in my quest to improve electronics skills with your well working descriptions, as ive been able to go from basics to fabricating power supplies, amplifiers, control circuits, etc from scratch to power/control chemistry based projects cheaply with homemade circuits. Thank you for your time to teach these things. One question im still trying to work out....exploring possibly efficiency improvements of H2/O2 production in electrolysis by possibly mechanically breaking apart "extra" H2O molecules with force rather than e- transfer consuming power with a high frequency A/C signal through closely spaced plates by "pulling" them apart in an extreme electric field. I know it most likely will not work; but i must have projects to feed my mind. My problem is how to build an efficient amplifier for high frequency/high current at relatively low voltage; or how to amplify high freq at all due to inductance losses in transformers etc at high freq. Maybe a switched supply using MOSFETS to drive output current waveform? Any ideas would be much appreceiated
I'm glad to hear you're finding my videos useful. Unfortunately, I don't have any suggestions off-hand for the efficient amplifier which you describe. The only amplifier I've done is this one th-cam.com/video/JtPwxbOgBHw/w-d-xo.html which works for low current.
I think i find the Max Voltage. there is no limit for breakdown voltage ! actually it is possible to make 1000 volt electric capacitor ! you can make capacitor with different voltage. remember the first step of making your electric capacitor. the fisrt voltage which you applied to coat the AL plate with AL2O3, is most MAX voltage that your capacitor can work well because the thickness of AL2O3 layer has a direct relationship with the voltage that you coat the oxide layer with.
I haven't tested breakdown voltage. Added layers of paper towels shouldn't help though. The electrolyte is conductive and the paper towels are soaked in it. The purpose of the paper towels is to keep the aluminum plates apart while the oxide layer forms. After that, the oxide layer is the only insulator. I'm guessing you can't get 12kV breakdown voltage since store bought electrolytic capacitors are never anywhere near that. I've seen hundreds of volts breakdown voltages in store bought ones.
So , more voltage to coat the Oxide layer on the plate,makes thicker Oxide layer and higher breakdown voltage. Also the thicker Oxide layer means less capacitance. for example if you want to make a 110 v capacitor you must coat the plate with 110 v .
Not with an electrolytic capacitor. With an electrolytic capacitor the oxide layer that builds up on the aluminum is the insulating dielectric and it's extremely thin while still being able to handle a lot of voltage. The thinness gives the capacitor a high capacitance. All the thin plastics I've ever used aren't nearly as thin as an oxide layer and so you don't get as high a capacitance. Thin plastic works, just doesn't give the high capacitance.
I was planning on sealing it but forgot about it when I rolled it and selecting a jar. Would have been cool. Is that both silvered foils from a cap that work great or just one of them? I ask because I'm curious how the negative foil in a commercially made electrolytic cap doesn't get oxidized whereas the positive foil does. If only one silvered foil is great for earth battery cathodes and not the other then there's something different about the foils.
"Re 2, more capacitance, the electrolyte is conductive. Only the oxide layer is the insulating dielectric. So the aluminum plates could be 2 feet apart and the capacitance will be the same since the oxide layer will still have the same thickness." I stand corrected. Capacitance depends on plate area, thickness of the oxide layer, & its dialetic constant. Electrolytes are conductive, but they have resitance, but may not add up 2 much over short disances except in some pulse power aplications.
That would be nice! If I could charge it up to 12 volts, that'd be 360,000 joules of energy, or 100 watt hours. Hmmm... A lot for a capacitor but doesn't sound like much after all.
Don't know yet, will find out. All it was, was the use of the foil as the cathode, copper as anode, for constant 0.6V/30uA approx. Was before folks started forming same metals on the forums, in battery experiments. What I did was stuck the foil on a piece of card with white glue. As soil is electrolyte (esp after rain) it can be imagined that 2 pieces of the foil, pre-formed in Baking Soda solution, may accept Earth energies, from lightning storms etc. Either which way, they may never corrode.
Whoa didn't know you mentioned me in it! I guess my problem was not using distilled water. so it was too conductive and just kept eroding the aluminum foil.
I have a few questions. I made a DIY capacitor w/ two larger soup cans and some Saran wrap. I will charge it using 4 AA batteries(NOT NEW!! But not very old, either) or a new 9v battery. Please answer the following: How do I charge it? How long will it take to charge? How will I use the built up power? There seems to be some issues w/ it, I can't make it light up an LED after charging it for a second. Thanks! Love you channel :)
Bob dabiuld Do you mean that one can is inside the other can with the Saran wrap in between the two to keep them from touching? If so the capacitance is very small, probably in the picofarads. To charge it simply connect wires to either side of the battery. Connect the wire going to the positive of the battery to one can. Connect the wire going to the negative of the battery to the other can. Because of the very low capacitance it should charge up in less than a second. However, also because of the very low capacitance, the energy stored in the capacitor will be very small, nothing useful really. You need to make a higher capacitance capacitor so you can store more energy. I just tried it with the rolled up one I make in this video th-cam.com/video/GveI9gXIsHw/w-d-xo.html and it wouldn't even briefly light up a small LED.
great vid. i am wanting to make a capacitor bank for a 12, 000 volt transformer. I am wondering if i can make a series of bottle capacitors and solder them in paralell.. i am not sure how many to make...
12kv transformer: I might sugest a Leyden jar like capacitor. It's not polarised like electrolytic capacitors. And can work with really high voltages. You could make one with pc pipes. Looking up pvc dielectric strength, one may find between 10 to 30 kv of protection per millimeter. 2mm wall pc pipe might protect you between 20-60kv. The dielectric constant for PVC looks like about 4, but probably varies according to frequency.
If you used baking soda like I did in this video then you'd probably become iron man with gas but without the iron part. :) Seriously though, baking soda is used in baking but since it neutralizes acid, even though diluted in water like this, I'm not sure what it would do to your stomach acid.
You could have fliped the top layer aluminum and paper towl around so that the tabs would be on the same but oppisate sides. That would be easer to prevent the tabs from touching.
After so many years I finally discovered the root of the problem why it wouldn't work for me. I need a resistor to limit the current when forming the capacitor! And stepping up the voltage in small increments. Ive managed to get a rolled up capacitor up to 10v and hold great capacity and not too much leakage current without breaking down!!!!
One thing I don't understand is the salted distill water. Isn't the reason we place paper or electrolyte napkin paper between the +\- foil is to completely separate the 2 plates? But when you pour electrolyte on napkin and soak entire capacitor in the salt water. +\- foil plate is no longer separated. Or giant leak. Can u explained how this can boost capacitance? Usually when capacitor has leak. It is consider as a defect a compacitor.
See this other video where I first made a simpler electrolytic capacitor and explain how it works th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html. The napkin paper is there to keep the plates from touching while we form the oxide layer on one of them.
What if I used an entire roll of aluminum foil? With paper towel roll. put inside a round big gallon container that's just a little bigger than the finished rolled up capacitor to keep it steady and not allow too much waste of liquid and material. using distilled water of course. and used a 3v 1A transformer with a bridge rectifier and let it charge until the current dropped to very small amount. How many microfarads would that be? A few thousand or more? My guess would be over 5,000uF or more.
Nope. I'm no tesla coil expert but I quick search turned up that the breakdown voltage is too low and they must be suitable for AC, which electrolytic capacitors are not.
My cap is 100,000µF (0.1F) 30 volts. It would probably be bigger then that! About 200 times the size of the one you made! It might even be as big as a 5 gallon bucket!
If I used a few layers of paper towels and built the oxide layer with progressively higher voltage, what could I get the breakdown voltage to be? I'm looking for maybe 12kV peaks, and I could always put some in series. Lower capacitance wouldn't be a problem as long as it's not ridiculously low like 10nF
nice video, for fun it would be nice to make same type capacitor, but very big! and if i do not have voltmeter, if i just leave it forming and testing resistance with LED every 10 mmins, and when led almost doesn't light up, would it be ready? becouse you can see small light in LED even from small curent and voltage.
I imagine sodium bicarbonate is used here due to its availability, ease of use, and low cost. Are there any superior alternatives to sodium bicarbonate for a diy cap? Alternatives that are maybe slightly more expensive, require a little chemistry or extra work to pull off that create better caps?
vegasbryan Check out en.wikipedia.org/wiki/Electrolytic_capacitor. There's a list there of different electrolytes and plate materials. I'm don't have any experience with any besides what I used in this video.
so what is the limiting voltage we can make such a capacitor with, can we forma 500V cap just by having a 500V psu? is there something special we have to keep in mind when constructing? I mean is all in the forming where the dielectric forms
Is it possible to have a capacitor to supply 60amps for 2 seconds at 4s (14-15 volts)? Where can i find something like this and how much would it weigh?
"Re 2 ..." continued en wikipedia org / wiki / Electron "Because of collisions between electrons and atoms, the drift velocity of electrons in a conductor is on the order of millimeters per second. However, the speed at which a change of current at one point in the material causes changes in currents in other parts of the material, the velocity of propagation, is typically about 75% of light speed" In our case, ion transport speeds will put limits on the the maximum potential current levels.
+John Wensley This is an electrolytic capacitor. The dielectric is an aluminum oxide layer that forms on one of the aluminum foil plates. See the other video I refer to where I explain it in more detail th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html or just see "electrolytic capacitor" on wikipedia.
Another idea: Forgetting about the tabs. Offset the + plate to the left 1.25". Offset the - plate to the right 1.25". That leaves 10.5" plate 2 plate & 8x11 sheets of soaked paper on bottom and inbetween. Any, additional paper overlapps 1/4" as needed. Role it together & press together the foil on the left, then right Benifits include: 1. Less waste 2. Thinner and generally more consistant gap = more capacitance 3. Lower internal resistance & lower internal inductive reactance = greater q
Sorry, but I didn't measure the breakdown voltage/voltage rating. What would be interesting would be to experiment with additives to make the layer stay better, but I'm not good at chemistry. More of an electronics and mechanical person.
Why do you need to form an oxide coating on the aluminium when it already has an oxide coating on it? Or does the coating need to be thicker? My understanding is that the thinner the coating the better the capacitor, so wouldn't it work better just using its natural oxide layer?
That's a good question -- maybe the natural one isn't thick enough, at least that makes sense. If you check for conductivity of a normal sheet of aluminum foil using a multimeter, you find it has negligible resistance -- there's no sign that there's even an oxide layer, even though there is. So it would make a lousy dielectric. However, the layer we form here is an insulating dielectric, so it sounds like we need to make it thicker otherwise it's useless.
Hi, I want to ask if you measured the capacitance? How Many Farazi Was Resulting? What tensine can flow constantly? I'd like to build more supercapacitors to power a DC engine for as long as possible. How many layers and what length should I get to get a supercharger of 3000 Faras and 2.7 V? Thank you.
Yes, see the video at around 8:40. I get 560 microfarad. This isn't a supercapacitor, it's an electrolytic capacitor. You'll need to make it differently for the amount of farads you want. I've never made a supercapacitor so I can't help there.
Does forming voltage=breakdown voltage? Was originally planning on making 100 ELDC supercaps using graphite for a railgun, but now i feel that making a few of these at a much higher voltage is better.
Unfortunately, I don't know what the breakdown voltage was and I didn't think to measure it. I know commercial electrolytic caps come in a variety of breakdown voltages so I don't know what determines it.
RimstarOrg ok... am in a little hole right now and its filling up with water. i have this project to do and i choose to build a cap. but so far the one i built is not holding charge. i used a 1gal jug with the foil on the smooth outer surface and a metal rode in the cover and concentrated salt solution. where did i go wrong?
Jerome Swaby What do you mean by it's "not holding charge"? If you charge up a capacitor and then put a meter across it to measure the voltage, if it's a small capacitance one like I suspect yours is then the small charge will discharge fairly quickly through the meter. I just took a 22 nanofarad capacitor and charged it up to around 2.4 volts. When I connected it to the volt meter, within around 1 second it was already down to 1 volt. The discharge curve for a capacitor is very steep at first and then flattens out once it's dropped by most of its voltage.
No, you need the baking soda for making the oxide layer on the foil. See my other electrolytic capacitor video for more understanding th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html
What if one wants to make a 2-section electrolytic capacitor, kinda like one of the multi-section capacitors with 3 pins or more, usually found in old radios or old tube Television sets?
This is the first I've heard of multi-section capacitors. However, from a quick search it looks like these are just multiple capacitors in a single can so I guess you could just make multiple capacitors instead, unless space is the issue. But as I said, this is the first I've heard of them so there may be subtleties that I'm not aware of.
No, because the two capacitor plates are the electrolyte and the aluminum foil. Between them is a very thin aluminum oxide layer on the aluminum. That oxide layer is an insulator. My video that came before this one explains it in diagrams th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html.
Ashwin Kumar k I didn't test for maximum voltage. I also don't know what would happen if you exceed it. It's possible that when you'd turn off the voltage and go back to normal voltage then it may self-repair, but I don't know that for certain.
+Westchester I've never worked with mylar myself but I know a lot of people have bought and used it for making capacitors. Search on google.com for something like "breakdown voltage mylar" or "dielectric stength mylar" to see how many volts it can handle for a given thickness. Note that it won't have as high a capacitance as the capacitor in this video i.e. won't be able to store as much charge. That's because the dielectric in this video is a very, very thin layer of aluminum oxide, whereas the sheet of mylar would be the dielectric and it's a lot thicker. However, the capacitor in this video can probably handle less than a 100 volts before breaking down whereas a mylar one should be able to handle much more.
Compacitor question: Compacitence= Bigger the effective area + how close the 2 conductive material are close to each other.(commercial made very tight= higher uF, home made hand roll=lower pF) Voltage rating= how strong the material is separate the conductive plate. Thicker the material, further 2 conductive plate is apart, harder to tighten the roll, less compacitence. Is this correct? What determine amp rating? Did some more research yesterday on material. Super compacitor is made from graphene which has highest conductivity then copper... Part I don't understand from your video is that you soak the entire apparatus into the liquid solution. Doesn't that short the 2 conductive plate? Isn't the idea of compacitor is to keep away the biggest area possible between 2 conductive plate with strongest possible at thinnest possible thickness ???
I've never heard of an amp rating for a capacitor. Regarding the fluid in the capacitor, see the video I referred to in the reply I gave this morning to your other comment, specifically the first electrolytic video.
I just watch the video again where you explain the super thin layer is to create insulate layer stop conductivity of soda liquid to alum foil layer... Because it is super thin. It give more compacitence. But once it flake off. It will short out store electricity. Thinking it as water hose, volt is speed water flow through. While diameter of hose is current. Translate it to compacitator. It is the amount of + and - surface touch resistor such as LED light bulb. Most of capacity has high voltage for small amount of time. So it does not do much continue work. So in most of case amp rating do not play it's part. In fact most of case are trying to keep out put Amp + volt lower then it is rated.
That depends on how well the paper gets soaked when wet. The paper towel that I used is there to act as a spacer between two pieces of aluminum foil and also to allow a lot of the liquid to easily move from one foil to the other, so the paper has to be very porus, i.e., have a lot of holes. If the paper stays fairly dry then it won't work. Salt water won't work. It won't form the needed layer. I talk more about electrolytic capacitors here in this other video th-cam.com/video/jF2OqUz0Ddg/w-d-xo.html
Higher voltage is dependent on the thickness of the dielectric and what material the dielelectric is made of. In this case the dielectric is aluminum oxide. See my first electrolytic video about that th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html as well as my video about making high voltage capacitors th-cam.com/video/MPD7skZ8OSoB/w-d-xo.htmlTW Surface and a few other things make higher capacitance. My video about low voltage capacitors talks about that th-cam.com/video/GveI9gXIsHw/w-d-xo.html
Nathaniel Charles, discharge rate of a capacitor depends on two things. Internal resistance and the external load resistance. Things that may effect internal resistance is the distance from the lead to the farthest end of the plate, thickness of the plate, and plate materials. Longer role, thinner plate material, and plate materials made with lower conductive materials will slow a capacitors discharge rate.
That's definitely one reason why I like these experiments. I learned a lot from them and it's such generally applicable stuff that I'm sure it'll come in handy later. e.g. The forming current was much higher for the paper towel and aluminum foil coils cap than for the two plates in a glass cap. Kind of obvious why in hindsight, but when I build something similar in the future I'll know which way to go on the first try. And I'm delighted to hear you're enjoying these. Glad I could reciprocate.
I knew someone was going to say it like that :). It's actually pretty good for a homemade capacitor. They're usually in the pico or nanofarads. I'd try making a super capacitor except that everything I've seen so far looks beyond what I can do.
I thought about doing that. But I had enough demonstrations so I had to stop somewhere. And I'm glad you liked it. :)
Yup, I'm very familiar with them since I play with Wimshurst machines too which use Leyden jars. All capacitors store static electricity between two electrodes. A lot of folks think Leyden jars are a special type of capacitor because they are usually called Leyden jars, but really that's just for historical reasons as you mention. It was literally the first capacitor and was discovered by accident in the village of Leyden.
To test voltage rating, connect a volt meter and a variable power supply to the capacitor. Then increase the voltage on the power supply and watch the voltage increase on the meter. When the voltage on the meter all of a sudden drops to 0, the voltage it was reading just before that is the voltage rating. Put a few hundred kilo ohms resistance in series too. I do some in my "How to Make High Voltage Capacitors - Homemade/DIY Capacitors" video. There's a link in this video's description.
Now that you mention it... I remember reading the "maintenance manual" for a Model T Ford online. It included how to roll your own capacitors, I think it was for the starting system.
I intentionally allow youtube to do this, and every time someone watches the ad all the way through, I get some compensation. Without it I couldn't afford the time to do as many as I do.
How's that wiring out for you?
Electrolytes used in commercial aluminum foil electrolytic capacitors are conductive solutions of organic and/or inorganic acids neutralized with amines or ammonia in various solvents, predominantly butyrolactone and ethylene glycol. To fill your mind with more trivia the method used commercially to prevent the cathode oxidation you noted manufacturers dope the electrolyte with organo-phosphates in low concentration as a stabilizer. An interesting side note, organa-phosphates are the major constituents in binary nerve agents and are inherently quite toxic so never inhale the magic smoke when capacitors fail catastrophically if it can be avoided. lol
Speaking of binary lol it's the future of electric vehicles.binary super capacitors.in concert with ping pong relays that transfer current back and forth via amp metering .allowing the charge to rebuild back and forth eliminating lots of weight and waisted space..but most importantly eliminating need to recharge your vehicle ....the sadly the science is proven to work but corporate greed will not allow us to have it yet.on planet greed.
binary nerve agent? what is the other part? I've known ppl that fumed up a whole lab blowing electrolytic and they didn't show any neurological symptoms other than utter glee.
Organic chemistry. I talked with a chemical engineer once. I told him I wanted to make my own Tetraethylead for my hot rod.
He flat out told me I would die in the process. Thirty years later, I can buy E85 fuel at the gas pump.
So 12 to 1 compression is no longer a knock, ping, detonation issue.
I'm glad you enjoyed it!
High capacitance compared to other homemade capacitors made without the chemistry, which are in the nanofarad and picofarad range. I haven't seen anyone do homemade super caps yet. I'd like to give it a try myself once I find out how.
It's a mix of distilled water and baking soda. I mention it at 0:40 in the video. I show me preparing it and refer to my previous video in the series "How to Make Electrolytic Capacitors" video. There's a link to it in the description below this video and on my channel page. But basically you put in a teaspoon of baking soda and stir until it dissolves and repeat until you can't get it to dissolves anymore, around 3 or 4 teaspoons.
My pleasure. I learned a little too, so thanks for asking!
Glad you like it, and thanks for sharing!
That's incredible, as usual. Keep up the good work, Mr. Rimstar 8)
Glad you like it! I wondered too! Though it's nothing compared to that monster electrolytic capacitor you got and showed us recently. We'd probably need to use the whole aluminum foil and paper towel rolls and put it in a gallon paint can! :)
No, I haven't made cup-caps. The oil sounds like a good idea.
Glad to hear your eye was okay.
No problem. That main thing is that you've got what you need in order to make it.
Very interesting! I have always wondered if it was possible to build a electrolytic capacitor!
Serves you two right... you did the same to me with your last video. :)
I see what you mean but I did it that way so that one tab would be on the inside of the spiral and the other would be on the outside. When the whole thing is rolled up you pretty much need it that way, otherwise there'd be a better chance of them touching.
I put both tabs at one end to submerge it in a jar filled with electrolyte to take care of evaporation. It sounds like yours won't be in a jar. It'll be interesting to see it evaporation affects the electrolyte between the plates.
Re 2, more capacitance, the electrolyte is conductive. Only the oxide layer is the insulating dielectric. So the aluminum plates could be 2 feet apart and the capacitance will be the same since the oxide layer will still have the same thickness.
Keep us posted.
That makes sense since you'd have a better conductor of charge as the electrolyte plate. But I'd assumed, maybe incorrectly, that only certain electrolytes would make an oxide layer on the aluminum.
I don't know what the limits are, but I imagine there is one. I have read the different electrolytes will give it different characteristics too: operating temperature range, shelf life, ...
That might be good enough for a very big capacitor. IIRC the big cap in my video only got to 17 milliamps when I stopped the forming. I think the bigger the cap, the higher the current it will stop forming at. That makes sense since the bigger the cap, the larger the surface area. Or it might have to do with that these caps have a very thin electrolyte, so resistance through the electrolyte is less.
Enjoyed that, very clear. Could seal it in a formerly leaky TV capacitor can. Electrodes poke out, hotglue at the top. Btw, if you unroll an old electrolytic, the silvered foil works great as Cathode in earth batteries, seems nicely corrosion resistant for long periods, perhaps through being formed and wet all those years.
I haven't done any longevity tests, so I don't know. As soon as you apply voltage to it again, any oxide that degraded, reforms, so as long as you water doesn't evaporate I don't see why it won't last a long time.
Please let me know what breakdown voltage you find.
No, I didn't do any breakdown voltage test. I just assumed it was in the low single digits. Of course, now that you ask I'm really curious :). Unfortunately I've long since thrown it out. :(
I don't know what the breakdown voltage of my homemade capacitor was, though I doubt it was 300V DC. If you're looking for a replacement then you're probably better off buying one.
I'm pretty sure it's the forming voltage that youbused. If at a later time a higher voltage is applied, it will break through the oxide layer. But if you slowly keep raising the forming voltage keeping the current low, you'll find the oxide layer gets thicker and thicker. And, as the oxide layer gets thicker between the plates, the capacitor's farad raiding drops.
Oh, railgun. That's why you asked about the breakdown voltage. I guess you'll have to test it and let us know. :)
The commercial ones usually contain sodium borate or boric acid along with some ethylene glycol. Each manufacturer has their own mix. What did you end up doing? Is you eye okay?
500 micro farad is realy good for hand made capacitor, have you ever test what the max voltage of this is ?
Do you mean a sandwich of glass+foil+glass+foil+glass+foil+glass+foil+glass? You TCoil must have been quite a hit at the science fair. I hope you had a big booth!
Thanks! I needed to try a high capacitance one so I could make the speaker clicking sound that @realflow100 was having trouble with. And I could refine it more but I'll resist temptation. :)
Thanks! Will do. :) -Steve
Really enjoying your channel man, mostly all the electronics stuff. Im a chemical engineer so this topic is well under my belt, but my electronics basis is only moderate; your vids have been a great help in my quest to improve electronics skills with your well working descriptions, as ive been able to go from basics to fabricating power supplies, amplifiers, control circuits, etc from scratch to power/control chemistry based projects cheaply with homemade circuits. Thank you for your time to teach these things.
One question im still trying to work out....exploring possibly efficiency improvements of H2/O2 production in electrolysis by possibly mechanically breaking apart "extra" H2O molecules with force rather than e- transfer consuming power with a high frequency A/C signal through closely spaced plates by "pulling" them apart in an extreme electric field. I know it most likely will not work; but i must have projects to feed my mind. My problem is how to build an efficient amplifier for high frequency/high current at relatively low voltage; or how to amplify high freq at all due to inductance losses in transformers etc at high freq. Maybe a switched supply using MOSFETS to drive output current waveform? Any ideas would be much appreceiated
I'm glad to hear you're finding my videos useful. Unfortunately, I don't have any suggestions off-hand for the efficient amplifier which you describe. The only amplifier I've done is this one th-cam.com/video/JtPwxbOgBHw/w-d-xo.html which works for low current.
I think i find the Max Voltage. there is no limit for breakdown voltage ! actually it is possible to make 1000 volt electric capacitor ! you can make capacitor with different voltage. remember the first step of making your electric capacitor. the fisrt voltage which you applied to coat the AL plate with AL2O3, is most MAX voltage that your capacitor can work well because the thickness of AL2O3 layer has a direct relationship with the voltage that you coat the oxide layer with.
I haven't tested breakdown voltage. Added layers of paper towels shouldn't help though. The electrolyte is conductive and the paper towels are soaked in it. The purpose of the paper towels is to keep the aluminum plates apart while the oxide layer forms. After that, the oxide layer is the only insulator. I'm guessing you can't get 12kV breakdown voltage since store bought electrolytic capacitors are never anywhere near that. I've seen hundreds of volts breakdown voltages in store bought ones.
Could you use bandages instead of paper towel?
Wow, nice research on my behalf... Thank you
I'll just jump in my time machine and see how eestor and graphene capacitors will do it. :D
So , more voltage to coat the Oxide layer on the plate,makes thicker Oxide layer and higher breakdown voltage. Also the thicker Oxide layer means less capacitance.
for example if you want to make a 110 v capacitor you must coat the plate with 110 v .
Great videos! Thank you!
Awesome as usual
Not with an electrolytic capacitor. With an electrolytic capacitor the oxide layer that builds up on the aluminum is the insulating dielectric and it's extremely thin while still being able to handle a lot of voltage. The thinness gives the capacitor a high capacitance. All the thin plastics I've ever used aren't nearly as thin as an oxide layer and so you don't get as high a capacitance. Thin plastic works, just doesn't give the high capacitance.
I was planning on sealing it but forgot about it when I rolled it and selecting a jar. Would have been cool.
Is that both silvered foils from a cap that work great or just one of them? I ask because I'm curious how the negative foil in a commercially made electrolytic cap doesn't get oxidized whereas the positive foil does. If only one silvered foil is great for earth battery cathodes and not the other then there's something different about the foils.
"Re 2, more capacitance, the electrolyte is conductive. Only the oxide layer is the insulating dielectric. So the aluminum plates could be 2 feet apart and the capacitance will be the same since the oxide layer will still have the same thickness."
I stand corrected. Capacitance depends on plate area, thickness of the oxide layer, & its dialetic constant. Electrolytes are conductive, but they have resitance, but may not add up 2 much over short disances except in some pulse power aplications.
Thanks, bud.
That would be nice! If I could charge it up to 12 volts, that'd be 360,000 joules of energy, or 100 watt hours. Hmmm... A lot for a capacitor but doesn't sound like much after all.
Don't know yet, will find out. All it was, was the use of the foil as the cathode, copper as anode, for constant 0.6V/30uA approx. Was before folks started forming same metals on the forums, in battery experiments. What I did was stuck the foil on a piece of card with white glue. As soil is electrolyte (esp after rain) it can be imagined that 2 pieces of the foil, pre-formed in Baking Soda solution, may accept Earth energies, from lightning storms etc. Either which way, they may never corrode.
Whoa didn't know you mentioned me in it!
I guess my problem was not using distilled water. so it was too conductive and just kept eroding the aluminum foil.
If you thoroughly oxide, well for anode and cathode, and then reverse polarity with power scource, will it act like a zenner?
thanks for your respond, i will test to find that.
I have a few questions.
I made a DIY capacitor w/ two larger soup cans and some Saran wrap. I will charge it using 4 AA batteries(NOT NEW!! But not very old, either) or a new 9v battery. Please answer the following:
How do I charge it?
How long will it take to charge?
How will I use the built up power?
There seems to be some issues w/ it, I can't make it light up an LED after charging it for a second.
Thanks! Love you channel :)
Bob dabiuld Do you mean that one can is inside the other can with the Saran wrap in between the two to keep them from touching? If so the capacitance is very small, probably in the picofarads. To charge it simply connect wires to either side of the battery. Connect the wire going to the positive of the battery to one can. Connect the wire going to the negative of the battery to the other can. Because of the very low capacitance it should charge up in less than a second. However, also because of the very low capacitance, the energy stored in the capacitor will be very small, nothing useful really.
You need to make a higher capacitance capacitor so you can store more energy. I just tried it with the rolled up one I make in this video th-cam.com/video/GveI9gXIsHw/w-d-xo.html and it wouldn't even briefly light up a small LED.
great vid. i am wanting to make a capacitor bank for a 12, 000 volt transformer. I am wondering if i can make a series of bottle capacitors and solder them in paralell.. i am not sure how many to make...
12kv transformer: I might sugest a Leyden jar like capacitor. It's not polarised like electrolytic capacitors. And can work with really high voltages. You could make one with pc pipes. Looking up pvc dielectric strength, one may find between 10 to 30 kv of protection per millimeter. 2mm wall pc pipe might protect you between 20-60kv. The dielectric constant for PVC looks like about 4, but probably varies according to frequency.
If you used baking soda like I did in this video then you'd probably become iron man with gas but without the iron part. :) Seriously though, baking soda is used in baking but since it neutralizes acid, even though diluted in water like this, I'm not sure what it would do to your stomach acid.
You could have fliped the top layer aluminum and paper towl around so that the tabs would be on the same but oppisate sides. That would be easer to prevent the tabs from touching.
After so many years I finally discovered the root of the problem why it wouldn't work for me.
I need a resistor to limit the current when forming the capacitor! And stepping up the voltage in small increments.
Ive managed to get a rolled up capacitor up to 10v and hold great capacity and not too much leakage current without breaking down!!!!
it's realy interesting ! thank you very much , i will make them for my railgun !
One thing I don't understand is the salted distill water.
Isn't the reason we place paper or electrolyte napkin paper between the +\- foil is to completely separate the 2 plates?
But when you pour electrolyte on napkin and soak entire capacitor in the salt water.
+\- foil plate is no longer separated. Or giant leak.
Can u explained how this can boost capacitance?
Usually when capacitor has leak. It is consider as a defect a compacitor.
See this other video where I first made a simpler electrolytic capacitor and explain how it works th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html. The napkin paper is there to keep the plates from touching while we form the oxide layer on one of them.
What if I used an entire roll of aluminum foil? With paper towel roll. put inside a round big gallon container that's just a little bigger than the finished rolled up capacitor to keep it steady and not allow too much waste of liquid and material. using distilled water of course.
and used a 3v 1A transformer with a bridge rectifier and let it charge until the current dropped to very small amount.
How many microfarads would that be? A few thousand or more? My guess would be over 5,000uF or more.
Nope. I'm no tesla coil expert but I quick search turned up that the breakdown voltage is too low and they must be suitable for AC, which electrolytic capacitors are not.
are you saying that you can not use thin plastic between the plates?
My cap is 100,000µF (0.1F) 30 volts. It would probably be bigger then that! About 200 times the size of the one you made! It might even be as big as a 5 gallon bucket!
If I used a few layers of paper towels and built the oxide layer with progressively higher voltage, what could I get the breakdown voltage to be? I'm looking for maybe 12kV peaks, and I could always put some in series. Lower capacitance wouldn't be a problem as long as it's not ridiculously low like 10nF
wow, so much capacitance :-)
nice video, for fun it would be nice to make same type capacitor, but very big! and if i do not have voltmeter, if i just leave it forming and testing resistance with LED every 10 mmins, and when led almost doesn't light up, would it be ready? becouse you can see small light in LED even from small curent and voltage.
I imagine sodium bicarbonate is used here due to its availability, ease of use, and low cost. Are there any superior alternatives to sodium bicarbonate for a diy cap? Alternatives that are maybe slightly more expensive, require a little chemistry or extra work to pull off that create better caps?
vegasbryan Check out en.wikipedia.org/wiki/Electrolytic_capacitor. There's a list there of different electrolytes and plate materials. I'm don't have any experience with any besides what I used in this video.
Boric acid is the electrolyte used commercially. You need to very accurately control the concentration to get the best results though.
Gordon Lawrence Thanks Gordon. I will check that out and read up on it a bit.
Find out about equilibrium reactions and such like because you are using elecricity to push the reaction
so what is the limiting voltage we can make such a capacitor with, can we forma 500V cap just by having a 500V psu? is there something special we have to keep in mind when constructing? I mean is all in the forming where the dielectric forms
Is it possible to have a capacitor to supply 60amps for 2 seconds at 4s (14-15 volts)? Where can i find something like this and how much would it weigh?
"Re 2 ..." continued
en wikipedia org / wiki / Electron "Because of collisions between electrons and atoms, the drift velocity of electrons in a conductor is on the order of millimeters per second. However, the speed at which a change of current at one point in the material causes changes in currents in other parts of the material, the velocity of propagation, is typically about 75% of light speed"
In our case, ion transport speeds will put limits on the the maximum potential current levels.
+John Wensley This is an electrolytic capacitor. The dielectric is an aluminum oxide layer that forms on one of the aluminum foil plates. See the other video I refer to where I explain it in more detail th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html or just see "electrolytic capacitor" on wikipedia.
the speaker capacitor was probably ok , but it was removing low frequency input on speaker so you didnt hear it pop
Another idea:
Forgetting about the tabs. Offset the + plate to the left 1.25". Offset the - plate to the right 1.25". That leaves 10.5" plate 2 plate & 8x11 sheets of soaked paper on bottom and inbetween. Any, additional paper overlapps 1/4" as needed. Role it together & press together the foil on the left, then right
Benifits include:
1. Less waste
2. Thinner and generally more consistant gap = more capacitance
3. Lower internal resistance & lower internal inductive reactance = greater q
Are these good for Tesla coils?
Of course .
04:48 how did you decide / declare the negative and positive terminals?
There's a diagram on the label that my finger is pointing to at 4:43.
What is the voltage rating? And can you please do a new video with an even more powerful and efficient one? It's been 9 years
Sorry, but I didn't measure the breakdown voltage/voltage rating. What would be interesting would be to experiment with additives to make the layer stay better, but I'm not good at chemistry. More of an electronics and mechanical person.
Why do you need to form an oxide coating on the aluminium when it already has an oxide coating on it? Or does the coating need to be thicker? My understanding is that the thinner the coating the better the capacitor, so wouldn't it work better just using its natural oxide layer?
That's a good question -- maybe the natural one isn't thick enough, at least that makes sense. If you check for conductivity of a normal sheet of aluminum foil using a multimeter, you find it has negligible resistance -- there's no sign that there's even an oxide layer, even though there is. So it would make a lousy dielectric. However, the layer we form here is an insulating dielectric, so it sounds like we need to make it thicker otherwise it's useless.
Could benzyl alcohol be used as the dielectric solution?
I don't know. I'm not familiar with benzyl alcohol.
Hi,
I want to ask if you measured the capacitance?
How Many Farazi Was Resulting?
What tensine can flow constantly?
I'd like to build more supercapacitors to power a DC engine for as long as possible.
How many layers and what length should I get to get a supercharger of 3000 Faras and 2.7 V? Thank you.
Yes, see the video at around 8:40. I get 560 microfarad. This isn't a supercapacitor, it's an electrolytic capacitor. You'll need to make it differently for the amount of farads you want. I've never made a supercapacitor so I can't help there.
can we use vegetable oil or mineral oil INSTEAD of water?
I don't know. Would the oxide layer form in that case? I'm doubting it.
Does forming voltage=breakdown voltage? Was originally planning on making 100 ELDC supercaps using graphite for a railgun, but now i feel that making a few of these at a much higher voltage is better.
Unfortunately, I don't know what the breakdown voltage was and I didn't think to measure it. I know commercial electrolytic caps come in a variety of breakdown voltages so I don't know what determines it.
Guess ill have to experiment with it, thanks, wikipedia does say 100Vmax for water based electrolyte
one question. for how long can this works?
How much Farad did that measure?
See the video at around 8:40. It's around 560microfarads.
RimstarOrg ok... am in a little hole right now and its filling up with water. i have this project to do and i choose to build a cap. but so far the one i built is not holding charge. i used a 1gal jug with the foil on the smooth outer surface and a metal rode in the cover and concentrated salt solution. where did i go wrong?
Jerome Swaby
What do you mean by it's "not holding charge"? If you charge up a capacitor and then put a meter across it to measure the voltage, if it's a small capacitance one like I suspect yours is then the small charge will discharge fairly quickly through the meter. I just took a 22 nanofarad capacitor and charged it up to around 2.4 volts. When I connected it to the volt meter, within around 1 second it was already down to 1 volt. The discharge curve for a capacitor is very steep at first and then flattens out once it's dropped by most of its voltage.
Sir... can i use salt water instead of that baking soda.... please tellme... i will make one
No, you need the baking soda for making the oxide layer on the foil. See my other electrolytic capacitor video for more understanding th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html
Thankyou... very much sir. .
What if one wants to make a 2-section electrolytic capacitor, kinda like one of the multi-section capacitors with 3 pins or more, usually found in old radios or old tube Television sets?
This is the first I've heard of multi-section capacitors. However, from a quick search it looks like these are just multiple capacitors in a single can so I guess you could just make multiple capacitors instead, unless space is the issue. But as I said, this is the first I've heard of them so there may be subtleties that I'm not aware of.
Hi, can you explain displacment current
Thanks cees
what about the capacitor in a valve circut 50uf`s and 300V DC this i have inside of my old Dansette Record Player
Doesnt putting the entire thing in the jar of electrolyte cause it to self discharge fairly quickly?
No, because the two capacitor plates are the electrolyte and the aluminum foil. Between them is a very thin aluminum oxide layer on the aluminum. That oxide layer is an insulator. My video that came before this one explains it in diagrams th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html.
RimstarOrg woah, thanks for the fast reply, didnt expect you to reply on a 6 year old video
What is the maximum voltage for this capacitor. Also what will happen to this cap if we exceed the volt
Ashwin Kumar k I didn't test for maximum voltage. I also don't know what would happen if you exceed it. It's possible that when you'd turn off the voltage and go back to normal voltage then it may self-repair, but I don't know that for certain.
would a Mylar dielectric capacitor be easy to make and be able to handle thousands of volts also?
+Westchester I've never worked with mylar myself but I know a lot of people have bought and used it for making capacitors. Search on google.com for something like "breakdown voltage mylar" or "dielectric stength mylar" to see how many volts it can handle for a given thickness. Note that it won't have as high a capacitance as the capacitor in this video i.e. won't be able to store as much charge. That's because the dielectric in this video is a very, very thin layer of aluminum oxide, whereas the sheet of mylar would be the dielectric and it's a lot thicker. However, the capacitor in this video can probably handle less than a 100 volts before breaking down whereas a mylar one should be able to handle much more.
If I used thicker alum foil such as alum can. Will that increase capacitance or voltage?
No, the thickness of the aluminum doesn't make any difference. It's the surface area which matters.
Compacitor question:
Compacitence= Bigger the effective area + how close the 2 conductive material are close to each other.(commercial made very tight= higher uF, home made hand roll=lower pF)
Voltage rating= how strong the material is separate the conductive plate.
Thicker the material, further 2 conductive plate is apart, harder to tighten the roll, less compacitence.
Is this correct?
What determine amp rating?
Did some more research yesterday on material. Super compacitor is made from graphene which has highest conductivity then copper...
Part I don't understand from your video is that you soak the entire apparatus into the liquid solution. Doesn't that short the 2 conductive plate? Isn't the idea of compacitor is to keep away the biggest area possible between 2 conductive plate with strongest possible at thinnest possible thickness ???
I've never heard of an amp rating for a capacitor.
Regarding the fluid in the capacitor, see the video I referred to in the reply I gave this morning to your other comment, specifically the first electrolytic video.
I just watch the video again where you explain the super thin layer is to create insulate layer stop conductivity of soda liquid to alum foil layer...
Because it is super thin. It give more compacitence. But once it flake off. It will short out store electricity.
Thinking it as water hose, volt is speed water flow through. While diameter of hose is current. Translate it to compacitator. It is the amount of + and - surface touch resistor such as LED light bulb.
Most of capacity has high voltage for small amount of time. So it does not do much continue work. So in most of case amp rating do not play it's part. In fact most of case are trying to keep out put Amp + volt lower then it is rated.
Can i use paper and salt water instead of baking soda and tissue?
That depends on how well the paper gets soaked when wet. The paper towel that I used is there to act as a spacer between two pieces of aluminum foil and also to allow a lot of the liquid to easily move from one foil to the other, so the paper has to be very porus, i.e., have a lot of holes. If the paper stays fairly dry then it won't work. Salt water won't work. It won't form the needed layer. I talk more about electrolytic capacitors here in this other video th-cam.com/video/jF2OqUz0Ddg/w-d-xo.html
@@RimstarOrg thanks for the reply!
Surface make higher capacitance. What make higher voltage?
Higher voltage is dependent on the thickness of the dielectric and what material the dielelectric is made of. In this case the dielectric is aluminum oxide. See my first electrolytic video about that th-cam.com/video/ml2TdQ2_2mk/w-d-xo.html as well as my video about making high voltage capacitors th-cam.com/video/MPD7skZ8OSoB/w-d-xo.htmlTW Surface and a few other things make higher capacitance. My video about low voltage capacitors talks about that th-cam.com/video/GveI9gXIsHw/w-d-xo.html
lots of these in my 1920's-1960's vacuum tube radios and amplifiers..and they dry up over time and need to be replaced ....
how to you test for voltage rateing?
Seriously? What info are you missing?
Zip ties.
Could anybody explain me how to minimize the discharge time of a capacitor?
Nathaniel Charles, discharge rate of a capacitor depends on two things. Internal resistance and the external load resistance. Things that may effect internal resistance is the distance from the lead to the farthest end of the plate, thickness of the plate, and plate materials. Longer role, thinner plate material, and plate materials made with lower conductive materials will slow a capacitors discharge rate.
We should make a graphene super cap im down