Easy DIY wireless strobing LED light
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- Опубликовано: 18 янв 2022
- A very simple project that allows you to pulse LEDs with no wiring or battery.
The project uses a QI wireless charger to power some LEDs with nothing more than a coil of wire. 
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I work in a retail store that sells these wireless chargers... When they come back as "defective", I have always wanted to test them myself but my phone doesn't charge that way...
This morning I watched this video, and managed to throw together a quick pair of LEDs and a coil I had saved from, I believe, a floppy drive motor... I took it to work and tried it on 2 wireless charging USB lamps... Worked perfectly!!
THANK YOU!!!
If you put a capacitor across the coil (probably 1-10nf) so it resonates with the Qi charger frequency, it will work at a much longer range - may also work better with one LED as this lets the resonance build up more over the previous half-cycle
I've done this a couple of years ago, ten turns and 0.5ųF gave good results.
I used 1,5mm2 solid installation wire, just so the coil looked 'schoolbook' like and steardy.
Exactly what I wanted to write. Small cap and it could work tad better. It's more work and elements but end results is nicer.
If you go even further and measure or calculate the inductance of your coil and choose a capacitor to match the 140kHz oft he QI charger you get even more power and extra long range. I’ve tried this with all the components in series and it works at +20cm distance with eye burning brightness.
GreatScott did a video with the calculations for a QI charger and anything over 0.42mm wire thickness is wasted due to skin effect at this frequency. Using multicore wire improves efficiency and using a ferrite plate nearly doubles the efficiency. Worth a look. ruclips.net/video/3E5PUnYlaTM/видео.html
My dad made a few of these for testing whether race car transponders are transmitting, but with only 1 LED. The previous method he used was listening for noise from an AM radio. The coil of wire with an LED worked so much better in the noisy pit-paddock area of a large race venue.
Fun project.
Check out 7:30 - the green LED seems to be really pulsing at miniscule levels after the initial "high energy check" was done.
You can see the three bright flashes and then tiny dim flashes. Probably some beacon-checks. "High power" checks if presence is there and then just listening for other things.
Edit says:
I really don't want to try this at home and I hope nobody else does it - but I am REALLY intrigued about the forbidden Qi-Charger - the inductive stovetop. My stove has a basic check if it can detect a big enough pot on it to power the coil up completely - I bet this would really flash a big set of LEDs - potentially damaging stuff when used wrong.
I wonder if it would work at all, thinking it is working at a lower frequency. But what could go wrong? Max. some LED's blow up since the heater will more then capable .
ElectroBoom did some things with an inductive cooker
This is really stretching, but I can imagine a use case for this as an ad-hoc power source / transformer for some illicit device in a prison. Perhaps the least plausible part would be a prison kitchen having an induction cooktop to begin with. But, who knows? Maybe they needed a kitchen in a building without any gas lines, and it was more economical to go all electric.
@@Heizenberg32 there are number of other types of electric furnaces, there ain't a reason they'd want inductive one in prison.
@@plainedgedsaw1694 I was thinking an inductive stove top rather than a furnace. Either way, you are right.
I happened to have a small coil (10-20 turns; roughly the diam of your pipe)) of coated steel "fake plant" binding wire on top of my parts rack. So I grabbed two old, albeit tiny, salvaged Red LEDs from a drawer, soldered them together as instructed and soldered the wire to them.
First off... Yes! The solder, albeit with flux applied, DID stick to the wire! Much to my surprise (after stripping the coating of course).
Tested it on my Galaxy S8 was indeed able to momentarily generate a short bright flicker, and then a bunch of barely-visible pulses after, with the bright one occasionally!
However, then I took it a step further and decided to try it out on my Toothbrush charger base, as I knew that was inductive (seems to just be mains fed and nothing else; casing reads 100-130V 50/60Hz - 1.5W ['Murica "Braun" brand]).
It did kkkkind of work, but the LED's coil could fit around the toothbrush so not ideal. So I just grabbed the coil and put one twist, folded it over and that was the perfect size. SIGNIFICANT improvement :P
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I could see this being useful as even an optical display/sensor, for any number of things. Perhaps a passive-security related use where something causes the LED+Coil to fall around the inductor(?) and thus is now lit up to show that it'd been opened since you were last there. Say if you wanted to see if an animal is going somewhere, or maybe a roommate :P
Sure, there's *much* better things for that purpose, but it's hard to beat a toothbrush charger, a coil of wire, and one or two LEDs! lol For a one-time use it's non-invasive, non-destructive, and everything can be easily pulled apart after.
_[/dumb late-night comment]_
This reminds of a small circuit I made where I made a guitar shaped PCB and wound copper wire around it (2000 turns) and soldered 2 smd leds to the end and later potted it in hotglue. Yours has turned out far better than that even with no resin. Mine was made a few years ago when I was still a starter in electronics (still am, but a tiny bit better). The blue tack tric is also really neat since all people don't have helping hands. And mine used both LEDs in parallel so it only turns on every half cycle of the output AC just like in yours.
_„Blu Tack was often used with the Sinclair ZX81 microcomputer to help mitigate crashes caused by wobbly external RAM packs. This was such a widespread problem that Sinclair Research's technical support department officially recommended the use of Blu Tack or electric tape to resolve this issue.”_
@@jkobain Sinclair also used Blu Tack to hold the C5 Wheels on...
Whenever I perform such a «3D-soldering», I tend to take the hardest path and hold the whole contraption with my fingers, and a while ago it also involved holding a piece of ro-osi-i-i-i-i-i-in© with the same hand next to the soldering point. These days I tend to use soldering grease or flux, or a solder wire with rosin core. It was you who with your videos and talks finally convinced me to switch.
And even though I wanted to buy myself those special appliances with magnets, croc clips and rotatable junctions, after such a practice I usually don't need any additional helping hands to solder a bunch of LEDs leg to leg altogether, for instance.
I recently made my own wireless power circuit using a 555 and a mosfet to switch the coil. Making the receiving circuit resonant with a suiting capacitor really made a big difference!
There's a Japanese kit company that used to put out what they called Otona no Kagaku kits (adult science), in the $30-$40 range. (used to, in that they're just re-issuing a few "best of" kits once a year or less now. One of the kits was their "speaker plus", which was a pair of speakers for your mp3 player, plus an inductive coil that would drive a few LEDs, or little LED motor fish that could "swim" in a bowl of water placed within the coil. I reviewed the kit back in 2013 on my science blog. I'd put the URL to the review here, if I knew that I wouldn't get kill-filtered for it.
For much less than $30, you can purchase one of those cheap induction heater drivers from ebay, replace the copper loop with your run of the mill 14-16 gauge wire make a 1.5 turn loop with 50cm to 100cm in diameter and light up as many LEDs as your heart desires. The LEDs just need a coil, attached to them, anything would do (I've made 3 turns of 0.1mm and 5cm diameter coil work with that). If you tune the receiver it greatly increases the distance but as I said basically anything would light up.
Thanks, Clive for showing us what's going on with the wireless chargers. I think I would wind the coil and mount the LEDs on a flat piece of plastic cut from a gallon water bottle. Just something to keep it from getting messed up when I put it in my pocket.
BTW that 0.314 mm wire is about the same as 28 AWG enameled wire. That's about the same as the cheap insulated wire they use inside mouse and keyboard cables. It just so happens that 20 turns at a diameter of 1 inch or 25 mm, times Pi equals about 3 inches per turn or 60 inches total, which is 5 feet or 1.5 meters. That's just about the length of a mouse or keyboard cable. If anyone finds their mouse or keyboard missing a cable... well you know that it was sacrificed for a good cause. ;-)
I've always used White tack or blue tack, to build circuits. It's my go-to helping hand, to hold things in place while I solder them. It's a great way of aligning components with lots of pins and aligning the wires in front of them and solder them all in one go.
Love this! I think it would work great in schools after the standard battery + lamp circuit.
Silicone putty style earplugs also work well for sticking oddly shaped things down. More interestingly it doesn't inhibit platinum cure silicone mold compound or epoxy; works really well for plugging up holes and sticking objects to be molded down into a form so they don't float up when you pour.
A surprise build video this morning. What a way to start the week.
Nice one. I bought a couple of cheap QI charging adaptors that work with most phones. They have a micro USB plug on the end. I used it to power a Raspberry Pi Pico.
heh. You could use that setup with some logic analyzer sw to hack wireless the comm. protocol.
I designed a PCB a while ago with a built in coil and a spot for a single LED, I actually used it to find exactly where the NFC antenna is on my phone. It helps me align it perfectly when I need to use it.
I have made this circuit with transistor (transmitter side)..
It's working perfectly...
In receiver circuit I have used 1 ceramic capacitor parallel to led..
Actually after using the capacitor the brightness of LED dramatically increase...
❤️ Ur all videos...
This is a great project to do with kids. You could even build a little lighthouse or traffic cone, whatever really, or mod an existing toy. Really neat. :)
Been a long while since I've seen anything with an old MPS (Maplin Professional Supplies) label! Many years ago I needed to restock the toolboxes at work with Hellerine sleeve oil & the only place that had the 25ml bottles in stock was MPS at £1/bottle, so I decided to bump it up to a decent value order by ordering 50 off - what turned up was 50x 250ml bottles! Being honest I did ring up customer services to let them know, they told me to keep the ”incorrect items” and they would send out the correct items ... cue the arrival of another 50x 250ml bottles. Next phone call & they decided that I could keep the lot & refund the original purchase as I hadn't got what I ordered... No amount of persuasion would get them to take any back! We worked it out that we'd got enough oil to keep the engineers and production department going for 100+ years 🤣🤣
Their attempt at a "professional" supply service was short and horrible.
@@bigclivedotcom Yeah it does not sound like a good business model was the place laundering money or a tax write off or something? This makes absolutely no damn sense.
@@frizzlefry1921 They were trying to compete with Farnel and RS. They couldn't. I learned the hard way not to spec components from MPS in designs as they often didn't have stock.
Brilliant! I'll have to give that a go.
Thanks for this. I am now going to try and incorporate this idea into some models I've made.
Those are cool, I had successfully made them to work with as little as 3 turns of 0.1mm wire, and you only need 1 LED in practice. So if use use a small enough LED, like those with low profile around 0.2mm height you can embed this kind of thing into card stock without much issue.
Another cool alternative is to use a simple setup of SMD coil + SMD LED, works wonderfully. Anything would work basically. And if you do care about efficiency you can put a capacitor and tune the coil + cap to the transmitter and you have a very bright LED. But the no-brain, just solder stuff up option, works well enough.
To make it work better you can use an induction heater circuit and instead of the small copper loop use a regular wire 1.5 loop with about 50cm in diameter and fill that up with these sort of LEDs.
A brilliant little project, great to get kids into electronics, I love it.
What a good idea that popped into your head after showing us those RF-detecting flashing cell phone stickers!
It was suggested by a few people.
Next project sorted 👌
Thanks Clive
this made me remind a story i think i told you in the past.
long time ago when i was still in high school. i was hired (unofficially) by some entrepreneur guy to fix his business display just before he was going to do a presentation. he basically bought some wireless charger pre-made PCB and were planning to install them inside marble countertops with some nice aluminum CNC trim. it didnt work, and woudnt charge a phone. after some test i discovered that the aluminum trim (like a circle around the top part of the coil) would cancel enough of the magnetic field to prevent the thing from working. it also had an almost 3/4inch thick piece of marble between the coil and the top surface so that didnt help. i simple cut a slit in the aluminum ring and glue a piece of color matched plastic inside of it. after some sanding and everything it looking as new and the setup now worked (barely).
to this day and i dumbfounded to think people woudnt be dumb enough not to know having metal near a magnetic field would act as an antenna and cancel some of it.
Just made one of these and it works surprisingly well with the dinky little NFC field the size of a postage stamp on my phone. It's extremely dim and only works in one very specific spot. lol I don't have a wireless charger, but this store I go to has one on their counter. Maybe they wouldn't mind if I tossed it on there real quick to see. I used a 23mm coil with about 25 turns. I thought maybe since the area on my phone was so small a smaller coil might work better, so I tried wrapping about 45 turns of whatever diameter an AA battery is but it didn't work at all. So I'm guessing unlike what I've been told all my life, size really DOES matter.
Well this looks like quite the fun little project! Never thought of doing this, though of course I'd seen the purpose-built wireless LEDs...
After making a small loop as described & placing over a toothbrush charging post, I got the flickering LED's. Placing the toothbrush on top of the loop to charge the brush the LED's glowed brightly without flicker.
Pretty neat product as ever Clive you make quality videos! Have a nice week
The idea of setting these at mcdonalds makes me think they would make a good christmas tree! Coil at the base of the tree, LEDs in the leaves... set it on the charging pads...
Very Cool Clive that would be a fun project in a classroom !
Ah there they are. And homemade yet. I only just recently saw the compact ones going around the chinesium websites. I love me some LED action. I still need to acquire one of those boards of LEDs that blink randomly like 80's movie computers.
That was a very cool video. simple construction. Many thanks Big Clive :)
A new Clive video 🍻🍻🍻
Awesome!
♥️🇿🇦🤗
Friggin sweet thanks for sharing!
Nice seeing projects that actually work ! Projects that aren't just clickbait free energy crap. (not that I've ever bothered with them, I was born at night, but it wasn't last night. 😆) Thanks B.C.!
"Grandadisanoldman" has been playing with these charging pads the last couple of weeks.. He used chokes recycled from CFL tubes instead of hand-wound coils, and seem quite effective.
Thanks for the shout-out 😊👍
I have a kit from Ali express with some surface mount LED's. I am now foing to makem y own thanks Clive
Nice little project.
Another sleepless night Clive?
Interesting vid - thanks!
I think I'll be making one of these tomorrow evening. (probably with a bit of beer in me) Thanks for an interesting video.
Try it with a simple SMD inductor coil. It works really well and you don't have to fuss about with winding one. Small capacitors across the LEDs will add a strangely pleasing brief fade out effect.
Yeah the fun with this is that basically ANY coil + LED setup works. You don't need anything else. I've made it work with a 5cm diameter loop of 3 turns of 0.1mm enameled copper wire, and those low profile LEDs (0.15mm) which make it as small of a setup that you can embed inside card stock if you wish.
The indicator LED of of a buck converter stared to blink if you put it on the QI charger. (It was car cigarette phone charger) It must be the inductor inside having a voltage induced.
Putting one of those on a phone gave me an idea. An app running as a background service could monitor for incoming calls and trigger a whole bunch of NFC scanning or something, making it work like one of those old phone stickers you showed last week but for modern phones. The circuit could possibly also have something added to mask off the regular scan pulses so it's not flashing all the time, or the app could just turn NFC off if you don't need it for other stuff.
If you go to the effort of making a app that runs on the phone. Could you not simply trigger a built in led like the camera flash?
Haha I love diy wireless coil projects 😝 My toothbrush Phillips charger is just a straight passthrough!
I would expect the closer the tuned value (or harmonic) of the coil/LED network is to the operation frequency of the charging pad (I think it's in the range ~100-200 kHz) the more energy would be transferred and the brighter the LED's. Maybe the main difference between the 10 turns and 20 turns coil
I'd highly recommend thicker gauge wire and incorporating natural frequency. Rolling mills are cool too.
I can see some fun potential for this.
Just had an idea: Fold the LEDs over so that their inside the coil, then pot the whole thing in resin. That way, you get a sturdy flashing button that you can stuff in your pocket, then pull it out and plunk it on the charger at McDonald's.
You don't even need a QI charger to power the LEDs. Simply wind yourself a coil, remove the LED from a Joule Thief circuit, and attach your coil to the output where the LED was. If you match your coils well, the simple circuit will light up LEDs through a 1" thick wooden table. Runs off 1 AA cell also. Use a 2 pin Bi-Color LED, and it will change color when you flip the coil over.
I literally had some PCBs done with a similar circuit based on old crystal radio schematics as sort of a passive RFID / NFC detector and business card combo
You can do this on a more industrial scale, there was a Cumbrian farmer who heated his chicken shed with a massive aerial and a 1KW electric fire, he lived next to a BBC transmitter. It was all quite legal as he had taken care to buy a radio licence which you needed just to listen to the radio til 1971.
There is more fun that can be had with big long inductive loops. Like having a couple in the bottom of your trousers with a driver in your pocket and setting off all of the supermarket trolley locks on people as you walk around in store 😂
From Maplin "Some time ago"!
The phone number on the reel started 0702, the prefix for Southend-on-sea (where Maplin was born), until 1995, so whilst they might have had stock with the old number for a while, it's likely over 25 years old.
And there's a Telex number.
Glad you have your mojo back after a bout of virus. Laissez les bons temps rouler!
Another great video ✌️
Nice video. A lot more detail than a StrangeParts video i saw awhile ago on wireless LEDs.
Those were a different system. I have one on order for detailed exploration.
@@bigclivedotcom yep. It started with the wireless LEDs he found in the Japanese markets iirc; then in the last half of the video he was making his own like with a similar method of wrapping wire around cups and stuff.
Regardless it's all really cool imo and i think with more people doing stuff like this we will see some really cool projects in the future. :)
Nice one Clive
Awesome big Clive
ABOUT AS MUCH USE AS A CHOCOLATE TEACUP. I love it.
What a fun little project!
Also, try making a ring then turn on nearby share on your phone. Ahhh, the joys of being an electrician.
Hi BigClive. I watch your videos every often. These brings great Knowledge and inspiration to me. Man when I see this soldering iron and those screw drivers in your hands, I wish I could have them too but unfortunately I'm in Pakistan and can't have them.
Yes you can. Start small, you don't need to pay $100 for a soldering station, even Clive will actively use his super cheap $14-20 station and it seems like it's never failed him for years. Even then, you can try getting one of those super cheap irons you just plug in the socket they are good enough for most things.
When I started out my soldering iron was a steel rod I jammed into a wood dowel and I heated that over an open flame, I got my tin from old circuit boards... yes, I made my own soldering iron because I couldn't buy even the cheapest one, I recycled soldering tin because I couldn't afford it either and all the electronic components I worked with were salvaged from the trash. I started fixing electronics as a hobby and after I fixed a couple of monitors I had enough for a real soldering iron, then for a spool of tin and so on.
It's not like I have a workshop now, but I do have a fairly full set of tools I have bought one by one over the years, most of them cheap, many of them used, some of them salvaged. To this day I still collect all the waste tin and re-melt it into a big blob I keep around (very useful for tinning thick wires), to this day 90% of the components I use on my for-fun projects are salvaged from the trash.
I'm not as poor as I was before but I am certainly still poor as shit, and if you can read this then you can do it, you can have your own tools even if they aren't many and they are cheap or used, you can create your own projects even if you have to scavenge for components in some e-waste. Adapt and overcome my friend, greetings from Venezuela.
@@Mylity66 yes, cheap soldering irons are 99% perfect for anything, i NEVER bought one of those soldering stations (i'm not referring to hot air guns, those are particular), you can perfectly use a 4$ iron as long as you can find decent solder wire, that makes a difference instead... anyways late sodering irons have silver plated tips and you just need to clean em on a wet cloth after a couple of solderings and it will always be shiny and 100% usable, unlike old types that were made of raw brass and after a single session you had to file or sandpapaper it... YUCK!!
@@redoverdrivetheunstoppable4637 A station is nice though, a cheapy Hakko clone one like the one Clive uses in this video (he showed them in a few videos before, basically he said that " Meh, it's fine" and has been using it ever since 😂) my station was $12 like 10 years ago and you know what? Yeah, it's fine.
They are nice because they get to temperature in 10 seconds and because you can control the temps. But you know what? I still keep a $1 crappy old iron that melted it's original cable and has a freaking nail for a tip (also chewed through that one, brass, so yeah gone in a couple weeks). I can solder copper pipe with that bastard, so much thermal mass.
@@Mylity66 i didn't know you could buy a station for 12$, but nah, i think i'll never buy one... i'm currently using a 6$ adjustable iron (the one with a transparent handle you may have seen around), i don't care much about heating it up in seconds, this is hot in like one minute but also there's not much need for adjustable temp, you just need a powerish one of like 60W and a smaller one with a fine tip... just for being less trash the smaller one can be modified adding a 3 megs resistor from the iron to earth to be a bit safer on ESD components and i also add a coiled telephone cord instead of the power cable to be "out of my balls" instead of having the power cord hanging everywhere on the desk, once you get used to the springy cord this is handy
Fun fact! If you put a Poundland, cigarette lighter phone USB charger, on top of the QI charger the indicator LED blinks. I'm thinking maybe the inductor in the buck converter circuit, is picking up a induced voltage.
It is the first time I was thinking that I watched a video of Bob Ross. 😀 ;-)
Hey! I take the inductor coils and other tiny coils off of motherboards and attach an led to the ends of the wire. It usually makes it flash on a qi charger but the coil size makes the brightness vary. I havent had any break yet.
It also makes different patterns depending on the charger. Some strobe, some do bursts of multiple blinks.
Instructions unclear, can't boot PC
@@dennis8196 ahh. Thats the reason you have to leave the inductor on the computer board and plug all wires together as per the project. then, when ready, plug computer in. not only blimking lights, but actual sparkler effect. This is true because i have seen a sparkler.
@@Palmit_ Followed instructions, produced magic smoke. Rob you could market this.
@@dennis8196 only smoke. same when i tried it but i had sparkles. did you get noises as well like i did?
@@Palmit_ I heard a couple of fizz sounds followed by a loud bang, this is the bit where the magic smoke came out. I know it's magic smoke because it was grey-blue and came after the fizz sounds.
Made one and its really good if you turn on power share on your phone
A very powerful EMF detector, be good to go near a "Danger of death" transformers sub-station with some, a sharrup knafe !
Oh hey, I was wondering about this in the comments of that phone blinker video!
Good for educational purposes also
Pretty neat. Do you think the green / 10 turn worked on the phone because of the fwd voltage characteristics of the green LEDs, or did the number of turns have something to do with it (or both)?
Not sure. Possibly even the thicker wire. I may experiment with that.
That was fun. 👍
Hi Clive, If you leave the phone close enough to turn ON the wireless charging you should be able to power even more LEDs without the strobe effect? I would also add a capacitor though....
You can also do this to transmit sound, I used to make these and see how far away I could get before it became unusable
A 2200uf capacitor would help
Maybe you could design a Christmas holly decoration for the door thats powered in such a fashion.
That’s my afternoon project sorted
- _I've seen other people making these. But they only use a single LED._
Damn, even to me it was pretty obvious that it's certainly better to install two LEDs in reverse-parallel to one another: both because it won't like being reverse-biased at too high voltage, and also this would allow turning energy on the other half of the cycle into light.
:->
very good.
Scare people into NOT using your wireless charger!? Nice 😊👍
Cool.
Oh this looks like fun, I wonder how many LED's you could make it drive, thinking you could make like a mini Christmas Tree and pop it on a Mac'yD charge point and have it flashing away.
I always use a lighter, or sandpaper to strip the enamel off.
"old maplin" indeed - the spool has a telex number on it!
Clive, what would happen if one would but the two LEDs across the leads of a small speaker voice coil, and placed it on the charging base? I'd try it, but I don't happen to have one at this point.
I did a little fiddling with coils and found a 50 turn coil of 28 AWG wire around the same diameter connected to a rectifier could give me 18 volts at enough current to create a small orange spark. My ammeter was acting up, couldn't get a better reading.
Interesting.
that coil could also be used to sense the protocol when a phone involved 👍
I wonder what would happen if you placed one of these on the qi charger and then placed your phone on the charger so it activates the charger. Perhaps with longer leads to the LEDs from the coil. Multiples would be fun too, all around your phone
Haven't seen any inductive chargers in our fast food joints but most of them do offer a standard USB jack at the table. No doubt there is potential there for making some entertaining, annoying or scary gizmos - a black box with an ominous count down timer comes to mind...
try placing coil between Qi pad and a cell phone that's to be charged wirelessly, it should stay solid and may or may not Pulse again once device is done charging
If you put a couple of caps in this quicky circuit, with a small resistor, could you make the LEDs stay on for the length of the pulse, giving the impression it is on all the time?
The enamel wire could easily be taken out of a small transformer!
Also..
I don't have any tac but think I have some C4 lying around, I'll use that!
I use little transformers or coils I have kicking around from old devices.
i suppose the best diameter would be the size of the coils inside a phone since most pads are optimised for them ? then again my earbuds case has a very small coil id assume and charges fine
👍
I have a big collection of cold while leds from swapping leds for warm white.
Maybe I can get rid of a fraction of them for building a bunch of those things.
I wonder how thin and small coil can be to still get enough juice to light both leds. As I have bunch of those tinny little coils that I gather after disassembling random things and some of them have wire thin as hell...
Thank you. What a neat project ideal for children to learn some electronics !! Do the LEDs light up when a magnet moves through the coil? Perhaps I now must build one and find out.
I think the magnet would have to be moving fast.
I wonder if you wanted to make a Christmas tree using those tiny pre soldered train model leds you can get off Banggood or Aliexpress, would you be able to make one coil for the bottom to power all the mini SMD 0603 size or would the circuit need to be a bit more fancy? Considering you would probably use 15 of them and all different colors.
You could power a parallel array of LEDs with one coil.
I don't know how big the coil has to be for it to work with a QI charger, but I built something similar with an SMD inductor. Just for fun (didn't buy anything). I used a 1mH SMD inductor (about 5x5x5mm) desoldered from some random PCB, soldered an SMD LED (also salvaged) across it's contacts and put an SMD MLC capacitor (again salvaged) in parallel on there as well (so it's a 5x5x6mm thing at the end ;) ). I don't know the value of the capacitor, but considering that the LED is the brightest when excited (with a random 40mm coil salvaged from a printer) by around 15kHz, it should be about 100nF (because the resonance frequency of a 1mH/100nF LC circuit is about 15kHz).
If the frequency is given (like on a charger), you could tune the circuit to be resonant at that frequency.