5V USB Portable Solar Power Charger || DIY or Buy
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- Опубликовано: 4 июл 2024
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Solar Cell: s.click.aliexpress.com/e/_dUO...
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In this episode of DIY or Buy I will have a closer look at a commercial 5V USB portable solar power charger. After measuring its output power and pretty much "short reviewing" the product, I will try to make my own DIY version that should cost around the same while outputting more power! Let's get started!
This video was sponsored by Skillshare.
Music:
2011 Lookalike by Bartlebeats 
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The first 1000 people who click the link will get 2 free months of Skillshare Premium: skl.sh/greatscott2
@@Lorenzo_apd he post the vid early for payteron
Dont forget that it needs your credit or debit cards number like Netflix does to give you this two free months
Lorenzo Carelli apd this was a pre uploaded video with set date
the electronic side is a path way to many abilites some consider to be unatural!!!
need video about NB-IOT and LTE-M . Also Available Hardware Products For NB IOT.(like SIMCOMs SIM7000 Module)
You should have built a hinging mechanism in the 3D printed frame itself.
That was also my thoughts too. Otherwise everything else is pretty nice tbh
Maybe some sort of compliant mechanism for reliability?
A barrel and pin system would be super easy for this and probably very sturdy. Could even potentially incorporate the cell connections into the barrels and connect via the pin.
If you've watched GreatScottt's videos for a long time then you know that this type of video where the DIY route is the winner is pretty rare.
True
yup
I did not get why DIY was the winner in this video. It costs the same and you have to invest more time.
@@addygreen8919 maybe because you can get more EXP from this....,
:)
@@addygreen8919 maybe it's because it is more versatile because you can change certain features at your own accord unlike the commercial product where it's difficult to edit to meet your needs. Besides this is an early prototype so he might be able to reduce the cost or improve the product in a later video.
This panel can put out close to 100 watts ruclips.net/user/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.
Me: Sees the video isn't sponsored by JLCPCB
My brain: *panik*
You from Indonesian?
@@wificitranet7232 He's just well-versed in memes
Did you perform the Current Load Test of 10:00 on the commercial product? If the current was limited by your phone, then the maximum current capabilities would be higher too, right?
I tried the test. Result was about the same.
bro he means direct 2 wire system system of 5v charging is limited . by the way we only get 2.4 A max technology for fast charging on 2 wired ampere technology we need data line for increased voltage rather than current for fast charging . some phone go up to 18V+ for fast charging so wire is be thin for more power . and charge pull more to battery.
Some step down boards on AliExpress have a chip to enable fast charging you can try one of these.
@@greatscottlab Then how did the commercial version loose?
Not to mention durability... Those tabs going to hold up to repeated folding and unfolding? I doubt it.
@@greatscottlab Isc only applies in STC = standard test conditions = laboratory conditions of 1000 W/m² and 25°C cell temperature. You would at least need to direct the cells to the sun to get closer to the nominal Isc and Voc
I would love to invite you to our research center, Fraunhofer Center for Silicon-Photovoltaics in Halle.
great scott:diy is winner
me: finally
scott*
@@misterhash9329 thanks I was in hurry that time
The solar tapping wires are going to wear out and break within a few folds, wouldn't they? An MPPT circuit would be a more proper solution than the buck boost converter, maybe try to make a DIY low power MPPT circuit for next project?
And use JLCPCB's SMT assembly service for the custom PCB :D
MPPT would require a load that can absorb a continually variable amount of power. I don't know if all phones would accept a varying power input. This is why in general a battery or supercapacitor is used as an intermediary buffer. Something like USB Power Delivery or one of the proprietary Quick Charge standards might help.
The dodgy wiring can be easily fixed a number of ways. So in my opinion feels largely unimportant just couldnt be bothered to do it properly because its rapid prototyping. Perhaps that should have been stated more clearly when mentioned.
Anyhow more importantly I think the other issue you raise here about MPPT is indeed something that should be addressed and looked into further. I was actually pretty impressed however at how well matched and good performance he managed to get with the off the shelf cheapo buck boost converter. So maybe a good follow up would be a head to head contest between that and a cheap MPPT (or self made one). To see how much benefit for doing it properly. Vs the higher cost of that component. And to see how much power was actually being left on the table. And perhaps gain some useful insight as to why the specific buck boost converter being chosen had worked so well as it did. If it was anything to do with the input stage of the buck boost circuit being in common with the way an MPPT works. Would be great part 2 revisit..
I also wanted to point out that epoxy shrinks by 10% so is not ideal for larger panels that you can see in the video does not dry flat due to the shrinkage or may cause stress or other mechanical issue. And of course 3ed prints are not exactly the stiffest backing material either. So investigating a better protective covering / housing materials would also be worthwhile. If somebody else is trying to repeat this project. I am personally not sure what would be most suitable because there are a number of different options. Which will have different sets of pros / cons. And cost different amounts since this is a budget sensitive project. Just try to avoid the epoxy (if you can find something else better)n is just my main point here, because your standard epoxy will always shrink.
I'd also add atlsast one schotky diode to prevent backflow into the cells, commercially available panels come with one diode per panel but that's probably overkill for something like this.
@@frogjmon unlike an inductive load like a motor, the schotky Diodes in PV-Modules serve to prevent single shaded or broken cells from running in reverse breakdown, which happens in Strings of round about 24 cells (24 * V_forward > 1 * V_revbreakdown. Only applies to crystalline cells.
My favorite day "Great Scott uploads day"
Thanks :-)
"Uplads"
@@-never-gonna-give-you-up- fixed
@@beratbaki1681 it wasn't to drill you into the ground btw :) I tought you did it on purpose haha
You're right
It was interesting watching the PLA frames bend through the time of the project, lol. Great job though!
A hinge system would make it nearly perfect. DIY is definitely the winner here.
Yep, I acutally tried that. But it is really hard to design. At least for me.
And not use PLA for project with a lot of heat :) It will warp!
@@greatscottlab you are too humble. shorten up the taping leads and use small copper braid... Doesn't even need to be insulated and could run uninsulated in the fabric hinges--which are a great idea themselves. I would rubberize one side of the fabric (or use a rubberized or some type of water resistant cushioned fabric) to help with moisture resistance. That's already a pretty big set of cells.
I've made a similar solar charger using 10 solar panels(89 mm x 145 mm for each panel) and a 5v usb converter, and output current was about 1,5 amps in mid day (between 11:00 and 16:00). My solution for hinge mechanism was to use duct tape, it wasn't beautiful but functional. Duct tape can be used for both fabric and hinge use, if anyone is interested I can share the pictures.
Good old duct tape.... Always saves the day!
Nice use of my favourite tech. solution
Share it
If any kid is started engineering they would know that tapes are their best friend. Until they have tools that’s require for doing big project
@@ScrotN I seriously considered buying a sewing machine, but duct tape was a short term solution. I had a 1 week bicycle tour coming in a short time, and went for the quick&dirty solution :)
@@williamlivingston2929 I will definetly shoot a video for that, currently waiting for the aliexpress shipments. My friend "confisticaded" my solar panels:)
GreatScott I had developed that module for my mobile in my engineering college as a mini project but I had used single solar panel of 7 volt and 2 amp and used a Linear regulator lm7805. It was good and fun.
Cells are tested in labs under 1200 watt bulbs at 25°C, reason for the "wrong" readings.
Plus, the epoxy can get opaque and yellowish with time if it's not UV resistant and can't hold the stress of time as it would probably get darker before the panel begins to wear out (if it's under a constant exposure). Should be good for the usage you have in mind though.
It's 1000W/m^2 but besides that I completely agree with you
And dont forget the angle of cell vs. Sun
Unless your garden is located at terrestrial Equator you should tilt your cell according the Sun angle, which depends on latitude, day in year and local suntime
Next proyect could be an automatic two-axis positioner with those factors in mind
The problem I had with epoxy was the expansion and contraction was breaking my cells. That was when I tried to encapsulate them to glass. I think it is better to encapsulate each cell individually.
Good Job!
I only have 1 quick solution that seems to work against the yellowing stuff. Most of those cheap garden lights use those yellowing cells which become useless after a couple of months. I also have a 6V panel that is covered in epoxy and the same thing happened. Sanded all of them to make them ok again but same thing yellowing started again after a month or so. Now I cover them with helicopter tape. The stuff they use to for example protect bike frames. You can get that stuff for a couple of euro. I just cut it and stick it over the cell after I make it clear again. If I now buy new solar stuff which uses those cell I immediately stick it on. The 6V cell is still clear now like all of my other 'toys' after being 3 years in the elements. I might replace the aging tape next year but that is just a 5 minute job.
This is why this plastic crap never lasts in the long run even if it is UV stable there is always mechanical wear and scratching from normal uses that does them in. I always preferred rigid panels with all this in mind.
DIY is the winner. It's not only just about money. It is about understanding how things work and how to make them better. Thank you for the video.
My mom brought home broken solar night lights from work so i built origami style one
It was great to charge my old phone but school bullies smashed it
I guess they don't like renewable energy sources
can't you give them a smash back with a high voltage teaser or something that they will remeber it forever...
@@sarimbinwaseem karma struck back hard on them
One came crawling to my house (broke, unwashed, smelling like death) to ask if my car is still on sale
I did the ultimate sike on him
i was searching for a such of video and i really liked it, it is what i needed for my project thank you.
if you are doing a protable solar panel, I would suggest using Maxeon C60 flexible cells. The cells you are using are more suitable for fixed panels (with tempered glass).
Also in order to harvest maximum energy output of the cell you need to keep it in the most efficient voltage range. Mppt chatger would be a better option instead of buck boost converter.
Last thing is I don't think the cells you are using have any problem, I wouldn't expect you to get more than half of its rated power in germany without pointing the cell directly towards sun.
4.2W output is measured only in 1000w/m2 irradiance with cell pointed directly to sun.
+1 for the C60 cells. 21% efficient and a reasonable ish price
I was just thinking of buying one or building one myself from solar cells but couldn't decide, found this video just in time!
I've also tried to make a portable solar charger some time ago using small 5V epoxy coated solar cells.
I tried to reuse an old solar charger enclosure, as its electronic components were mounted on a separate part, which could easily be slipped out, but not salvaged nor repaired- it was all coated in resin (which, I must say, made it very durable, but not until the charging circuitry and battery worn out).
I encountered the same problem as you did (specs far lower than advertised), so I would get a maximum of 2 watts of power, while the original charger had somewhere around 5 watts - and it was older tech, so still impressive for such a small form factor.
I think that without some built-in energy storage like a supercapacitor or battery using the solar cells alone for power is rather unstable, and adding that would allow to trickle charge even during overcast or winter conditions.
super good finally a fluffy friendly project a simple SysAdmin can understand, good job
Love your videos 👍👍👍,
I've also built my own solar USB charger out of some solar cells and one 12v to 5 v car adapter.
It works very well.
That is really awesome. I also would love to see a MPPT-Circuit explained from you. And a question remaines, how heavily was the Current influenced by laying the Panels flat to the Table? Maybe they got that rating by facing the panel directly to the sun?
On plain USB 5V, most phones limit the charging current to way below 2A. You saw it when you connected the buck/boost converter to your power supply and it was still only charging with 1.4A. But things change with QC (9V 1.8A) or even USB-C PD (5V 3A). Always test with an empty phone battery. The phone limits the charging to below 5W when the battery reaches 80%++
I'm a senior ee student and I can't wait to be independently and start my own projects. Thanks!
Pretty fantastic work, dude! 😃
For a crude version it works amazingly!
Stay safe there! 🖖😊
I love his videos, and i really wait for their videos. By their means Electro Boom and Great Scoot also.
Awesome project, as always. I'm wondering if you can build your own MPPT? It would be for sure interesting and many people would welcome this project :)
Thanks for your work!
Awesome build! You smashed this one
I'm a DJ and have turntables, my initial thoughts of you spreading the epoxy was to pour it on and have something spin the cell slowly to spread it out but if the epoxy hardened slowly, it'll even itself out eventually unless super viscous.
Awesome project again!
Consider replacing the small wires linking the panels with two hinges.
There should be more electromechanical modules, like hinges.
Huge fan from India, planning this while currently watching
Defiantly DIY,I made one of these years ago with corrugated plastic as backing an sticky tape over the cell's, it works a dream
I once thougt about the same.
Then I did my calculations and got a number about 10w Paneel to charge a phone enough for a normal use ( everything lower limits the user).
I compared different products and bought a 10w paneel, a direct usb controller thing and a power box.
The paneel with controller costet togheter 15€, and the bower box because I think that when you want to get the macimum out of sun you have to use all of it, place the paneel with battery strategely and wait for it to collect.
It works extreamly well and the small paneel fits easyly in travel luggage.
It looks a bit bad but I really like it
The DIY setup in the video is a bit overdoing it, but on the other hand it will charge with worse weather conditions!
still very briddle design ^^
5:50 *Electroboom handcrank phone charger*
😂
Your videos are pretty helpful for
Me. Thanks for being there!
Glad you like them!
Yaaay , a DIY winner !!
Everyday learning something new, Amazing Content!!
Great Project Idea. I also built a Solar Charger a year ago and it was very easy and is till now usefull. Can recommend it.
I really love those little buck/boost modules. Super handy for all sorts of projects!
Agreed!
Looking forward to seeing the more improved version of solar charge system
Diy or buy are my fav type of vids
I love the DIY videos great work
Your voice is therapeutic
Great video as always. I have already ordered some solar cells to do a similar project myself. I see you used tab wire all the way the cell (3:57) and only part of it (5:26) is there any difference or I can just solder it partly? Most people solder it all the ways but I don’t know if it is really necessary
Bester Mann! Hab den gleichen Solarlader zu Hause!
Wow very in depth video. Pretty neat
This channel is awesome for computer engineers ❤️
Would be cool if you would do an episode of DIY or buy MPPT's and hook your own MPPT to these cells. I have always been interested in how MPPT's could been made and what results you could expect.
Great Scott! He uploaded!
DIY is the winner if you never leave the garden.
I have exactly the same issues.
I using my DIY for years. and finally got the exact same solar panels that is showing up here.
I can get 1.5 amp from advertised 14W.
the overall for me is to buy on. in this case DIY lose.
Great video. thanks for the efforts. it was very helpful for me.
The hinges was what i didnt get when you showed the cases being printed! its an easy fix to either print extra hinges or better, incorporate hinges in the initial disign. or just use a sheet of thick, stronger fabric, isoloate the sunpanels on the back and use something like velcro to put them on the fabric. Makes it modulair and the fabric is the hinge like the one you bought.
Awesome project!
Mppt and a thermister to temperature compensate the mppt setpoint of the panel this will maximize the available power from the panel. I used a 100W panel for my 7.2A Lipo battery.
Afew weird questions for you @greatScott.
1. What pens do you use? I have always wondered this .
2. Will the epoxy you used yellow in the sunlight?
3 If it does yellow, do you think it will effect your solar output much?
Thank you and keep up the great work.
To improove it even more, you could design another flat case about the same size, and add some flat batteries (just like the one inside the tablets) and a battery charging circuit (tp4056 or 5100) and a boost to 5v. If you use the tp5100, you don't have to worry about higher voltage, since this board has a buck circuit, and can use up to 18v dc in to charge a single battery...
Thanks a lot for this video! I have wanted to make my own DIY solar charger for a half year (because the "buy" ones are very expensive). I already ordered all the parts back in May but are still waiting for the cells to arrive from china
love your videos! keep them going!! have you looked at doing a video about changing olf usb ports on electronics and change them to usb type c?
I think mostly these solar panels provide too less than what is being advertising. Better to use Hetrojunction 28% Efficiency High Grade Solar Panel which is only Made in Europe and mostly used in Space application. But yeah, that is the expensive part.
The economic side, one should check the brand and manufacturer reputation before buying them.
Scott is right, the wattage promised never achived, I have tried it too.
Yeah I’ve only seen one panel or cell ever hit even close to spec (and it went above spec pretty consistently). Almost all of them are way under what they are rated. Really sucks when you are trying to design for a specific load and it drives the size of your design based on an incorrect and made up marketing rating that is simply impossible so then you have to completely redesign because of fake specifications...
Pretty interesting, good job!
Thanks!
First time DIY winner
Just in time thank you for your video.
One question why didn't you use mppt chips for maximum efficiency
For example cN3065 sunny buddy from sparkfun
Good video, i will recommend a elastic cable for connection between this pannel.. so works longer..
Thank you for sharing! Great project! I was looking to get a ready one in the store, but they are expensive (65€)
Awesome, i really appeciate it also, getting such unique ideas is really difficult task
It's my pleasure
I've bought solar cells off Aliexpress and the actual rating is about half the advertised rating. I raised a dispute with photo evidence and got a full refund. I find reading the comments from previous customers useful when buying any solar, laser, or lipo batteries from Aliexpress sellers.
It would be nice if you could go over the process of converting a buck regulator into a constant current driver. For example a driver ic like the lm2596s-adj and adding a current sense resistor and screwing with the feedback pin
Hello scott great project
I love your videos man
Hi Scott! I'm enjoying and learning a lot with your channel about electronics! I'm in the process to buy a 3D printer and my choice is Prusa. I saw your MK3 review and saw on this video that you have the Mini + too, correct? ...how do you like the Prusa Mini and even I have the budget for a MK3, but I'm a beginner, should I go with the Prusa Mini? Any feedback would be greatly appreciated? Thanks
Great video as always! Though I think the tap wire would very easily break from metal fatigue when folding the panel up...
This is how all portable solar panels are made... You don't see it because it is all hidden and protected by the black nylon fabric... Like he should do too...
Looks nice! Your solar cell output power seems to be about the same as my panel (that i bought from amazon)
I added a puck converter that has a lcd display that shows up the amps/volts/watts etc and a lead battery made for security lamps
I've adjusted the output voltage to be a fair bit over 5 volts so that it is able to charge at up to 2 amp hours.. It typically will do about 8-9 watts, I think i need a better puck converter..
I also added leads to connect to car batteries, it works very well!
While the DIY option is the clear winner for price to performance, I feel like the nicely backpack carryable nature and small form factor of the buy makes it a clear winner for practical use
Today I finished the project. Same cells! 10 of them. If I hook it up to a powerbank with 10 18650 LiIon batteries of 2.2 Ah in them, I get around 18 Watt in full sun (So I connected the batteries directly). I also tested with a 6Volt lamp, but it only got 12 Watt at 5 Volts. Clearly the cells perform best at a lower voltage per cell (0.37 Volt per cell). I am thinking of charging LiFePO4 batteries with it, since those like to be filled at round 3.6 Volts, and float round 3.4 Volts. But I am also thinking of making my own MPPT circuit for it, I found one with just 2 NE 555 chips and a few other components!
Epoxy resin is normally too unflexible - differences in thermal expansion between the resin and your cells will most probably crack the cells. Polyurethane solidifies into a more forgiving coating.
I choose option C the data they list for solar cells are super idealized from what I can gather getting anywhere near 40 / 50% of their rated values on a clear sunny day is pretty good and to get near 100 you’d likely need to have no heat, no atmosphere, and perfect lab condition doctored lighting
When I get the notification that GreatScott Uploads when I wake up, I feel so happy and pleased! I have followed your channel since 200 Subscribers, and I knew that you would become amazing like this. Keep Uploading!
Thanks 😁
Love your videos Scott!
But sometimes those testers can stop your phone from drawing quick charge amps (Amps greater than 1) usually.
To test the actual output wattage having an appropriate load is a better way of doing it I feel.
Though I wouldn't be surprised if the cell is a fraction of claimed as that does happen a lot.
I am just speaking from personal experience. You tester might not have that issue.
Thanks again.
At about 3,5v or less the buck boost output voltage rises up to its maximum (30v or more) and it starts consuming an big amount of current from the source, have you experienced something like this ?
3:46 so you didn't have solder before.
Nice to hear that you finally bought solder. Good job :-D
actually the tab wires already have enough solder
Waited a lot 😇
ballbearings make perfect rotating contacts. Simply 3D print sturdy hinges, add the bearings and axles, Vout on the cage, Vin on the axle, and done.
wow genius idea!
Great job great scott I m big fan of u now
Awesome :-)
Good video, i love your videos
Yay! DIY finally won!
A possible solution may be to include a hinge system in the 3d printed parts. Nice video, I really enjoyed all the ideas. Depending on what you want to use the power for, a maximum power system may be possible, maybe a dedicated chip or attiny controller?
Hello, the low short circuit current when you tested with one single cell is probably due to lower light condition from the sun. Isc is provided for 1000W/m2 light intensity, which is quite difficult to reach in Europe. Thanks for the test, I was also about to make a DIY charger !
The short circuit currents given on all those solar cells are rarely reached in practice because they are tested against a reference irradiance of 1kW/m² and a right angle. So the power of those cells is only really realistic near the equator around noon. In Europe you more or less have to divide the advertised power by half, you won't realistically get more than that.
love this series of video's.
12V Solar system panels work well with car USB chargers! The nominal panel voltage is 18V, and the Voc is under the 24V that most car chargers work up to. You can mix and match panel and charger wattage - 5V only (5-12W) or USB power delivery (10-60W). The main problem is no MPPT functionality, so a temporary shadow will collapse the panel output voltage.
A lot of those only go up to 1.5a max and few really put that much on each port when all the ports are in use. The same applies to these overpriced yuppie panels that look nice but rarely deliver regardless of the latitude as some perform like crap even on a good day in Mexico and Spain. A Good one will put out around 2 amps per port and not sag when both ports are in use.
@@MrKillswitch88 I mean panels usually made for charging 12V lead acid battery systems. I have a 25W panel that puts out 25W. It was $40.
@@davidgunther8428 People have been using panels for charging 24v and 48v systems running lithium batteries for a decade or some for homes and businesses. I honestly don't like lead acid batteires as they are bread and eggs that they don't have the best shelf life in the long run. I got lithium packs that are 15+ years old that still hold decent charge.
@@MrKillswitch88 I didn't say I was using lead acid batteries, I said the "12V system nominal" (17V nominal) panels were made for lead acid systems.
@@davidgunther8428 ok....
I think you do a great job and that the tap-wires will soon break.
The sunpower C60 solar cells are the ones to go for. Much stronger mechanically - still fragile, but stronger than the ones you used. All the connections are on the back, which makes wiring them up easier. They have a higher output - you get five amps in strong sunlight at maximum power. Open circuit voltage is a little higher - just over 0.6V. Size is 125mm x 125mm. You can find them on Ali Express. I've used them to build solar-powered radio control planes - no batteries on board at all. Even when the sun goes behind a cloud, or the plane is inverted, there is still enough power from ambient light to work the receiver and servos. An on-board Arduino monitors the voltage and controls the motor speed controller so that the voltage is never pulled too low to cause reception problems. Ten or twelve cells in series seems to be the sweet spot for adequate power with a reasonably-sized model.
Could you go about using a solar panel setup to supplement existing DC power supply to charge or power usb devices? I was thinking of a battery switching circuit but not sure about if it would be effective enough, or it would switch too slowly and damage the usb devices.
Thanks for this project, how can you make your cover of solar cells ?
This epoxy can during longtime ? more than the industriel product ?
The blue panel that was bent, was that from sort of heat from the resin causing it to warp or just a accidental drop?
I would love to see more of this project (Maby a print in place hinge for 3d case ? ) :)
Love this but would like up scale this for amateur radio where the input voltage is 13,8 volts and the amps would be between 15 and 20 amps
What is the advantage of using solar cell flat wire instead of garden-variety round copper wire? It doesn’t look like the flat is easier to solder, and the flat also appears to be more fragile. I don’t have any flat wire to measure the cross-section, but it seems like the flat would have higher resistance - something that would become more important as the string gets longer. I have some solar cells and have been wanting to do a project like this for a while, so I’d really like to know which one to choose.
I have to ask - did you try your pre-made version on your load bank?
Oh, the joy of soldering individual solar cells and encapsulation... Is that resin good with solar exposure, as i recalled that was one important aspect to choose the product.