SWIFT Solar Wide Functional Headlamp, developing and discussing.

Seems like the photos never appears at my end.
As someone already mentioned, we already have “Reylight” branded lights by our member here, and his lights are also sold with the same name over at CPF, so a new name can remove any misunderstanding

SWIFT is a good name :wink:

In simple post editor there is a little icon to add pics, click , paste link in first field, type max.100 in second field and paste link in last field to have the pics show and not be to wide for us phone gazers :slight_smile:

New interface…, it’s like a spacecraft. The first link is for phones? I’ve found a normal database for pics, eh… all night long…everything from the beginning. My apologies, I’ll try to fix it.

Can’t see the pics but sure sound interesting.

Did some fixes. Does everybody can see the photos right now?

I can see the photos now

I am glad you told me about this thread you stated, and I tip my cap to your work and creativity. Nice work!

Thanks for the positive! Hope it’s gonna to be worth it in the end, nope it’s already worth, I keep this device always with me in backpack. Unfortunately the solar panel is often stay lying in the box because there’re lots of power sockets around. But from time to time, we face the adventures!

Nice project! It is interesting to hear about how to make a light as efficient as possible, starting with the solar panel all the way to the amount of light that is produced.
I have litlle input for this because it is very much an electronical thing and that is not my subject.
Keep us informed! :slight_smile:

I do appreciate your interest! I agree, it impresses, when light - produces light. Searching for the li-ion solar charger was a challenge. I digged everything around, it’s very rare IC, even TI Instruments had nothing suitable, I wish, the charger could consume more power but 10W is maximum at the moment. All other components have strong characteristics, for example step-up converter can easily provide 3.5 A (90-97% efficiency depending on li-ion state of charge SOC) load up to 8A maximum, of course it will heat but even an average power bank isn’t always able to do the same.

Tomorrow will be the judgement day, the time to solder a new pcb has come, if something burn out, you might be the fist who hear my voice :slight_smile: Debug path is painful.

By the way, I’ve read your “Springs” test recently, find out it extremely useful. Thank you man. I decided to choose Fasttech ‘carobronze’ because of not high load currents of the single li-ion, current path of the external li-ion will come through the XT30 plug.

Efficiency is the high-ground.

Look forward to your results and further steps you take.

Interesting topic, I am also looking around for solutions to charge li-ions from solar.

Do you know about the CN3722 chip? Here is the datasheet 上海如韵电子有限公司-欢迎访问上海如韵电子有限公司主页!

Here is a ready made charge controller using this chip http://www.ebay.de/itm/181908611611

And here a review of this charge controller Cheap(est?) Lithium MPPT Solar Charge Controller CN3722 - 12v Solar Shed - YouTube

I plan to order this and use a 75W solar panel I already have lying around to charge a 3S li-ion battery pack, should work I hope.

edit: Where do you got the li-ion charger from?

If you can make your led engine fit some headlamp that already exist, it can be popular, you will be able to sell them as transformation kit.
Otherwise making plastic cases on 3D printer by 1pcs will cost more than zebralight for 95% of users.

Yes, it’s well known from me. But as for the efficiency, it doesn’t have a real mppt, so if weather conditions changing, device won’t track solar panel’s IV curve, basically this device is functioning with a static mpp instead of tracking. It will work and not really bad, anyway there’s an issue whether it worth to use advanced system, that in a few times more expensive. Check here, some good fully integrated solar chargers.
http://genasun.com/products-store/mppt-solar-charge-controllers/mppt-for-lithium-batteries/

I’m just worrying about rather high system power, you know… pcb will heat. I’m not sure that it’s possible to load this charger more than 25W without radiator, you should take it into account. As a rule power is growing together with lossless therefore a total efficiency should be in a priority here or not really if you have enough solar power. You know, if it weren’t for so expensive solar W/$ and mppt controllers cost, everything would be ok, that’s why we have to find balance.

I know one man, who’s actively exploiting CN3722 at the moment. As for me, I always read his blog with passion, especially the electronics chapter, but there’s no english language. Here’s is the link. Just try to translate, hope you’ll find it useful.
http://www.shpilev.net/archives/663

Well, I was lucky and bought a few pcs in my local store, when it costed around 3$, but Zmdi company is rebranding to Idt, that’s why this IC haven’t been selling so far. The total cost of the charger’s pcb is about 8$ including all recommending components. You may find test boards on mouser or farnell but they cost quite a lot.

I wish, I could… Look, there’s no suitable headlamp having enough place inside for all this electronics. I might find some examples but they’re not wide spread, their quality and price deserve better.

About the price, I don’t know, what’s a real self-cost of an average zebralight. There’re much more functions in my device, that’s why it’s hard to discuss price difference. It has already cost me 45$. I can’t mark any benefits of zebralight headlamp compared to my fully completed device, except one - more lumens but happiness lies not in lumens.

That’s really nice, when you’re not tied to a certain flashlight. 3D printing has began available as never before, even a kid is able to create a simple model. Prices are mainly depend on the filament and weight. I’m going to spent about 10$ for the first example, it’s not really expensive as seems. No matter, you order 1 pcs or 20 pcs, technology is the same. Therefore I suppose that’s a right direction. After making a 3D model, we could back to this point.

If I were you, I would prefer this charger (link below) to CN3722. Just because it’s TI, pcb probably has better thermal perfomance. I know very well this chip, that was my first acquaintance with this topic.

I would reccomend you to check YZXstudio DIY on Taobao. I have no idea what the voltage of your solar panel, it’s all up to you.
https://shop35123736.world.taobao.com/?spm=a312a.7728559.2015080705.3.JFsoJ7

Try this one, it’s must be the same and still available on sale. There are also chargers for Ni-Mh and Supercap.
http://eu.mouser.com/new/semtech/semtech-ts52001/

Thank you for your suggestion with the BQ24650. This looks like a good match to my 75W panel.

Edit: just ordered a board with this chip

Thread have been updated. “Update 1.”

A food for thought. What type of plugs would you choose? If you had a mini-power bank, that can provide high current 5V output. Especially, when there’s a possibility to connect external li-ion with higher capacity.

I’m using XT30 plugs at the moment, their disadvantage is low compatibility with different interfaces to accelerate the charge process. Usb type-c plugs might be widespread in the nearest future but they’re not serious in front of XT30 due to higher resistance. During the hiking, a tiny plug can be dropped in the mud and become unusable. So compatibility vs efficiency and reliability. On my mind there’s no sense to complicate current concept, you have 2 output wires, all the rest depends on your wishes. Am I on the right way?

About reverse polarity protection. Plugs will not allow to mix up the polarity. There’s only one path to burn the board while inserting the li-ion. Hope everybody has eyes. Yes, sometimes shit happens, it’s sad but also teaches us to be more responsible. I am for consequences :person_facepalming:

Let me know if you wanted to see more detailed DIY (Do It Yourself) guides dedicated to this project.

cool idea. :slight_smile: building Solar-recharged lights always catches my attention. :smiley: