Portable Solar Charger - Pila & 18650's?

[Grrash]

I've got a new Pila charger and several flashlights that use 18650's, and for a long time now I've wanted to get a portable solar panel for camping and emergencies.

Something like this, for example: http://www.rvprotectionproducts.com/index.php?p=product&id=500&parent=253

The description seems to indicate it can easily power my charger, however, after reading numerous CPF threads I'm not so sure anymore. I've searched all over the forums for advice in fact, and it seems like the more I read the more unsure I am about the whole idea.

A flexible panel seemed ideal - but now I'm reading that they are inherently inefficient, lose what efficiency they do have very quickly, they're fragile, generally not UV resistant, don't work unless they are in direct sunlight, and they usually put out a lot less than they are rated for even under the best conditions. I'm getting the idea that it could take weeks to charge a couple of 18650's! The rigid panels are heavy and unwieldy, and it seems that for camping/hiking a bunch of extra batteries is my only reasonable option. Even the folding chargers are going to weigh too much or be too expensive.

It's worth noting that most of the threads I've found were older - has Solar finally caught up with our expectations or am I wasting my time? Is there any SIMPLE solution that doesn't involve reclaiming old panels, custom electronics, or a lot of math?

Just two 18650's... that's all I'm askin'!

:sigh:

 

[roadie]

:welcome:

hmmmm, yr thoughts had been researched many times by many fellow members , including me .....

truth is ... the cheapest way is >> bring along extra extra spare ones

as to charge, its difficult to do that in the wild ......

firstly u need a good relabile solar panel, charging it onto a SLA ..

then use the SLA to power up a hobby charger, thus charging the cells u got.

this project is expensive(3 items) and heavy (SLA), thus its wiser jus to pack more extra battteries ....

 

[Bones]

The panel you linked appears to be a product of PowerFilm Inc. They claim their ThinFilm solar panels are suitable for industrial and military applications, which certainly implies a durable product.

http://www.powerfilmsolar.com/ ... /military_government/

Rather than doing all the research yourself, perhaps you should just ask them which of their products would provide a reasonable amount of power for your Pila charger. I've found their responses to be polite and helpful.

As well, if you can get by with devices powered by NiMH AA cells, they have a number of ready made made solar chargers, including this one which can double as a mobile booster:

http://www.powerfilmsolar.com/ ... /military_government ... usb
-

 

[Grrash]

Yeah, I read everything I could find here on the different solutions, I was hoping to distill it all down. (I don't remember what an "SLA" is but I'm guessing it's an intermittent battery?)

The input on my Pila charger is 6V, 2-3Amps.... I take it that's a whole lot? The 20-watt panels are supposed to put out around 1.2A @15.4V, and like the one I linked to, they claim to be able to charge just about anything and everything.

BTW, I've been to the Powerfilm website, but I haven't called them. I expected they'd give me an "optimal" answer, not real-world solutions like you get from some guy who's actually tried it. I started with the 18650's because if I can charge them, I should be able to charge any AA cells I might use.


:shakehead

 

[roadie]

SLA = sealed lead acid

:kiss:

 

[AnAppleSnail]

One big deal with solar charging is that you will either have a very slow charge, poor charge characteristics, or need large storage to smooth out the power curve during the day.

Ideally the solar cell would output the exact power you need - the Pila charger probably runs a high-then-topoff charge cycle. But the sun doesn't do that, unless you begin charging at the right instant in the afternoon - the light changes all day. If you're filling a lead-acid battery, then you hauled at least a pound of SLA that could have been batteries. On a LONG trip this becomes a good trade - but hope for sunny weather.

 

[KiwiMark]

I've got a new Pila charger and several flashlights that use 18650's, and for a long time now I've wanted to get a portable solar panel for camping and emergencies.

Something like this, for example: http://www.rvprotectionproducts.com/index.php?p=product&id=500&parent=253

How long are you camping for at a time? i.e. how long are you away from power of any kind? And what are emergencies? If you have access to an automotive battery then there are plenty of 12 volt DC solutions that will work quicker and easier than solar - for a lot less money.

A $300+ solar panel is VERY expensive! I could buy quite a few spare 18650 cells from AW for that money. I bought this for $35+freight and it can charge almost any rechargeable battery very quickly from any 12V source that can deliver enough amps. I use it at home from a PC power supply, but I could easily connect it to a car battery in an emergency.

Wait a sec: I just noticed that the solar panel you listed weight 10 pounds, geez that is equal to a large number of spare 18650 cells.