Solar phone charger in a bottle.
The time has come. Drink a peppy beverage of your choice, or drown your sorrows by draining a bottle of Johnnie -- do whatever it takes to get an empty bottle. And then follow these easy steps to transform it into a solar phone charger.
Time to complete: an hour
A wee bit of soldering required
Difficulty level: Pretty easy, but broken glass is likely
Number of band-aids required: 1-2
This is the 5th entry in the Solar Pocket Series of projects that Alex (this guy) and I are posting over the coming weeks. For more about Solar Pocket Factories and DIY solar check out our just launched Kickstarter campaign (Aug 15 - Sept 14): http://www.kickstarter.com/projects/alex9000/the-solar-pocket-factory-an-invention-adventure
Here's what it's all about in 2 minutes:
Step 1: What you need
++ Either a hand of steel for popping the bottom out of the bottle, or a glass cutting wheel.
++ A playing card.
++ Copper tape (single-sided adhesive): This is easy to find at most hardware or electronics shops.
++ 11 solettes: these are small pieces of monocrystalline or polycrystalline PV silicon that are typically hidden under an epoxy blob in off-the-shelf panels. You need the raw stuff for this instructable. Available a few places on eBay or via our Kickstarter page here: http://www.kickstarter.com/projects/alex9000/the-solar-pocket-factory-an-invention-adventure
++ High temperature superglue aka cyano: the thin stuff, like crazy glue. The gels don't work well. The off-the-shelf super glues will work, but for a more reliable panel you will need high temperature cyano, since most basic cyanos breakdown at 80 degrees C (which is a bit on the threshold of what your panel could experience in a bottle sitting on your porch). I used Aron Alpha 401XZ, which gets to 120C.
++ Soldering iron and solder for just a couple joints.
++ JST connector with a couple free leads.
++ USB cable, plug to receptacle.
++ Lithium battery; I used a 2000mAh LiPo.
++ A lithium charge chip or board. There are several of these on the market, and they are also available in the phone charging kit on the Solar Pocket Kickstarter page mentioned above. I use the Seeed Studio LiPo Rider Pro for this charging bottle.
++ You don't need to encapsulate your panel for this project, since the panel will be protected more or less in a bottle. Although you will get corrosion over time at the solder joints, it will operate for quite a while without any encapsulant as long as your bottle doesn't get filled with water. However, you can encapsulate with 5-minute epoxy, but note that epoxy is only good for 2 years in the sun. Better encapsulants are PU designed for doming and high-end solar applications (like solar cars); and another great method is EVA laminate with glass. More on this method on a separate instructable shortly.