After watching Shawn Blaszak of PS:one demonstrate solar charging a tv remote I was inspired to do something similar with my wiimotes.http://vimeo.com/21704047
I'd recommend watching the video before reading the rest of this.Materials :
Solar cells - I used 2x 3v 50mA for each remote
Rechargeable battery - A couple of AA type would work but I had a wiimote one with connections on the outside.
Diode - 100mA
Paper-clips or sturdy wire
Step 1: Plan
I wasn't sure if flexible solar cells could handle the kind of abuse wiimotes get so I'm using a dock and a rechargable battery pack I had already.
It may have been easier to add the solar panels to a bought usb charging dock, you get a good fit for the remote and won't have to spend ages getting the connectors to match.
The wii mote is D shaped, I don't have a router so to cut this so I used a power drill. For each wiimote socket I drilled three holes, the first two are 5mm with centres 15.5mm horizontal 12.5mm vertical from the centre of the 40mm centre to give edges as marked. The circle shaped gap allowed the cord to pass under the wiimote.
Note: I used soft pine and the 40mm spade bit went through it fine, However the two 5mm holes on the edge could well catch your 40mm bit so have care.
Check you socket against the wiimote, I needed a minute or two with a chisel to flatten a few edges.
In keeping with the wii I painted it white.
Step 2: Panels
For each wiimote i had 2x 3v 50mA cells connected in parallel, These were mounted on a PVC pipe in a manner to allow me to twist the pipe. The windowsill would get the most light but isn't always convenient so sometimes I want rear facing panels and sometimes front.
Pairs of panels were soldered with a diode the to white (+) wire this should stop the battery discharging through the panel but allow the panels to charge the battery.
Step 3: Contact
Initially I liked a "brush" connection like a scalectrix. I spent far too long trying to get the "perfect" connectors when really all i needed was some which work and can be improved later. In the end bent bits of wire were fine, the wire was looped around the nose of some pliers and slightly sprung so as to give a good contact. I imagine they'll need a bit of adjusting over time, and one day I may get some wire wool or scalectrix brushes.
Step 4: Finished!
A quick test with the meter shows I get a trickle charge on a fair day!
When both panels output their maximum 50mA a 1200mAh battery will take about 12 hours to charge. However if I'm reading the meter right and this is about 0.8mA.
This means 1200mAhr batteries will take only 125 days to charge! (assuming 12hrs sun a day).
When summer comes I hope it'll be better, this window has great summer sun in the morning but the low winter sun is blocked by houses over the street. If that doesn't work I'll put all four panels onto one wii mote. Or eight panels..