The Nintendo DS Lite seems like it was made to have solar cells put on it. It has a large amount of surface area on the top and bottom that both face upward when the DS is opened. The top and bottom faces each have exactly the right amount of room for two 60x60mm solar cells side by side. Each one has a maximum power output of 3 volts at 40 ma. The top two are connected in series and so are the bottom two. These two sets are wired in parallel to get a total of 6 volts at 80 ma, perfect for trickle-charging the battery.
Solder two of the solar cells together to make a panel, with the negative strip connecting to the positive strip. The negative ends of the solar cells have a skinny black mark by them. Repeat this with the other two to make another panel.
A diode is an electrical component that allows electricity to flow in one direction only. In this case, it is used so that the solar panels can charge the battery but the battery can’t discharge into the solar panels. On the positive end of one of the panels, solder the anode (the end without the white stripe) of one of the diodes to the positive end of one of the solar panels so that the diode points down. Solder the anode of the other diode to the other panel so that it points up. After that, use a dab of hot glue to secure the diode to the solar cell.
Cut a length of wire about 15 cm long. Strip one end and solder it to the end of the diode on the top panel (where the diode faces down). bend it at the corner of the panel, then tape it along the edge of the first cell.
Cut another length of wire about 15 cm long. Strip one end of it and solder it to the negative side of the top panel. Bend it around the corner and tape it.
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