Tired of plugging in your kids battery powered vehicles each evening? It's hard to remember, and the toy never seems to be charged up when your kids want to ride it. Well, here's a simple solution. Their powerwheels will always be charged when they want to ride it, and you'll never have to drag out the charger again.

This hack cost me about $6 and took about 30 minutes.

Step 1: Supplies

You will need:

-a powerwheels or similar battery powered kid vehicle. I used this 6volt "baby injusa" quad.
-one or more solar cells, capable of powering the vehicles battery. I used 2 3volt solar cells from patio lanterns (wired together in series, to create 6 volts)
-some wire to connect the solar cells to eachother and to the battery ( I used speaker wire)
-a diode, to keep the battery from draining power back to the solar cells
-miscellaneous connectors to splice into the toys existing circuit (I used 2 scotch locks)

How it works:

The 2 solar panels are wired together in series to suck 6 volts of power from Mr. Sun. then they are spliced into the existing circuit, near the battery. A diode between the solar panels and the positive terminal of the battery ensures that electricity only flows in one direction (so that the solar panels won't drain the battery at night). Just park the toy near a window, and it will trickle charge the battery, directly from the sun...no more chargers!

Step 2: Drill Holes

Decide where your solar cells will mount. I stuck mine to the front fenders (you may find a better location). Choose a spot where they will get lots of light. Then drill holes so that you can fish the wires back to the battery compartment.

Step 3: Lengthen the Wires

My solar cells only had about an inch of wire attached to them - not enough to run back to the battery compartment. Do whatever you must to make them longer. I soldered about 12" of speaker wire to each cell. Then I covered up the connections with heat-shrinkable tubing, just to be tidy.

Step 4: Insert Solar Panels

once you've got long wires on your solar panels, and holes drilled, you're ready to start putting it all together. Fish the solar panel wires through the holes you drilled. Use some masking tape to temporarily hold the solar panels in place.

Step 5: Run Wires

Once the solar panels are in place, fish the wires through to the battery compartment. Route them so that they're not gonna get hung up on wheels or any moving parts. Hold them in place temporarily with masking tape.

Step 6: Splice Wires

If you're like me, you needed multiple solar panels to create enought volts to charge your battery. If this is the case, you'll want to hook your solar panels together in series.

Strip the end of the + wire from one solare panel and the - wire from the other. Connect them together. I soldered and heat-shrunk em to be tidy.

Step 7: Insert Diode

Okay, you're almost done. But before you connect your solar panels to the battery, you need to put a diode into the circuit. A diode is like a one-way gate that will make sure the solar panels only charge the battery; never drain it.

solder your diode to the end of the + wire. Make sure that the little white band is pointing towards the battery (and away from the solar panels). It's a good idea to cover up the diode, so that it doesn't short out on anything. I wrapped it in heat shrink tubing.

Step 8: Patch Into Battery

Now complete the circuit by hooking it up to the battery. I removed some plastic sheathing, and found the main wires to the battery. Then I just connected my + and - wires to the + and - wires of the battery. Scotch Lock connectors are a simple way to do this.

Step 9: Glue It Together

Okay, so there are endless ways you could do this. I chose to attach my wires and solar panels to the toy by "gluing" them. You could use screws, duct tape, whatever you want...

I stuck it all to the plastic body of the quad using some black silicon caulking i had lying around. It ain't pretty, but it worked.

Step 10: All Done!

That's it! Once the glue is dry, you are ready to use it. Just park it in front of a window for a day or so, and let the power of Mr. Sun charge your powerwheels up.