This project has become part of the Stay-At-Home remote learning for my daughter. She's in 1st grade and has an Engineering class. Their remote learning assignment is Tinkering at Home. So we decided to rewire her Power Wheels Mustang. We needed an adapter for these batteries since I already have a bunch of them for my tools. The original 12 volt 9.5 AH Power Wheels battery takes too long to charge (18 Hours). We get just about the same run time on (2) 20 volt 4 AH batteries wired in parallel and it only takes about 20 mins per battery to charge. I have a motor speed controller installed in the car to limit how fast it can go, but lets face it... Its always set to full speed. haha. My daughter loves it.

This is a battery adapter for a Craftsman V20 Battery. I was inspired by Griffin175's battery adapter (https://www.thingiverse.com/thing:3127879). I designed this adapter to not use any hardware to hold the contacts in place or the need to use glue for the top cover. I use the same 1/2" copper pipe straps Griffin175 used for the contacts. You can find them at any hardware store. I'm using 14 gauge wire on this project. 12 gauge wire may fit out the slots in the rear also, but I'm not sure.

Instructions for the battery contacts:

• Hammer one of the copper pipe strap flat and then cut it in half.
• Measure in 10mm from the side with the hole and then bend it 90 degrees like shown in the pictures above. I clamped them side by side together into my vise and used a hammer to bend them at the same time so they would be the same.
• Strip about 8-10mm of the insulation from the wires solder them in place next to the hole so the wire can bend down enough to exit out the back of the adapter.
• Insert the contact in place and slide the cover over the top.
• All done.

I can modify the design or upload my Fusion 360 file if someone wants to use larger wire or modify it for their needs. Just a warning... I'm fairly new to Fusion 360 and pretty sure I didn't model this the most efficent way.

The next Power Wheels project will be lights and a real car audio stereo with a couple of speakers.