I purchased a new ryobi tool without a battery. I didn't want to purchase more batteries and I had an old laptop charger (18v) lying around in my junkbox, so I designed this adapter. For the battery contacts you need to fold some metal or copper, just something to solder on. Be inventive.

Original ryobi adapter model is from: https://www.thingiverse.com/thing:1677812 so this is kind of remix from that.

PSU is attached with zip-ties to the adapter.