I wanted to be able to use my Ridgid 18v batteries in other projects, and I found Simhopp's model. However, I didn't want to have to buy the actually battery connector part.
So, I reverse engineered the connector, using contacts from an electrical socket (US style) that are glued in. I modified the adapter plate so that it would be flat where the battery connector can be superglued on in position.
Solder wires onto the contacts before gluing them to the battery connector body.
Dry fit the parts onto a battery, and sand them down if necessary. If there are any gaps to fill, apply superglue and sprinkle in baking soda.
Ridgid_battery_mount_2 is an edit of the battery mount that adds screw holes and removes some material. This is suitable to make a battery holding rack by attaching several of these to scrap wood or your workbench or whatever.