This has been a project I’ve thought about a lot over the year of owning my car. Now that I’ve got a 3D printer and the knowledge on how to effectively model and create something that fits my fob, I can get to making this a reality.

Someone has already fit an Airtag into the Keyfob of a Tesla, and while my key has less internal space, I think I can overcome that with some creative handiwork, silicone, fishtape, and maybe a little soldering.

Update #1:

As a baseline, I have recreated the fob in fusion and modified it so a significantly larger battery can fit in. Now, a 2032 battery can easily fit into the fob, allowing for 2x the battery life of the OEM fob. I have also increased the overall height by 1mm, while increasing the usable height in the recess by 1.5mm. This should be just enough to fit an AirTag.