I have many Aqara Zigbee thermometers around my house and it's a pain to change the batteries once a year. Two AAA batteries should have much more capacity than CR2032 cell.

This case houses the sensor and two AAA batteries inside. It features plastic springs to keep pressure on battery contacts but it requires supports and following removal of the supports. 

Another option is to use integrated bridges instead of supports. I think it easier to remove bridges than supports.

You can select either version with bridges or enable supports in your slicer.

The assembly requires some wires and soldering to the battery contacts inside a sensor. I find it easier to just solder wires to the device instead of trying to fit a fake CR2032 adapter. 

It designed to be printed with 0.2mm layer height and without supports (version with integrated bridges).

There's a back cover with holes. I use it for attaching the thermometer to the wall by hot-gluing the back cover through the holes.

I've included .step files if anyone wants to modify it.