Hygrometer Case for AA or AAA Battery

Hygrometer Case for AA or AAA Battery

✨ Now even smaller! ✨

These cases for a popular mini-hygrometer are designed to hold a long-lasting AA or AAA battery instead of its supplied button cell batteries.

Compared to the two supplied LP44 cells in parallel, a single 1.5v AA battery should last a couple decades before it needs replacement and it'll be easier to replace when it does run out.

Instructions

These cases print face-down without any supports required.

You'll Need 

• One AA or AAA battery
• Positive and negative battery terminals (13.5mm × 11mm)
  (These can be found inexpensively on Ali Express)
• ~10cm of electrical wire
• A soldering iron or some electrical tape
• Flush cutters (optional)

Installation

1. Solder (or use electrical tape to tightly wrap) the “springy” battery terminal A to the centre of button terminal B, and the “bumpy” terminal C to the edge of button terminal D.
   
   
    
2. Using flush cutters, optionally cut small wedges in the plastic battery cover (circled in green) so the wires can poke through. If you don't want to do this, you can leave the cover off entirely.
    
3. Push the case with the wires through the front of the hole until it snaps in place.
   
4. Tuck the wires into the grooves, and fold the new battery terminals over the sides of the battery compartment.
   
    
5. That's it! Enjoy your ridiculously long-lasting hygrometer!