Dexcom G4 / G5 Battery Cap for original and LR44/357 size batteries

thingiverse

For many people using the Dexcom G4/G5 CGM, replacing batteries can be a costly hassle. This battery cap makes it easy to safely swap out old batteries and reuse the transmitter without breaking the bank. The battery cap is designed to fit on a transmitter that's been modified with a belt sander. First, sand down the transmitter casing until both battery tops are completely exposed - you can remove the top battery tab if needed. Pry out the old batteries carefully, taking care not to break the welded tab underneath. Use a razor blade or similar tool to pry off the tab from the old battery. Once removed, chip away at the sidewall where the vertical tabs exit the plastic on top. Fold in the corners of the vertical tab so they make contact with the side of the new battery casing. Insert new batteries (original size or LR44/NiMh) or 357/silver oxide - recommended). Fit the cap onto the transmitter by hooking the front portion and pressing the rear section firmly into place. This may require a bit of force. You can add sealant under the cap for watertight operation, but since it's been modified, there's no guarantee. It's best to remove the transmitter during activities where it might get wet. Test the voltage across the 2 small metallic terminals at the bottom - it should read 0.02v. Bind the transmitter and you're good to go!