The last big question on the G6 is “Can you replace the G6’s transmitter battery?”
Happy to report that you can, indeed!
I don’t have any fancy videos of it yet, because I was just focused on making sure I could do it vs. document it well on video. I have replaced loads of G5 transmitter batteries using the guidance on this great video. The same basics applied to the G6 transmitter work too…grinding down the grey plastic/epoxy, peel up the top tab carefully, and then pop the battery out.
However, I didn’t find the G6 quite as easy to replace the battery as with the G5. It’s definitely doable, and I’d get better with practice.
Here’s the note-worthy differences and things I learned:
The G6 only has one battery, not two. And the battery is accessed from the underside of the transmitter, as opposed to the top like the G4/G5 transmitters
The battery that the G6 uses is also quite a bit bigger than the G5. If you want to order replacement batteries for the G6, here’s a link for a set on Amazon. They are Maxell CR1632 3V lithium batteries.
The other major difference is that the battery (1) goes closer to the edge of the transmitter and (2) there are little wings to help the transmitter lock down inside the sensor. Both of those combined to make it just a little bit more difficult to do the grinding down to expose the battery.
Here’s a picture mid-grind:
While you are grinding, you have to make sure not to go too low on the corners above the little locking wing indents.
You also have to be aware that the top tab on the battery has a different dimension than the G4/G5 transmitters. The tab is much skinnier and has a few weak points built in…presumably to make the tab much harder to successfully bend up without breaking it. There are three weak points that I could see.
Therefore, I was trying to be especially careful on that edge-located weak point as I ground down. I did at first manage to get the 2/3 tab up just fine at first. But, in removing the battery next, I ended up losing the long end of the tab (it broke at the middle weak point pretty easily). The next time I do this, I will work harder to remove more epoxy around the edge weak point more carefully…will probably let me remove battery easier (see dicussion below) and maybe keep more of the tab. It’s going to be a balance though, too much grinding and you’ll take the whole tab off at the edge weak point. Based on the teardown pic though, probably salvagable if you did.
Battery removal was the hardest part. I think it’s really important to get as much of a clean edge around the battery as possible. Since the battery was much bigger than the G5 batteries, I found it was actually a lot harder to get leverage going to pop out the transmitter. There was a lot more resistance to popping out than on the G5. Possibly because I was too conservative on getting clean edge at first (definitely a contributor, I think)? Or maybe because I wasn’t using a longer lever to start? I don’t know…but eventually I did have to get out some vice grips and that made all the difference. Since I was able to hold the transmitter more forcefully, I could apply a better pressure. Worked SO well though, that it just popped super hard and fast. Oops. Did that little tab that normally sits under a battery go flying across my laundry room? Could have. I won’t know for sure until other people get a chance to open up their transmitters over the next few months. 😉
This is what it looked like when the battery was finally totally removed; a slightly shorter top tab (but still strong and in good shape) and a questionable bottom.
I assumed that there must have been a contact tab underneath that went flying. So, I ground out a little on the bottom to expose the contacts and put a little bit of solder down. Once I got that done, new battery was laid in and tab bent down to make contact on top again. I did use a touch of super glue to hold the top tab down, just to be sure.
And voila…it works. A G6 with a replaced battery. I sealed it back up with two-part epoxy and the transmitter is working well again.
Don’t forget to use the reset transmitter app to be able to use the official Dexcom apps after a battery replacement.