Mine is 4 months old and makes it 48 hours max after a charge to the time it gives a low battery alarm. This is with only charging it when it has one bar flashing (which is what Dexcom people recommended) and leaving it to charge for three hours (I time it). It was making it 75 hours or so when new.
I get about 3-4 days for the alarm to come on. It’s got about 8-10 before it shuts off once the alarm starts. Mine is about 1 year old now, but I haven’t noticed any difference in battery life yet.
I can usually go about 72hrs until I notice the 'empty battery' message flashing on the screen. I have a hard time not recharging it before I get to that point because I don't enjoy being out and about with a dead Dex.
Do you have alarms going off often? What are your alert levels set at? Do you use the "Out of Range" alarm? How often are you checking the screen per day?
Please don't feel as though you need to answer all/any of these questions. I'm thinking that if Dex is alarming/being checked/ etc often, the battery may not last as long.
That being said, I don't think you should change your habits or range just because Dex won't stay charged as long as you'd like (unless of course you'd rather just have a Dex that stays charged longer).
best,
~a.willie
It depends on how much I am looking at it. The more I view it, the quicker the battery drains, but we seem to get at least 2 days. I try to make a habit of plugging it in overnight even though that’s opposed to DexCom’s recommendation. I was told the reason that is discouraged is because it decreases the range of reception. I just down have any other time of the day when Caleb sits still and the nighttime range has yet to pose a problem.
I usually get 3 days or so from mine. I don’t remember having any problems when my original receiver reached the end of its waranteed life (12 months). I used my original receiver for about 14-1/2 months before I replaced it, even though the replacement was fully covered by insurance. I was putting it off because there is no way to combine the results of multiple receivers in DM3. I like the Success Report comparing two quarters, so that means I can only run it 6 months out of 12.
Mine is 15 months old. I charge the receiver overnight when I get to the one bar level. Normally I get about 3 days to a full charge. One issue. I set my high alert on the low side for me. So the vibration alarm goes off more often. That shortens the time until I need to recharge.
aaronm
My battery life seems to be getting shorter lately. I am at 2 years with this receiver now. What I’ve found is that it will go from 3 bars to a blinking one bar without much time in between (ie not a long time at 2 bars). My receiver is probably getting ready to be retired…it shows its 2 years of service…but I really wish I was replacing it with something smaller.
I think I get 3-5 days out of mine. I do look at it a lot. Once I see 2 bars I even charge it as I never know where I’ll be once it goes down to 1 bar and dont feel comfy with going down to 1 bar. So overall it gets charged once a week
Once my Dexcom receiver battery fails to charge, I plan on disecting the receiver to see if the battery can be replaced. Since the system is now 15 months old, the warranty is passed. Mine is not covered by insurance, so I have nothing to loose. When the battery in my Garmin GPS failed I found kits that included tools and a replacement battery. It took me 20 mins to replace the battery and the unit works just fine. I don't expect to find a Dexcom kit, but I do expect to find a standard industrial battery soldered into the circuit.
aaronm
I get about 48 hours out of mine but I have my alarms set at 70 & 120 and I am also always hitting the button to see what my BS is. If the alarms go off at night, I tend to sleep thru them so that doesn’t help battery wise.
Depends on how often you use it as a flashlight when heading to the bathroom in the middle of the night 
LOL! I am so glad I am not the only one who does this hehe
Ha! So true! I just bought a "cell-a-bright" LED light meant for a cell phone. I'll see how well this works... Only $2.50 on ebay.
I've never had it go dead- I carry the charger with me.
The alarms go off a few times per day. I reset the alert levels all the time. I use the Out of Range Alarm but it almost never goes off. I check the screen at least a hundred times a day.
Make sure you post and let us know what happens, I have no insurance coverage CGMS wise either.
Smart idea. The Receiver battery is probably Lithium thin-film, no problem. Do keep in mind, though that the non-rechargeable transmitter battery, in carefully sealed plastic, is possibly one of those "ultra-high energy density" batteries used in satellite and space technology; the chemicals might be very dangerous.
Some of them aren't terribly difficult, but others can only be transported by truckers with very special HazMat certifications and equipment. (Basically, the companies and drivers who are allowed to drive Nuclear fuel rods around.) DON'T go digging into the Transmitter!
Mine lasts about 4+ days.
I charge my battery every night.
Once I tried to test the longevity and did not charge it. On the fourth day, it still showed 3 bars. Then all of a sudden, in the middle of the day, the alarm sounded and it was dead within a short time.
Never saw two bars, or one bar.