Battery drain on Version 2.68

My watch died this morning, I have a stationary watch now. :) works only when connected to charger. It is not even funny for a watch for this price. Never again buying garmin 

I have Venu SQ 2 Music and it was working excellent for more than 2 years, mostly used as a fitness watch, sometimes listening music. Few weeks ago I noticed heavier than usual battery drain, but it' shard to say exactly when and what happened. I think I had autoupdate firmware disabled (after incident of some older firmware not allowed to install apps).

Updating firmware from 2.66 to 2.68 didn't solve the problem. Currently my watch does not work unless connected to the charger. I've tried all sort of resets, leaving on charger overnight, playing with setting.

My overall assumtioons are - something made watch to deal with battery abnormally which lead to incorrect charging/discharging cycles, which most likely killed the battery. When connecting to power it is showing 100% charge, but after opening watch multimeter is showing 2.82V only which is less than 3.87V listed on battery.

I plan to replace the battery and see if it's something in firmware/hardware acting abnormally. Until then I don't have certain conclusions.

BTW, the battery details are:

Model: 361-00136-20

Rechargable Li-ion Battery 1|CP3/21/26

Voltage: 3.87V

Rated Capacity: 205mAh/0.793Wh

Manufacturer: Springpower Technology (Shenzhen) Co.,Ltd.

There is a new battery in my SQ2 as of yesterday. The case is not glued back together yet so I have not been wearing the watch yet, but today the charge is still indicating 97%.

Description of battery: New High quality 361-00136-21 205mAh 361-00136-10 Battery For Garmin Venus SQ Venu SQ Music Watch + Free Tools.

I assume either there was a battery charging/discharging issue with the Garmin software and/or possibly the battery was inferior.  Again, these are unproven assumptions.  However, how can I have a Fitbit Versa 1 (2018 era) that still works yet the Venu SQ2 did not even last 2 years?

Thank you for posting, that's reassuring! Hope your battery work well and long!

I'm still waiting for the battery delivery, may take few weeks. Tried to re-solder the old one after noticing its voltage went up to 3V+ at some point but it didn't help, seems it's not willing to charge, so have to wait for a new battery.

Speaking of Fitbit, I had two charge 3 copies, and they both died after almost 3y of use. One due to screen issues, another due to the similar battery degradation observable with Venu SQ 2. I'm assuming that it can be just something wrong with batteries when firmware overusing them abnormally, leading to rapid battery death. It may, or may not be related to firmware updates, but with Fitbit charge 3 battery problem happened same day firmware got updated - it was holding for a week and after firmware update just died. I moved good screen from it to my first broken one and it worked, but after firmware update - died next day...

I'm taking a little time to give you a little technical feedback that may help you.

At the time of the last update (since 2.66), I found the battery capacity to be in sharp decline, even though in terms of settings, I don't deprive myself. All GPS available, unlimited measurement sensor, animated watch screen, etc.

Anyway, I had a look at the Garmin forum, and I saw a lot of comments like mine, and one Internet user indicating that he had found the origin of this new greediness of the watch.

In fact, the touchscreen sensor update is to blame. If you want to keep a good battery life, the watch should be configured as follows:
- Settings -> System -> Auto Lock = Always

I hope I'm not mistaken, as I made the setting some time ago.

Perhaps the sensor is more sensitive to respond better with certain people.
When the setting is made, the watch face always appears when you turn your wrist or “double tap” the screen.
However, when you try to access the menus, the padlock appears. Hold down the top button for a few seconds and the padlock will unlock. You can now navigate through the menus. The lock automatically resets itself in a few seconds, with no need for further manipulation.

The watch's autonomy is much improved with this setting, even if the ergonomics are a little less user-friendly. (you have to unlock the padlock to access the menus).

(Translated with DeepL from my post on a french forum.)

Received genuine battery replacement today (it was delayed shipment) and soldered in. So far watches working after charging from 17% to 100%. The old battery is swollen almost 2 times comparing to flat new battery shape.

Though after 3 hours watches were keep showing 100% battery so performed factory reset, now I see 98% charge which is reassuring. Will keep using watches for few days, if all is good will seal the screen cap.

Update: Since the first charge from 17% to 100% and factory reset, watch is working great with replaced battery. It is showing 52% so far. It was not used for anything extensively like GPS or Music, simply checking time/weather and fitness data periodically. I decided to seal watch using soft removable glue, just in case need to open it again.

I didn't set any extra Auto Lock, keep operating with same settings/watchfaces as last year. It doesn't seem that firmware 2.68 doing anything wrong to watch, battery consumption remains extremely low with most default settings (display timeout time is set to Long, brightness: Medium).

So far I'm happy about decision not to ship watch to Garmin for another used copy replacement which would cost ~$150, and who knows how long another used battery would operate. 

Instead, paying just $20 for brand new genuine battery and DIY replacing it, resulted in great working watch that should hopefully serve well for another few years.

How easy was it to open the watch and replace the battery?  

Good question. It's definitely not a trivial operation and requires fine disassembly skills and micro-soldering of battery wires, I'd recommend to check few relevant YT videos by searching "Garmin Venu SQ battery replacement".

Personally I used sharp plastic scraper tool by gradually pressing it in from both strap connection areas, pruning screen module apart. It's important to lift screen gently to not damage ribbon cable. Both ribbon connectors have no lock, just need to be accurate on centering when re-connecting. Battery is secured strong with double-side adhesive tape, I used very thin metal pruning tool to slide it between board and battery to safely break the tape and detach battery - make sure not to bend board or accidentally deform/puncture battery. Beware of tiny electronic elements on board surrounding battery to not push on them.