08-14-2017 03:17 PM
I have been monitoring the battery issues with the original and 2nd Generation Moto 360 for quite some time and I would like to help enlighten some folks on what is going on. I have evaluated and design batteries for tech companies and these types of problems are what I deal with normally.
Be prepared to throw out your watches after 9-15 months. The battery issues are not a design flaw for Motorola, but a lack of people's understanding of current technology. Battery life is not just how long the battery lasts, but also how many times you can recharge it. Manfucaturers warranty these items to last 1 year or less. The reason is that they are using specifactions provided to them from their vendors. Small rechargeable watch batteries manufacturers usually only guarantee 500 charges on the batteries. You will read numbers that say more, but I am assuring you, these small compact batteries are only rated for no more than this. Assuming you have to charge it every night, you waste 365 of those in the 1 year warranty of the watch. That leaves you with 135 charges to use for the times you need extra power on a busy day. As a Moto 360 owner myself, I can tell you that I always find myself happy to have wireless chargers nearby to ressurect my watch after a busy day of notifications, exercising, or false "Ok, Google" detections transcribing conversations with people I am talking to on my watch. I even put one in my car to get me back up and running in between my commutes if I need it.
So folks, when you are upset that your battery is dead within a year or less, understand you ARE getting what is techincally available now on the market. With the big uprise in wearable tech and Internet of Things, the small battery market is booming and everyone is buying as much as they can to sell the millions of products that we like to use. With demand high and supply low, the Quality Assurance limits of what's acceptable are opened up to not slow the production rates. Until we can have a fully sealed, rechargable and replaceable battery, smart watches will be a consumable item. Since having a slim watch is more important than having a good battery design, the major players will keep designing them like this to sell you new tech every 2 years and keep the cash flowing.
Technical Answer: Engineering folks, you will enjoy this
Lithim Rechargeable batteries are always a pleasure to study. If you can consider what products fit a circular watch for a maximum battery configuration, you need to come to the conclusion that a rechargeable Coin Cell is the best selection for your form/fit/function. Lithium cells are great because they can stay at a high enough voltage to operate the lower power devices and I/O directly before they hit their termination voltage and start to fail. Many of the good designs will set the termination voltages to be a hardware kill switch to prevent system failure from under-voltage situations.
Now being a good designed product with an Under-voltage application, only a few good battery experts can attest to the discharge curve variations of a battery over the number of cycles it faces. Near 70% of it's cycle life depleted, the response of a used battery and a new battery will perform differently. As the response changes, the gauge does not properly reflect the correct life of the battery. What you may see occuring more and more is that your device will turn off "while it still has X percent in it". This is the under voltage protection turning off the device and the battery hitting it's "termination" voltage. Similar to how car batteries are tested with loads to detect a worn or good battery, impedance testing and couloumb counting provides the gauges we are used to seeing on our devices. They do not learn to have less capacity over time so the percentage is out of the original new capacity. Patented battery software is a great field now and unfortunately many companies will not share their secret sauce to keep them better than the competitors.
Mechanically, batteries also change as well. Many people remember the cracking issues with the back of the moto 360. I was one of the few original folks who had it and I kept thinking it was because of my pebble band. I bought an oem metal moto360 and had cracking again. Then I started to study the teardowns of the moto360s and I found the problem. What I thought was me being rough, was just the strain of the battery flex from charging and thermal expansion of all the materials. I studied the stress points on the moto 360 back cover and I found everyones cracks were happening at the same weak points in the cover. If you identify the common tolerances for the materials they use to make these watches, it explains where the battery problems and cracking problems align from.
Water.... oh you love to kill Electronics. I will also put the disclaimer that the water resistance of the Moto360 also plays a factor in the performance of the battery and watch. When water leaks ino the watch after the nano-coating fades away, the inrush of current and the lack of protection can kill the life of the battery and the gauging electronics. Add the leak path from a cracked back case allowing very conductve sweat to leak in and viola, smart watch death.
So Motorola, rather than asking people to do a factory reset. Why not save some time and forward this chain off to some people in the engineering department who can understand it.......
08-14-2017 03:49 PM - edited 08-14-2017 04:34 PM
I genuinely appreciate your explanation. But based on your explanation above, shouldn't we get a low battery indicator before it goes dead? Many of the watches, including mine, are turning off with no warning and showing 80, 50, 25%, etc. charge. It also doesn't explain that almost everyone saw defective perfomance almost immediately after the v2.0 update. Mine, in fact, improved after a recent update, where the turning off started to happen at 25% instead of prior turn-off level of 50%. Thank in advance for all of your time on this.
08-14-2017 04:01 PM
I have 2 Moto 360 first gen watches. My own and my son's. Both have been used almost daily since they launched years ago. We have no issues at all with our batteries so far. I just came home after 10 hours and still had above 70% left. Maybe we're lucky. Also his does have cracks in the back. But water hasn't gotten in even with washing hands. Mine has no cracks. I also have a much bigger wrist, which I think helps stop the cracks since it cracks near the mounting of the bands as if a smaller wrist is a cause. So I don't think the battery should go so early. But this is my own experience and I'm sure others have had different ones. Thanks for the post.
08-15-2017 07:24 AM
Thank you all for your comments. Here's some more information to help clarify:
As far as "It should turn off sooner" that is incorrect due to the way battery gauges and coulomb counting works. Since the battery is not removeable it is very easy for the battery gauges to monitor the power in and the power out of the battery since the chips that monitor it are directly connected to the rechargeable battery. When the watch "dies" it is because it is told to turn off the processor from a hardware limit or it has observed that too much power has been consumed out of the battery where it actualy is dead..
So let me talk a little more techincal for it. The battery gauge in the moto 360 is the Texas Instruments bq51051. (TI loves to sell battery gauges, but not support them). It has a termination sense circuit that is used to turn off the battery when it is "depleted". That sense circuit does not adapt to the life of the battery but to a hardware preset that was designed for the original life of the battery.
Let me answer the next comment I know that is coming: "How does it work for me after so long?"
This question is the key to why battery management and usage is so important. The discharge rate (how you use it) and the charge rate (what you use to charge it) is CRUCIAL to the longevity of the battery.
Exercise is great for the body, it is also great for batteries. If you only exercise for 5 minutes a day and you sleep for 10 hours you will feel lazy and sluggish because you're not exercising enough. This lack of exercise will let you last forever, but when you need to run hard, you won't be able to do it. The flip side is if you exercise all day and sleep for 2 hours you won't be able to keep it up for long and will soon not be able to perform like that anymore. Batteries want the middle ground like human bodies do.
If you use your watch at the ideal discharge rate for the battery (i.e any combination of no Wifi, no GPS, limited heart rate, limited notification, low brightness, and always-on set to off), you can extend the life of the battery. Most users want at least 70% of that functionality. If you had to size a battery to maintain the discharge and life, I would expect us all to have a big brick on our wrists.
The charge rate is also crucial to the users experience. I am always happy to know I can quickly recharge my watch to keep it on for the rest of the day. If you told me I had to charge my watch for 5 hours after it was dead, I probably wouldn't use it.
This drive for user experience is the essence of how watch companies want to keep selling newer tech and hope that we dump our watches after 1-2 years. The battery abuse is the reason why we are complaining now and they quit making more of them to not have to deal with it.
08-16-2017 07:33 AM
Just wondering - I've seen battery recondtion apps for phones. Do they work and increase performance and/or overall life? Seems like an app for the watches would be a good thing, but I couldn't find one in Playstore.
01-19-2018 09:24 AM
I have suspected that the 2.0 update and the Lenovo software update has had something to do with the number of sudden poor or dead battery issues on the Moto 360 2nd gen watch. With the high number of people experiencing this issue back in October of 2017 certainly gave room for pause before applying the problem to the battery. I pressed on with my watch recharging it three to four times a day trying to squeeze some more life out of it. Then, lo and behold the battery drain problem miraculously disappeared last week, the 2nd week of January 2018. I am now getting better battery life than I did before the 2.0 update was rolled out, with about 30% to 40% of power left at the end of a full day. So my question is, do I have a born-again battery or was this whole issue related to the Lenovo software issue rollout? Hmmmmm! I would invite everyone who shelved their Moto 360 2nd gen watches to take them back out and recharge them to see if you too will have this sudden born-again experience? If so, then, like me who went out and purchased another smartwatch vowing to never buy another Moto 360 watch again, will we ever again be able to trust Lenovo to do right by their customers? By the way, I just received an update to my watch allowing the Bluetooth to operate on a stand-alone basis. Bye the way, I have always suspected that the battery drain issue was related to the wifi and Bluetooth interface. Will there be a mea-cupla from Lenovo? I doubt it.
01-26-2018 12:26 PM
Let me explain my own experience with this issue, after trying what's suggested on multiple web sites/forums (full reset, unistall and re-install android wear app, etc...) the issue persisted, until one day I decide to pair my watch to my work phone (iphone) and at the end of the day I still had 50+% battery. I thought the issue may be my android phone then (turbo 2), but, how can I fix that? I didn't want to reset my phone so I cleared all the bluetooth data only, re-connected my watch to my phone and the issue was gone. NOTE: I am trying to use google fit app instead of moto body, denied any permisions to moto body and fully enable google fit, my watch seems to work smoother, I hope my experience helps some of you.