[Moto Z Guides, News, & Discussion] doujinsinner:
I think most of us had heard that Moto Z has a erratic/bizarrre/high batery drain in one or another way.

For my case it's a broken battery and i think it affect entire battery lots but Moto never accept and recall its.

I will share my experience.

According to this topic https://forums.lenovo.com/t5/Moto-Z/Moto-Z-extreme-battery-drain-after-7-1-1-update/td-p/3758100.

There is 100+ pages and numerous people affect by this issue around the world.

Me live Thailand. My Moto Z model is XT1650-03, Dual SIM.

I bought a second hand phone. It's come with Nougat 7.1.1

My previous phone is Xiaomi Mi4C that has a SOT around 3-4 hour [with 3000 mAh]

So when i got Moto Z. SOT is aound 3-4 hours. with 2600 mAh I think it normal. [My use is texting LINE, internet, on WIFI most of the time]

After 2 month I got update to Oreo.

I notice battery is drop fast than normal. I use better batery stat and waklock detector to nail down the cause.

But all is normal. Phone is almost in deep sleep. when use battery is drain aound 4-5%/Hr or more.

Then i start to google and found above topic and similar in another website.

Moto web moderator usuallly suggest these method

1. If happen after update please clear cache through Recovery

2. Do a baterry calibration [force restart then use turbo power supply to chardge till 100%, leave it overnight]

3. If above fail do a factory rest.

I try method 1. and fail

When use method 2 . It notice a weired battery percentage

- before force restart no matter % of battery when restart % will suddenly drop [e.g. 85-->45, 90-->2]

- this make me more curious

- after charge with turbo power adaptor to 100% and leave overnight. I try to force restart again. guess what the battery % is suddenly drop again .

- after try many time i come to conclude that "IT'S NOT A SOFTWARE. IT'S A HEARWARE ISSUE"

I go to Moto service center and tell them abou tthis battey drain.

They smile and said that "This happen frequenly. It's a battery defect"

My phone still under warranty so it's free.

FYI : if out of warranty cost is around 40$ [PS. In thailand] not too pricy for battey+labor cost [this phone is hardly to replace battery by yourself]

With new battery Moto Z is a monster in SOT. I got SOT 4 Hrs. with remain 45 % battery. With my usage i think 7-8 Hrs. is possible.

To sum up

Those who face a erratic/bizarrre/high batery drain.

Please try to do battery calibration first. But if you find suddenly drop in battery % after force restart. It's a broken battery.

Go to Moto service center ASAP.

No software update can fix this.

For 7.1.1 update that emerg this issue.

In my humble opinion i think no software can do damage to battery. In worst case, poor sotware will cuase huge waklock and baterry drain but not suddenly drop after restart.

It's maybe coincidence that this 7.1.1 update come out around the time that defect battery show the sign.

For further battery save up.

I found that in Oreo. without Root we can limit background activity.[this look like function in MIUI rom]

App that optimize for Oreo doesn't has this function.

So it's for old gen app that developer didn't update their code.

[e.g. LINE , XDA labs, Pinterest, Google play service, Google pay store]

Visit these website for How to with picture

http://visihow.com/Manage_Battery_Performance_on_Android_Oreo

https://www.howtogeek.com/324566/how-to-limit-background-activity-for-apps-in-android-oreo/