Mi Mix 2 Battery Degrading After 8 Months


Weltraumjunge

Members
Oct 11, 2017
14
13
Hey fellow Mix 2 users.

I bought the Mi Mix 2 at the end of September 2017. Now, approximately 8 months later I noticed the battery life to be unexpectedly short for 1 week.

Yesterday I installed AccuBattery, an app measuring battery related data which tries to calculate the real battery capacity.

See the Screenshot. After only 8 months of average use the capacity is down from 3400mah to about 2500mah. That's less than 80% capacity left.

Does anyone have a similar experience already?
Sent from my MIX 2 using Tapatalk

 
Last edited:

cobben

Members
Dec 2, 2017
887
82
Hey fellow Mix 2 users.

I bought the Mi Mix 2 at the end of September 2017. Now, approximately 8 months later I noticed the battery life to be unexpectedly short for 1 week.

Yesterday I installed AccuBattery, an app measuring battery related data which tries to calculate the real battery capacity.

See the Screenshot. After only 8 months of average use the capacity is down from 3400mah to about 2500mah. That's less than 80% capacity left.

Does anyone have a similar experience already?
Sent from my MIX 2 using Tapatalk
You have to let Accubattery run over a number of normal charging cycles to get a reasonable read on the battery condition.

I bought a one year old Mi Max1 Prime last fall that seems to have about 82% of its original battery capacity left. That may well be normal for a year old phone that has been in steady use.

The phone works fine, no problems so far.
 

Drnizeguy

Members
Dec 3, 2017
4
13
I noticed it too, but....

The app calculates the mAh wrong.

Check this topic on XDA: forum.xda-developers.com/mi-mix-2/help/beware-2700mah-battery-t3741672/page3

[...]
Taking the nominal voltage of the Mi Mix 2 which is 3,85V and the USB voltage which is 5V, you get a factor of 1,3. Now let's take the average result you guys got from your meters, around 2750mAh (quickcharge readings don't count here, they work with up to 20V which further manipulates the outcome). So 2750mAh would mean: 2750*1,3=3575 which results in a 3,85V capacity of 3575mAh
[...]
 

Weltraumjunge

Members
Oct 11, 2017
14
13
The app calculates the mAh wrong.
Check this topic on XDA: forum.xda-developers.com/mi-mix-2/help/beware-2700mah-battery-t3741672/page3
Sadly, I don't have a way to compare to hardware readings right now. I wrote an e-mail to the developer to check whether the app takes different charging voltages into account.

You have to let Accubattery run over a number of normal charging cycles to get a reasonable read on the battery condition.
I'm gonna keep an eye on it to see how the value changes over the next week.
 

cobben

Members
Dec 2, 2017
887
82
Sadly, I don't have a way to compare to hardware readings right now. I wrote an e-mail to the developer to check whether the app takes different charging voltages into account.


I'm gonna keep an eye on it to see how the value changes over the next week.
I ran this app at the same time on two new phones, Mi Mix & Mi Note 3.
It gave the correct value for the batteries on those.
But if you run the app while you are using the phone as a hot spot, it may show a poorer value than otherwise.
 

Weltraumjunge

Members
Oct 11, 2017
14
13
Hi,

Thank you for your email. The phone's charge controller converts the voltage to whatever the battery accepts so it doesn't matter what the charger outputs (5V/9V/12V/15V/etc.). We only check what the current mA is that goes into the battery and track that so it won't be influenced by the charger's voltage. For calculating capacity our recommended method is via the manual benchmark: (link removed)
Kind regards,

Chad
I wrote to the developer and got this answer. So supposedly it should not calculate the wrong capacity. However, I followed the guide for a manual benchmark he provided.

The new measurement I got is still concerning but less drastic. From 1-100% the app measures about 2900mAh which translates to about 85% of 3400mAh design capacity.


Sent from my MIX 2 using Tapatalk
 

ovisoftblue

Members
Jun 5, 2019
1
3
Did you try using Chargie? It's a phone charge limiter that interrupts power at your chosen charge level, automatically, during the night. I've been using it for the past 7 months on my Poco F1 and it still goes all the way up to 4000mAh per cycle. Just google it. Chargie dot org.