[Xiaomi Mi 9 Guides, News, & Discussion] cd993:
Xiaomi Mi 9

Battery life saving tips

- Discussion - ​

Presenting a few tips based off personal experience that can help squeeze out those extra few minutes/hours of battery life from our device.​

Please note:

This is not a science and what works for some may not work for others. There are many factors involved in having good battery life and one person’s 1 SOT (screen on time) may mean completely different usage to another’s. For example, 1 hour of internet browsing will of course be less battery-intensive than 1 hour of processor-hungry gaming. So bear this in mind…

I am running the weekly Xiaomi.EU rom (9.4.11 at the time of posting) and so some of these settings/features may not be available on other versions of MIUI.

Some of the below will require. Some users prefer not (or can’t for whichever reason) to root and so you’ll just have to skip those if so.

Lastly, this thread is intended on being a work in progress and I welcome comments/suggestions/additions on the content. These are the settings that I adhere to which I believe, as well as most users, which are useful to aid battery life. Some tips may help out significantly, some may just offer a slight increase. Some may not even help at all and may just be placebo!

If something doesn’t work for you or you greatly disagree, let’s discuss it…​

Network settings + roaming

There are various settings which are known to help out with the notorious Cell Standby drain etc. such as:

Preferred network type (found either by Settings – SIM cards & mobile networks – Sim Card Settings - Preferred network type OR by dialling *#*#4636#*#* via your phone app). Users in the EU find that setting the network type to GSM/WCDMA/LTE or WCDMA/LTE (on both sims) can help stop the device look for network frequencies that it’ll never find, such as the TD-SCDMA etc. You can Google what frequencies your network provider uses which can help you decide.

VoLTE (Settings – SIM cards & mobile networks) – there may be some debate over this one, but it can be said by having VoLTE enabled, whilst calls will be clearer, it will use 4G which is that bit more power hungry. Therefore some testing may be preferred if you’re a frequent caller. I personally have this on without and haven’t tested it fully, but I’m also not a huge caller.

Make calls using WLAN (Settings – SIM cards & mobile networks) – by using WiFi for calls this should be more battery efficient than using mobile network data.

Data roaming (Settings – SIM cards & mobile networks) – I tend to keep Overseas data roaming off when I’m in my home country with the thought that it prevents the device from looking for networks it won’t find. As for National roaming, I have this kept off too normally as I don’t travel around much generally, so again to prevent it searching for alternative networks when it already has a strong signal.

System settings

Here we have several system settings/features that may be used on a day-to-day basis but may not be needed to be enabled at all times. Generally speaking, having something turned on all the time yields benefits for convenience but at the cost of battery life, as seen below.

Wifi / Bluetooth – both of these can be regarded as similar, in the sense that by having it enabled all the time it can connect automatically without your input. For example, if I leave my WiFi on when I leave my home it’ll automatically reconnect when I come back. Great! However, throughout the entire day if it doesn’t find a known network it will constantly be looking for one, draining battery. Not so great. Therefore if the convenience of not having to turn your WiFi on/off is your preference, then leave it enabled. Though if you know you’re not going to be connected to a network, then some manual control may be preferred. The same rules apply for Bluetooth devices.

WiFi & Bluetooth Scanning (Settings – Additional Settings – Privacy – Location – Scanning) – this can be a big drain I have found and is usually activated when you have High Accuracy location mode activated. Again, it comes with its benefits of providing higher accuracy, but with some battery cost. By disabling both WLAN and Bluetooth scanning, extra battery life can be saved. There are some apps I’ve found that force you to enabled High Accuracy mode, so just remember to switch off these scanning settings once again if so.

GPS & location accuracy (Settings – Additional Settings – Privacy – Location – Location mode) – I personally don’t mind just using Device only and keeping this on all the time. As whilst like with Bluetooth as mentioned above, if I know I’m not connect to my Bluetooth speaker for example, I at least like to open Google Maps and it find me straight away rather than toggling GPS on etc. Personal preference of course, as with all of these…

NFC (Settings – More) – as with WiFi and Bluetooth settings, if you’re not using it and don’t mind the manual toggling on/off as needed, then disable and do just that.

Hotspot (Settings – Portable Hotspot) – as above really, as this could be a big drainer if left on. Luckily there is a setting (Turn off hotspot automatically) which can help with this.

Display

A massively subjective aspect of using your device and only you know what you’d rather have and what you;d rather be looking at. Just as we know, a higher brightness level will result in high battery drain and the screen can be the biggest drainer of the all, so choose wisely if you’re trying to conserve some juice.

Screen brightness (Settings – Display – Brightness level) – I personally have it set to manually controlled, as I find the auto-brightness not to be very smooth, at around 20-30% indoors and perhaps up to 100% outdoors. I believe that manually controlling brightness preserves battery as it of course doesn’t use the ambient sensor and brightness remains the same, rather than jumping up and down reacting to light levels.

Ambient display (Settings – Display – Ambient display) – functionality of having the ‘always on display’, but at the cost of some battery life. There is the scheduling that you can use to help with this, but personal preference whether you want this on or not. I personally don’t, though at times I’m tempted to given the notification light, for me, isn’t that practical.

Contrast and colours (Settings – Display –Contrast & colours) – it can be said that Standard will be the most battery friendly, Increased Contrast drawing that bit more power due to the increase in contrast and Automatic Contrast using the most given it will use the sensor to optimise contrast based off available light. I personally have it on Increased contrast and I’m happy enough.

Double tap/raise to wake (Settings – Display – System) – with both of these sensors will be used for the convenience of tapping your screen and raising your phone in order to wake the device. This may be handy, but be mindful that such convenience will come at the cost of the sensors running using up some battery.

Themes

Another subjective aspect of your device is you can make it look. The suggestion here is for black themes to be applied where possible as on our screens black images use less power, as noted by Google. Though indeed black theming isn't for everyone so this suggestion, as with all of them, is purely up to you.

Night mode (Settings - Additional settings - Developer options - Night Mode) - enable night mode (Always on) to turn on MIUI system-wide black/dark theme, such as the dialer etc. *If you don't know how to activate Developer options, see here

Substratum and Swift Black - I highly recommend using this theme with the help of Substratum, though indeed only available to rooted users. Be sure to follow all the required steps to get Substratum working, such as installing the Magisk module etc.

Battery & Performance

Here are the various system battery settings which aim to preserve battery. Some perhaps more useful than others!

Adaptive Battery (Settings – Battery & Performance – Use Adaptive Battery) – this claims to limit battery for apps that you don’t use often, which I have enabled, though as will be seen below some further manual control can be done.

Battery saver / background app restrictions (Settings – Battery & Performance – App Battery Saver – Choose apps) – here you can select per-app a choice of 4 background restriction settings. It’s time consuming, but it’s worth going through each app (note: use the 3 dots in the top right corner to Show system apps) and choose the restriction settings, if any, to be applied. Generally speaking, if you want notifications to come through from it (like WhatsApp) or you don’t want it being shut down in the background (like Spotify) then choose No restrictions. If you’re not so bothered about it and want the system to lay down the law on battery saving, choose Restrict background activity. There are settings in-between, like Battery Saver and Restrict background apps, but I’ll leave you to play around with those ones.

Battery Optimization (Settings – Battery & Performance) - this has several options to save battery ranging from adjusting screen brightness, turning on Battery Saver, turning off GPS etc. This can be used however I prefer to manually configure the settings, so this will be up to you…

Scenes (Settings – Battery & Performance) – here is a ‘smart scene’ called sleep mode which apparently will detect when you’re sleeping and close down apps, restrict NFC etc. I personally have this disabled as again I manually adjust such settings

Auto-start (Settings – Manage apps - *select app* - Autostart) – another useful option is to go through each app you have and disable the autostart, which could provide additional battery savings preventing apps from starting up in the background

Debloating / removing system apps

Lots of system resources can be freed up which can result in added performance and battery life. See the extremely helpful thread by [MENTION=6663802]SirTAVARES[/MENTION] who created the Debloat Applications (No-Root) thread.

I personally have used the above guide to remove a lot of pre-included apps, even on the somewhat pre-debloated Xiaomi.eu rom. Without root you can use ADB to remove apps and they won't reappear when you update your rom. They will appear back if you perform a factory reset, as they are not fully uninstalled.

Furthermore, with root you can remove the app from not only the user area but system area too. Check out the thread for more info on this.

Lastly, apps like System App Remover Pro can fully uninstall system apps, with the option to use the Recycle Bin option should you wish to restore

Battery draining apps and alternatives

It can be said that some apps are notorious for being big battery drainers, such as the official Facebook app. I’m not a huge user of some of the other apps, like Snapchat, Twitter etc. and to be honest I generally favour webpage versions of some things for example I don’t have the Amazon shopping app, I just use the web page version, saved as a bookmark on my home screen. The general tip here is if you are going to use an app, be sure to go through its settings and adjust notification settings/frequency. For example, I do have the Sky News app however set it to not notify me of news, the same for Yahoo weather. So tweak accordingly. If you have some good alternative app suggestions then I’ll be happy to include some here, but for now I’ll just start with…

Facebook – I use Folio for Facebook & Messenger which is a nice lightweight 'Facebook wrapper' in that it uses the Facebook webpage as the basis for the app. It also has a functional messenger included so no need for a separate app.

Battery monitoring apps - apps like GSam Battery Monitor and BetterBatteryStats can be useful in detecting the high draining apps, so could be worth using one of those in an effort to identify them.

Magisk modules

There are many Magisk modules out there which aim to solve battery. I only use one, which I’ll list below, however please feel free to make suggestions for inclusion in this section. I know that there are some like Greenify, Amplify (when using Xposed) etc. that could squeeze even more juice out of the device!

Universal GMS Doze - helps put Google Play Services to sleep to save some battery. I use this with no issues/impact on Gmail, Play Store etc.

Other system settings

Sync (Settings – Sync) – as with per app settings for notifications/sync frequency etc. settings, it’s worth checking here to see what apps are auto-syncing data. You can turn them all off (I believe) via the Auto-sync data toggle, or check them out individually via this menu setting. *Note: I have removed Mi Cloud etc. and so I don’t have any of that running in the background, but that’s up to you.

Vibration (Settings – Sound & Vibration) – now this is likely a very small potential for some battery savings but still worth noting. You can adjust the Vibrate on tap option ranging from Off/Light/Medium/Strong, which I’m sure someone who has it set to Strong will be using that tiny bit more power than someone who has it set to Off. Your call….

Permissions (Settings - Permissions - Permissions) - it's worth going through here to monitor per-app what permissions are being used. Some apps may not like being prevented using certain things and it may break some functionality, but it's an extra method in reducing potential usage, such as hardware usage, for an extra saving. For example, an app may try and use GPS each and every time you open it or even try running it in the background. If you're willing to, preventing it from doing so may help save some battery.

Authorization & revocation (Settings - Additional settings - Authorization & revocation) - here you can revoke some access from apps. I have stuff like Security, Downloads, Battery and performance and Settings listed here, all of which I've revoked with no noticeable negative consequences.

Fingerprint icon (Settings - Lock screen & password - Manage fingerprints) - another very small tweak for a potential very small saving. The setting is Show fingerprint icon when the screen is off (which is present on Xiaomi.eu 9.4.11) and by disabling will prevent the icon showing. As the icon is displayed by the screen, by turning it off it'll naturally save the power it takes to light the screen up, which as you may have noticed, it lights up with the tiniest movement of the device! I keep it on as I like it and battery doesn't seem to be greatly impacted - but this thread is about squeezing as much juice as possible, right?!

Recents and 'Clear all' - not a system setting but a little thing to do, is to open up the Recents menu and use the 'X' button to close all running apps, or swipe individual to close certain ones from running in the background. Now, it is the case the apps stored in the RAM aren't necessarily using battery, but this is still useful to stop apps that are running and active. Definitely a debatable one, as the argument against doing this is that it then uses battery to reopen the app, so perhaps just test it out and see for yourself.

Last but not least....

Now this last little tip of mine is certainly one that can be debated, but I do it nonetheless...

Remember, none of this is advice as such, it's just what I do to keep myself sane in knowing/believing (philosophical debate here?!) that I've done all I can to maximise battery life.

What I like to do is when installing a rom have the phone charged to 100% before doing so. This originates from the days of believing that batteries need to be calibrated. There is definitely lots of research that states it may not be needed and a simple Google search can reveal research into this, but it's something I like to do anyway.

So essentially my method regarding this, needed or not, is:

Charge phone to 100%

Update rom

Use phone until it switches off at 0%

Charge phone fully to 100% without interruption

I'm not stating this is needed, it's just what I do. Take it or leave it! I'm aware that there is science behind not allowing phone batteries to die at 0% in order to prolong the life of it, but again, it's just what I do and it works for me.

Your call!

That is it for now. As mentioned I highly welcome your comments and suggestions for adding to this thread so please do let me know if any questions etc.I'm purposefully not showing my SOT/battery stats as they won't be useful to anyone - the above tips are here for that!​