Why Xiaomi Redmi 8 is fast discharge and how to fix it: a step-by-step guide

Your Xiaomi Redmi 8 held a charge for a day, and now barely lasts until the evening? the battery sits down 20% per hour in standby mode, and after 30 minutes of games the phone already requires recharging? The problem is not in your imagination - over time even high-quality batteries degrade, but in 80% of cases, software failures or improper settings are to blame, not an "obsolete battery."

In this article, 12 working methods for restoring autonomy, from basic (cleaning the cache) to radical (replacing the battery). MIUI For Redmi 8, which eats charge in the background, and show you how to get around them without losing functionality (SN: HB41 and HB61) and relevant to versions MIUI 12–14.

Spoiler: If the phone only runs out when it's in active use (games, video, navigator), the problem is more hardware, wear on the battery or the power controller. If the charge goes away even at night in sleep mode, the software is to blame. Let's start with the diagnosis.

1. Diagnosis: how to understand what exactly eats the charge

Before you treat it, you have to make a diagnosis. Redmi 8 has built-in power monitoring tools, but they're hidden in the back of the settings. Here's how to use them:

Open the Settings. → Battery and productivity → Battery usage. Here you'll see a discharge graph and a list of applications that are sorted by energy consumption:

• 📊 Uneven schedule – if the charge falls in “steps” (for example, from 80% to 60% in 10 minutes), this is a sign of a faulty charge controller.
• 🔋 High standby consumption (more than 5% per hour) – background processes or screen wake-ups are to blame.
• 🎮 Games/social networks are normal when used actively, but if they are there even after closing, they should be limited.
• 📡 Mobile network or Wi-Fi in leaders – signal problem (phone constantly looking for network).

For detailed diagnosis, use the hidden menu of engineering settings. Enter the phone app code:

##4636##

Go to the Battery Information tab. The charge level should match the status bar. If the difference is greater than 10%, calibration of the battery is required (see section 3).

2.Program reasons: 5 settings that kill the battery

MIUI It's known for its "aggressive" background consumption, which is that it's constantly syncing data, updating widgets, and storing unnecessary processes in memory:

Autosynchronization and geolocation

By default, Redmi 8 syncs contacts, email and calendars every 15 minutes, while Google and Xiaomi track location for targeted ads.

• 📍 Settings → Confidentiality → Permits → Geolocation → Disable for unnecessary apps (such as Mi Video or Cleaner).
• 🔄 Settings → Accounts and synchronization → Turn off autosynchronization for non-critical accounts (e.g. Mi Account if you are not using the Xiaomi cloud).

Optimization MIUI (lip-service)

V MIUI 12+ There's an undocumented Ultra Battery Mode feature that limits background activity:

1. Go to Settings → Battery and Performance → Battery Modes.
2. Select Ultra Mode (if not, upgrade to the latest version).
3. Enable the option to limit background activity for all applications except instant messengers.

💡

After the update MIUI phone began to discharge faster, reset the battery settings: → Battery → ⚙️ → Reset the battery statistics. This will remove the accumulated errors in the consumption data.

Widgets and live wallpaper

Dynamic wallpaper and weather/news widgets are updated every 30-60 minutes, even when the screen is off.

• 🖼️ Install the usual wallpaper: long press on the desktop → Wallpaper. → pick from the gallery.
• 📱 Remove widgets: long press on the widget → Delete.

Auto-update of applications

Google Play and Mi App Store update apps by default over Wi-Fi and mobile, even in roaming.

• 📱 Play Market → Settings → Auto-update of applications → Choose Not to Update Automatically.
• 🔄 Mi App Store → Profile → Settings → Auto-update → turn off.

Screen "awakenings"

Each screen switch (even for 1 second) eats away. ~0.5% charge. Check what's waking your phone:

• 🔔 Settings → Notifications → Notification panel → Turn off unnecessary notifications (e.g. from games).
• 📱 Settings → Display. → Screen locking → Turn off the Wake Up and Double Touch to Wake Up.

💡

Even in sleep mode, the Redmi 8 consumes up to 2% of its charge per hour due to background processes, a normal rate of no more than 0.5-1% per hour.

3.Battery calibration: when the phone shows the wrong percentage

If your Redmi 8 suddenly turns off at 20 to 30 percent charge or after charging shows 100%, and after 5 minutes falls to 80%, the problem is in the desynchronization of the battery controller. This is treated by calibration, but you need to do it correctly, otherwise you can aggravate the wear of the battery.

⚠️ Attention: Calibration erases data on charge cycles and can temporarily impair autonomy. Do it no more than 1 time in 3 months.

Step-by-step:

1. Charge your phone to 100% original charger (18W). Do not use wireless charging or powerbank.
2. Disconnect from the network and let work 2-3 hours (you can watch a video or play).
3. Turn off your phone and plug in the charger for another 1 hour (even if the light is green).
4. Turn off the charging, turn on the phone and wait for full discharge until the automatic shutdown.
5. Charge up to 100% without interruptions (do not turn on your phone while charging).

After calibration, check the actual battery capacity in the engineering menu (#4636##). Battery Health should be above 80%. If lower, the battery is worn out and needs to be replaced.

4. Hardware problems: when it is not the fault of software

If all the software methods have been tried and the Redmi 8 still runs out in a few hours, the problem is the hardware.

⚠️ Warning: If the phone is swollen (screen or back cover is raised), immediately turn it off and don't try to charge.

How to check the wear of the battery

You can find out the real status of the battery using the AccuBattery app (free of charge in the Play Market), after 2-3 charging cycles, it will show:

• 📉 Real capacity (for example, 3800 mAh instead of the declared 5000 mAh).
• 🔄 Number of charging cycles (more than 500 cycles – critical wear).
• ⚡ Discharge speed in mA/h (normal standby mode - up to 50 mA/h).

If the capacity has dropped below 60% of the original capacity (less than 3000 mAh for the Redmi 8), it is time to change the battery. HB41 (5000 mAh or HB61 (The cost of replacement in the service center - from 1500 to 2500 rubles.

5. Charging optimization: how to extend the life of the battery

Even a new battery won't last long if you don't charge your phone correctly. Redmi 8 has a lithium polymer battery that degrades when you:

• ⚡ Overheating (over 40)°C).
• 🔌 Constant connection to charging (for example, at night).
• 📉 Deep discharge (below 5%).

Charging rules for Redmi 8:

• 🔋 Use the original adapter 18W (model MDY-08-EQ or MDY-08-EU). Fast charging doesn’t hurt the battery if the phone doesn’t heat up.
• 🌡️ Do not charge at a temperature below 10°C or higher than 35°C (optimum 15-25)°C).
• 🕒 Turn off charging by 80–90% (in Settings) → Battery → Battery modes are optional to limit the charge to 80%).
• ⚡ Avoid wireless charging – it heats the battery stronger than wired charging.

⚠️ Warning: If the phone doesn't charge above 80-90% on its own (without setting limits), it's a sign of a controller malfunction or battery wear.

6 Radical methods: reset, firmware, replacement

If nothing works, extreme measures remain: they take time and sometimes technical skills, but often return the Redmi 8 to factory autonomy.

Reset to factory settings

The reset removes all the data, but it cleans the system of the accumulated debris.

1. Backup: Settings → Additional → Backup and Reset → Local Backup.
2. Remember the data of the Mi Account (after reset, you will need to enter a login / password).
3. Go to Settings → About Phone → Reset settings and select Erase all data.

After reset, don't restore the data from the backup, it will return the old settings that may have caused the discharge. Install the applications again.

6.2 Flashing through Fastboot

If the problem occurs after the update MIUI, Go back to the stable firmware version:

1. Download the official firmware for Redmi 8 (codenamed Olivelite) from Xiaomi Firmware.
2. Unpack the archive and place the file flash_all.bat firmware.
3. Connect your phone to your PC in Fastboot mode (clip Volume Down + Power when your phone is off).
4. Launch it. flash_all.bat on behalf of the administrator.

⚠️ Warning: Continuous interruption of firmware can stain the phone (make it inoperable). Use only original cables and ports. USB 2.0.

Replacement of the battery

If the battery is worn out (capacity) < 60%), it's the only solution:

• 🛠️ Make it yourself (you need a set for opening, a soldering iron to disconnect the plume and a new battery).
• 🔧 Contact the service (work guarantee – 3-6 months).

The cost of the original battery — ~1200-1500 rubles, work on replacement — ~800-1000 rubles. after replacement, be sure to perform calibration (section 3).

7.Alternative Solutions: How to Prolong Self-Autonomy in the Here and Now

While you’re solving the battery problem, here are a few ways to “squeeze” the most out of your current charge:

• ⚡ Turn on the plane at night or when the network signal is weak (1-2 divisions), this will reduce consumption by 3-5 times.
• 📴 Turn it off. 4G/LTE, If you do not need the Internet: Settings → SIM-maps and mobile networks → Preferred type of network → 3G.
• 🔇 Reduce the brightness of the screen to 30-40% and turn on Adaptive Brightness.
• 🕒 Set a dark topic (AMOLED-Redmi 8 doesn’t have screens, but darker colors save up to 10% of the charge).
• 🎧 Use wired headphones instead of Bluetooth (savings) ~5–7% per hour of listening to music).

If your phone is dead and you don’t charge, try emergency mode:

1. Connect any charger (even from another phone).
2. Press Volume Up + Power for 10-15 seconds.
3. The phone will be turned on in the mode of minimum consumption (without background processes).

FAQ: Frequent questions about the Redmi battery 8