Why Xiaomi Redmi Note 8T is fast discharge and how to fix it: the full guide 2026

Xiaomi Redmi Note 8T, The 2019 smartphone is still a popular smartphone due to its balanced specs and affordable price, but many owners face the problem that the battery will run out in a few hours, even if the phone is idle. Is the battery, firmware or your usage habits to blame?

In this article, we'll look at all the possible causes of rapid discharge, from the banal wear of the battery to the hidden energy-consuming processes in the system. You'll get step-by-step instructions with photos, tests for diagnostics and ways to restore autonomy without going to the service. And if the problem is hardware, you'll learn how to choose a quality battery to replace and not run into a fake.

Important: The methods are suitable for other models of the Redmi Note 8-The series (Note) 8/8 Pro, because they're built on the same platform, but some of the settings may be different -- we'll point this out separately.

1.Diagnostics: How to understand why Redmi Note 8T discharge

Before you fix something, you need to identify the source of the problem, and 80 percent of the time, it's not the fault, it's the software settings or the user's habits.

Open the Settings. → Battery and pay attention to:

• 📊 Schedule of discharge: flat line - the norm, sharp jumps - a sign of a "gluttonous" process.
• ⚡ Top power consumption: if the screen or Android system is the first, it is expected, and if the little-known application (for example, com.android.XXXX) leads, it should be removed.
• 🔋 Battery condition: If the capacity is below 80% of the original (3500 mAh), the battery is worn out.

For deep diagnosis, use the hidden menu of engineering codes:

1. Open the Phone app.
2. Enter the combination: ##4636###.
3. Select Battery Information and check: Charge level (should match the status bar indicator) Status (if Good, battery is fine) Temperature (normal: 25-40)°C; above 45°C - overheating!).

If the battery temperature in the engineering menu exceeds 45°C in normal use, it's a critical signal. Most likely, the battery is worn out or the charging board is damaged - in this case, self-repair is dangerous (risk of fire.

Programmatic reasons: what "eats" the charge in the background

Most often, the battery dies due to hidden processes that the user does not even notice.

Pay special attention to auto-run apps, and many instant messengers (like Telegram or WhatsApp) are set to work in the background by default, to fix this:

1. Go to Settings → Applications → Permissions → Autorun.
2. Turn off auto-start for all applications except critical ones (calls, SMS).
3. For MIUI 12+: Check the settings further. → Battery → Power saving mode and turn it on for unnecessary applications.

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If after disabling autorun no notifications from messengers, add them to the exceptions in the Settings section → Notifications → Priority notifications.

3. Hardware problems: when the battery or iron is to blame

If software methods don't work, the problem may be the physical wear and tear of the components, and here are the signs that it's time to change the battery or check the hardware:

• 🔌 The phone is discharged by 20-30% per hour in standby mode.
• 🌡️ The body warms up even with minimal load.
• ⚡ Charging is jerky or interrupted (for example, shows 80% and does not go on).
• 📉 B Settings → Battery capacity below 2500 mAh (at the initial 3500 mAh).

To check the battery status accurately, use the AccuBattery app (available on the Play Store). Run 2-3 charge/discharge cycles and see:

• Real capacity (if less than 60% of the original - the battery for replacement).
• The rate of wear (normal: up to 1% per month; if more - the battery degrades rapidly).
• Temperature (above 40)°C when charging - a sign of malfunction).

If the diagnostics show that the battery wears out, it needs to be replaced. 8T fitting battery with labeling BM47 (original BTB419 (Cost: 800-1500 rubles. Attention: buy only from trusted sellers - counterfeits can swell or ignite!

Buy the original battery (marking) BM47/BTB419)

Prepare tools: plastic mediator, screwdriver T4

Make a backup copy of the data (in case of reset)

Charge your phone to at least 30% (for safety)

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4. MIUI Optimization: Hidden Settings to Save Charge

MIUI — Xiaomi's branded shell, known for its voracious background consumption, but it has hidden features that will help extend the operating time:

1. Extremely low power consumption mode

This mode disables all background activity except calls and SMS. It's like this:

1. Settings → Battery → Energy saving regime.
2. Choose ultra-low power consumption.
3. Click Enable and confirm.

In this mode, the phone will last 30-50% longer, but some functions (for example, notifications from social networks) will be disabled.

2. Disable animation and visual effects

The animations and the smooth transitions look beautiful, but they waste a lot of power to turn them off.

1. Turn on Developer Mode (7 times click on the MIUI version in Settings → About Phone).
2. Go to Settings → Additional → For developers.
3. Find the items: The scale of window animation → No animation. Scale of transition animation. → No animation, duration of animation. → Shut down.

3. Optimization of the processor

Default Redmi Note 8T It uses all 8 cores of the Snapdragon 665 processor, even when they are not needed:

1. Install Kernel Adiutor (root rights required)
2. In the section CPU elect the Governor → Powersave.
3. Limit the maximum frequency to 1.6 GHz (instead of the standard 2.0 GHz).

⚠️ Warning: changing the kernel settings can cause the phone to run in an unstable way. If you have lags after optimization, return the settings to factory settings.

Charging according to the rules: how to extend the life of the battery

Many users incorrectly charge the Redmi Note 8T, This is what speeds up battery wear. Here are 5 rules to help you keep your capacity:

1. Don't discharge to 0%. Optimal range is 20-80%. Complete discharge reduces battery life by 10-15% per cycle.
2. Charges from other devices (especially fast on 18)+ W) may overheat the battery.
3. Do not charge in the heat or cold.Perfect temperature: 10–30°C. In the cold (-10°C. the battery loses up to 30% temporary.
4. Turn off fast charging. in the Redmi Note 8T It's implemented via Quick Charge 3.0, which heats the battery. To disable: Go to Settings → Battery → Quick charging. Uncheck the tick from Fast Charging.

Keep your phone with 50% charge

To check the quality of the charger, use the Ampere app (showing charging current). Normal values for the Redmi Note 8T:

• Original Zoo (5V/2And): 1000–1500 ma.
• Fast charging (9V/2And): 1500–1800 ma.
• If the current is below 500 mA, the cable or power supply is faulty.

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Using non-original chargers with power above 18W (e.g., from the Redmi Note 10 Pro) can cause the power controller to overheat in the Redmi Note. 8T and his outage.

6. Radical-methods: reset, firmware and custom solutions

If nothing works, then radical measures remain, they take longer, but often solve the problem once and for all.

1.Reset to factory settings

It'll delete all the data, but it'll clean up the system.

1. Create a backup (via Settings → Additional → Backup).
2. Go to Settings → About the phone → Reset settings.
3. Choose to erase all data and confirm.

After reset, do not restore data from the backup immediately – check how the battery behaves on a clean system.

2. Updating or flashing MIUI

Sometimes, firmware bugs cause a high discharge.

1. Go to Settings → About the phone → System update.
2. If the update is available, download and install.
3. If there are no updates, but the problem remains – try the manual firmware through the Mi Flash Tool (instructions on the official Xiaomi website).

⚠️ Warning: Firmware via the Mi Flash Tool erases all data and can result in a phone lock if the wrong version is selected MIUI. Use only stable firmware for Redmi Note 8T (codename: willow).

3. Installation of a custom core or firmware

For advanced users: custom firmware (like LineageOS or Pixel Experience) is often optimized better than standard firmware. MIUI. But they will need to be installed:

• Unlock the loader (official instructions).
• Install custom recovery (TWRP).
• Sweep through the new firmware and core.

Advantages:

• ✅ No extra services. MIUI.
• ✅ More flexible energy consumption setting.
• ✅ Regular security updates.

Disadvantages:

• ❌ Loss of warranty (if it is still valid).
• ❌ The risk of “bricking” the phone in case of an error.
• ❌ Certain functions (e.g, IR-blaster) may not work.

7. Alternative solutions: if nothing helps

If all methods are tried, but Redmi Note 8T It still discharges in a few hours, consider these options:

1. Power Bank as a permanent solution

Carrying an external battery of 10,000 to 20,000 mAh is not ideal, but practical.

• 🔋 Xiaomi Mi Power Bank 3 Pro (20000 mAh, fast charging).
• 🔋 Baseus 65W 20000mAh (supportive PD and QC 3.0).
• 🔋 Anker PowerCore 26800 for long journeys).

2. Replacement of telephone

If Redmi Note 8T It's been in service for more than 3-4 years, and it might be time to consider replacing it. POCO X5) have more capacious batteries (5000 mAh) and energy efficient processors.

3. Use of the telephone in "light" mode

If you don’t want to buy a new smartphone, set up a Redmi Note. 8T as a "call" with minimal functionality:

• 📵 Turn off mobile data and Wi-Fi, leave only calls/SMS.
• 🖼️ Install the black wallpaper (for the purpose of the AMOLED-screen-savings).
• 🚫 Remove all applications except those required.
• ⏳ Turn on Night Flight Mode.

In this mode, the phone can work 2-3 days without recharging.

FAQ: Answers to Frequent Questions