Why the battery is quickly discharged on Xiaomi Redmi Note 8 Pro: full analysis

Xiaomi Redmi Note 8 Pro with its powerful MediaTek Helio processor G90T And a capacious 4,500 mAh battery should hold a charge for at least a day with moderate use, but many owners face the problem: the smartphone sits down in 4-6 hours, or even faster?

The causes can be both software failures and battery wear. In this article, we will examine all possible factors, from background processes to factory defects, and give step-by-step instructions on how to diagnose and fix the problem» MIUI, which often go unnoticed.

Spoiler: 70% of the time, it’s not the fault, but the user’s settings and habits, but there are exceptions, such as a defect in the power controller in the 2019-2020 batches, which Xiaomi has not officially reported.

1. Checking the status of the battery: how to find out the real wear

Before you sin on software, check the physical condition of the battery. Even with careful use in 2-3 years, the capacity drops by 20-30%. In the Redmi Note 8 Pro, critical wear begins after 500-600 charging cycles.

How to check:

• 🔋 Enter the phone code ##4636 in the app## → Select "Battery Information." Compare the current capacity with the passport (4500 mAh).
• 📊 Install the AccuBattery app (the free version will show wear in percentages).
• 🔧 B Settings → The phone. → Battery status (available on MIUI 12+).

Normal readings:

⚠️ Warning: If the capacity has fallen below 3,000 mAh and the phone is shut down at 20 to 30% charge, this is a sign of swelling of the battery!

2. voracious applications: Who steals your charge?

The main reason for rapid discharge is the background activity of applications, and even closed programs can use up to 30% of the charge per day through:

• 📱 Push notifications (especially messengers and social networks).
• 📍 Geolocation (maps, taxis, fitness trackers).
• 🔄 Auto Update (Play Market, Social Networks, Mail).
• 🎮 Background games (e.g, PUBG Mobile or Genshin Impact is not closed).

How to find and disable energy vampires:

1. Go to Settings → Battery and Performance → Battery Use.
2. Sort the list by expense for the last 24 hours.
3. Click on the app. → Select “Limit background activity».
4. For extreme cases: Settings → Annexes → Application management → [name] → Battery → Prohibit auto-start.

Disable Auto Update in Play Market|

Ban background activity for social networks |

Turn off geolocation for unnecessary applications|

Limit Notifications from Games and News Services-->

Pay special attention to system processes:

• 🤖 Android System (normal: 5-10% per day; if more – a malfunction in the firmware).
• 📡 Mediaserver (guilty of expense if you listen to music or watch videos).
• 🔄 Google Play Services (optimized through Settings) → Google → Google account → Synchronization).

3. MIUI settings that kill the battery

MIUI It's known for its "improvement" that often works against the user. Here are the hidden features that make the Redmi Note 8 Pro discharge faster:

1. Automatic optimization RAM

System Acceleration in Settings → Special opportunities → The memory is constantly clearing the background processes, causing them to restart, which increases the load on the processor and, as a result, battery consumption.

2. "Smart Assistant" (Second Space)

If you are using a second desktop (Settings) → Second Space, which duplicates background processes for both spaces, can add up to 15 percent of the daily consumption.

3. Automatic brightness with "backlight"

V MIUI It's a function of Auto Brightness. + (Settings → Display. → Brightness → Automatic brightness → Additionally), which artificially inflates the brightness in dark rooms!

4. "Fast Charging" in Standby Mode

Even when the phone is not working, MIUI It can include accelerated charging to maintain the battery level, which leads to overheating and accelerated wear. → Battery → Quick charging (uncheck the tick from "Enable in standby mode»).

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After disabling “smart” functions MIUI Reboot your phone – it will reset the background processes and show the real effect of the changes.

4. Problems with firmware and updates

Failures after updates are a classic Xiaomi problem, especially when it comes to transitions between versions. MIUI (For example, from 12 to 13) or regional firmware (Global vs China).

Signs of "broken" firmware:

• 🔄 The phone is discharged by 1-2% per minute in idleness.
• 🌡️ Overheating without load (especially in the upper part of the body).
• 🔋 B Settings → Battery consumption on Android System or Kernel over 20%.

How to fix it:

1. Reset the cache: 1. Turn off the phone. 2. Squeeze the power. + Volume up until the Mi. 3 logo appears. From the Recovery menu, select Wipe Cache → Reboot.
2. Download the official firmware for the Redmi Note 8 Pro (codename begonia) from en.miui.com. Use the Mi Flash Tool to flash it back (spoiler instructions).

⚠️ Attention: Fastboot firmware erases all data! pre-backup through Settings → Additionally. → Backup.

5. Hardware problems: when iron is to blame

If the software methods didn't work, the problem could be physical malfunctions.

Defect of the power controller

In the batches of Redmi Note 8 Pro 2019-2020, there was a marriage of the chip PMIC (Power Management IC). Symptoms:

• The phone does not hold a charge above 80-90%.
• When connecting the charging, it shows Not Charging or Charging is suspended.
• Accidental reboots at a battery level of 30-50%.

Solution: only replacement of the board or chips in the service center.

2. Oxidation of battery contacts

If the phone falls or comes into contact with moisture, oxides can appear on the battery connector, which leads to unstable power supply and rapid discharge.

• Remove the back cover (requires a mediator and a hair dryer to soften the glue).
• Check the battery contacts for green plaque or corrosion.
• Clean with alcohol and cotton (do not use metal objects!).

3. Non-original battery

If the battery has already changed, there's a high risk that you've got a cheap one.

• Capacity in #4636## shows 2000-3,000 mAh instead of 4500.
• The phone heats up when charging more than usual.
• The charge drops in leaps (for example, from 50% to 20% in 10 minutes).

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If after replacing the battery, the phone began to discharge faster - return to the service and demand the original part (article). MB-J40> For the Redmi Note 8 Pro).

External factors: charging, temperature, network signal

Even a serviceable Redmi Note 8 Pro will land quickly if:

1. A substandard charger is used

Cheap cables and power supplies can:

• 🔌 Undercharge the battery (the phone shows 100%, but really 80-90%).
• 🌡️ Overheat the power controller, accelerating wear.
• 🔋 Issuing unstable voltage, which leads to false charging cycles.

Solution: Use the original Xiaomi block (18W) Certified analogues (Anker, Baseus).

Extreme temperatures

Redmi Note 8 Pro battery works optimally at 10-35°C. In violation of this range:

• ❄️ In the cold (<0°C) the container temporarily falls on 30–50%.
• 🔥 Overheating (>40°C) the battery is degraded 2-3 times faster.

3.Weak signal of the network

If you're in a low-cost area (such as in the subway or out of town), your phone uses up to 40 percent of the extra energy to find the network.

• 📶 B Settings → SIM-Maps and mobile networks only enable 4G (if 5G needless).
• 🔄 Turn off automatic network search (Settings) → Mobile network → Choice of network → Manually).

7. Battery calibration: myth or reality?

Many people advise to "calibrate" the battery, but few explain how it actually works.

1. After the battery was replaced.
2. If the phone suddenly turns off at 20-30% charge (controller failure).

How to calibrate correctly:

1. Discharge the phone before automatically shutting down.
2. Do not turn it on and connect it to the original ROM.
3. Charge at least 8 hours (yes, even if the indicator shows 100% sooner).
4. Turn off the charging, turn on the phone and wait for the full load.
5. Repeat the discharge/charging cycle again.

⚠️ Attention: Calibration won't restore the capacity of the worn-out battery! It only synchronizes the controller data with the actual state of the battery.

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If the problem persists after calibration, it is a sign of physical battery wear and tear, not software failure.

8.Alternative solutions: from root to battery replacement

If nothing has worked, radical measures remain:

1. Root access and core

With Magisk and custom core (e.g. FrancoKernel) you can:

• 🔧 Disable unnecessary system processes.
• 📉 Reduce the processor frequency to simple.
• 🔋 Optimize battery consumption at core level.

Cons: loss of warranty and the risk of “bricking” the phone.

2. Battery replacement

The cost of the original battery for the Redmi Note 8 Pro is about 1500-2000 ₽. Signs that it's time to change:

• Bloating (check if the phone is on the table).
• Capacity on AccuBattery is below 3000 mAh.
• The phone turns off at 30-40% charge.

3. Transition to custom firmware

Firmware like LineageOS or Pixel Experience are devoid of “chips» MIUI, They're all battery-devouring:

• ⚡ Pure Android without background processes.
• 🔄 Regular security updates.
• 📉 15-20% lower battery consumption.

Cons: There are no Xiaomi branded features (like Second Space or Game Turbo).

FAQ: Frequent questions about the Redmi Note battery 8 Pro