Xiaomi Redmi Note 8 Pro
battery-blown
In this article, we’ll look at all the possible reasons why the Redmi Note 8 Pro has been charging for a long time, from the banal wear of the cable to the hidden settings of MIUI that limit current. You’ll learn how to diagnose the problem yourself, what tests to run and when to carry the phone into the service. For convenience, we’ve collected unique data on typical malfunctions of this model — for example, why the original 18W power supply sometimes produces only 5 watts, and how to fix it without replacing parts.
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1. Power supply and cable check: why 18W turn into 5W
The first thing to rule out is a charger or cable malfunction. Redmi Note 8 Pro supports quick charging Quick Charge 3.0 (18 watts), but if the power supply or cable is damaged, the phone automatically switches to standard mode (5 watts), which increases the charging time from 1.5-2 hours to 4-5.
How to check:
- 🔌 Connect your phone to another power supply (preferably the original one from Xiaomi). If the charging speed has increased, charging is a problem.
- 📱 Try another cable, even if it looks good on the outside, and microcracks in the squirt or oxidized contacts reduce current.
- 🔍 Check the connector. USB-C on the phone: if dirt accumulates inside or contacts are bent, charging will be interrupted.
Feature Redmi Note 8 Pro: it does not support charging from USB-You'll get the maximum from a computer port or power bank at full power, 7.5 to 10 watts. A full fast charge requires a Quick Charge 3.0 or Power Delivery power supply.
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If you don't have the original power supply, use Samsung (Adaptive Fast Charging Series) or OnePlus (Dash Charge) charging. These are compatible with the Redmi Note 8 Pro and deliver a full 18 watts.
Battery wear: when capacity falls below 70%
The average battery life of the Redmi Note 8 Pro is 2-3 years when used actively. After 500-600 charging cycles, the battery capacity decreases by 20-30%, and the power controller begins to artificially limit the current to extend the battery life, as a result, the phone charges 1.5-2 times slower.
How to check the wear:
- Install the AccuBattery app (available on Google Play).
- Charge your phone to 100% and check the battery health setting.
- If the value is below 80%, the battery is critically worn out and needs to be replaced.
Signs of a worn-out battery:
- ⚡ The phone is discharged in 3-4 hours with moderate use.
- 🔥 The body warms up even with a simple charge.
- 📉 The percentage of charge "jumps" (for example, from 30% immediately to 10%).
⚠️ Warning: If the battery is swollen (the phone body has become convex or the screen "steps away" from the frame), immediately disconnect it from charging and contact the service!
3.Overheating: Why the phone 'strangles' charging at 40°C
Redmi Note 8 Pro is equipped with a system of protection against overheating, which automatically reduces the charging current if the battery temperature exceeds 40-45 ° C. This can occur even in normal conditions:
- 🌞 Charging in the sun or in a hot room.
- 🎮 Games or video while charging (Mediatek Helio processor) G90T hot).
- 🔋 Use of a non-original power supply unit with poor current stabilization.
How to check the temperature:
- Install the AIDA64 application.
- Go to the Sensors section and look at the battery temperature.
- If the value is above 38°C, let the phone cool down before charging.
Cooling tips:
- 🧊 Remove the case while charging.
- 📵 Do not use your phone for games or videos while charging.
- 🌬️ Charge in a ventilated room (not in a car in the sun!).
What happens if you ignore the overheating?
4. Software glitches: why MIUI limits charging
Sometimes slow charging is not about hardware, but about software settings. MIUI has several features that can artificially limit current:
| Function | Wherever | How does charging affect |
|---|---|---|
| Optimized charging | Settings → Battery → Battery settings | Limits the charge to 80-90% to extend the battery life. |
| Energy saving regime | Settings → Battery → Energy saving mode | Reduces the charging current and disables background processes. |
| Background activity of applications | Settings → Applications → Permissions → Autorun | Some applications (such as instant messengers) consume energy during charging, slowing down the process. |
How to disable restrictions:
- Go to Settings → Battery → Battery settings and turn off “Optimized Charging”.
- In the Power Saving Mode section, select High Performance Mode (if available).
- Close all background apps before charging (especially games and social media).
Turn off optimized charging|Check the energy saving mode|Close background annexes|Update MIUI last-minute-->
5 Power controller damage: When the phone 'doesn't see' charging
If all external causes are ruled out, but the Redmi Note 8 Pro still charges slowly (or does not charge at all), the problem may lie in the power controller - the chip that regulates the current supply to the battery.
- 🔌 Phone is connected to charging, but the indicator does not burn or flashes.
- ⚡ The charge is jerky (fast, then slow).
- 📉 The percentage of charge “hangs” on one value (for example, 80%).
Causes of Controller Failure:
- ⚡ Voltage surges in the network (for example, when using poor-quality extension cords).
- 💧 Moisture entering the connector USB-C.
- 🔧 Failed firmware or reset settings.
⚠️ Attention: Self-repair of the power controller is almost impossible - it requires soldering of the chip on the board. If you suspect this malfunction, contact the service center. The average cost of repair is 2 000-4 000 rubles (depending on the region).
6 Unoriginal accessories: why cheap cable kills the battery
Many users save on accessories by buying cheap cables and power supplies on AliExpress or in transition stores, but the Redmi Note 8 Pro is sensitive to the quality of chargers:
- 🔌 Uncertified power supplies can produce unstable voltage, leading to overheating of the battery and accelerated wear and tear.
- 📱 Cables without Quick Charge support limit current to 5-10 W, even if the power supply is powerful.
- ⚡ Fakes for original Xiaomi accessories often do not have protection against short circuit.
How to choose a safe accessory:
- 🛡️ Buy Power Packs with Quick Charge 3.0 Certification or Power Delivery.
- 🔍 Check the labeling on the cable: the original Xiaomi cables have the inscription 5A (jack.
- 📦 Avoid "sets" (block) + cable) for 200-300 rubles - they are almost always low-quality.
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Using non-original accessories not only slows down charging, but also reduces battery life by 30-40%.
7.Firmware Recovery: Why the MIUI Update Resets Charging Settings
After the MIUI update, some users notice that the Redmi Note 8 Pro has become slower to charge.
- 🔄 Reset battery settings (optimized charging by default is enabled).
- 🐞 Bug in the new firmware version (for example, in the MIUI 12.5 There were problems with the power controller).
- 📱 User Settings Conflict (if you have previously changed battery settings through a ADB).
How to fix it:
- Go to Settings → Battery → Battery settings and turn off all optimizations.
- Make a cache reset via recovery: 1. Turn off the phone. 2. Press Power + Volume Up. 3. Select Wipe Cache Partition.
- If the problem persists, roll back to the previous version of MIUI via Fastboot.
⚠️ If after firmware the phone stopped charging at all, do not try to “resuscitate” it through EDL-You can call the service, and the wrong actions can finally kill the motherboard.
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