Xiaomi Redmi 9T is charging too long: all the reasons and how to speed up the process

Xiaomi Redmi 9T is one of the most popular budget smartphones with a capacious battery of 6000 mAh, but many users face a problem: the phone charges 2-3 times slower than the declared 18 W. If the battery was filled in 2 hours, and now the process stretches for 4-5, there may be more than a dozen reasons - from banal wear of the cable to hidden errors of power consumption MIUI.

In this article, we will not only list possible problems, but also show how to diagnose them yourself (including hidden settings Redmi 9T), what tests to run, and what to do if even the original power supply does not save.

1. Problems with charger or cable

To start with, 90% of slow charging is due to a faulty charger or cable. Redmi 9T supports Quick Charge 3.0 (18 watts), but you have to meet three conditions:

• 🔌 Use the original power supply (or certified support analogue) QC Counterfeiting often only produces 5-10 watts.
• 📱 The cable should be USB Type-C → Type-C with support USB 2.0 (or higher) Older microUSB cables are physically unable to transmit more than 2 A current.
• ⚡ Port port USB The power supply should be yellow or orange in color – this is a standard sign of support for fast charging.

How do you check?

1. Get Redmi on board. 9T to the charger and look at the battery icon: if lightning burns ⚡ — Accelerated charging, if not, the device receives ≤10 Watts.
2. Install the AccuBattery app (free on Google Play) and check the input current in the Charging section. Norm for QC 3.0 - 1.5-2.5 A.

⚠️ Warning: If you use wireless charging, the speed will always be lower – Redmi 9T Does not support fast wireless charging (maximum 5-7 watts).

Battery wear: how to check and what to do

The Redmi 9T battery can run 500 to 800 full charge cycles, and then the capacity starts to fall and the charging time goes up.

• 📊 B Settings → Battery → Battery status (if this option is available in your firmware).
• 🔋 Through the app CPU-Z (battery → Good is normal, Replace soon is time to change.
• 📉 In AccuBattery, if the estimated capacity is below 80% of the factory capacity (4800 mAh instead of 6,000), the battery degrades.

What do I do?

• 🔄 If you wear 30-50%, try calibration: discharge the phone to 0%, then charge to 100% without interruptions (2-3 cycles).
• 🛠️ With wear and tear. >60 percent is just a battery replacement. ~1500–2000 ₽, analogue ₽. Important: Use a battery with an articular MB11 (for Redmi 9T).

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If the battery is still being recharged slowly after the battery is replaced, reset Settings → System → Resets → Resets all settings (without deleting data) This will reset the power controller calibration.

3. overheating of the phone during charging

The Redmi 9T is equipped with a Snapdragon 662 processor that warms up under intense load, and if the body temperature exceeds 40-45°C, the system automatically reduces the charging current to 1-1.5A to protect the battery.

• 🔥 Games or heavy applications (e.g. Genshin Impact, PUBG) while charging.
• ☀️ Charging under direct sunlight or in a stuffy room.
• 📱 Case blocking heat transfer (especially silicone or thick bumpers).
• 🛠️ Clogged radiator (dust in the charging connector or under the back cover).

How do you check the temperature?

1. Install AIDA64 (Sensors section) Charging normal is 30-38°C.
2. Or use the code: dial in the phone application ##4636## → Battery information → Temperature parameter.

⚠️ Warning: If the temperature rises above 50°C, turn off charging immediately! this could cause the battery to bloat or the power controller to shut down.

Remove the case |Close all applications |Transfer the phone to a cool place |Use the original charger |Do not play while charging-->

4. Program errors and bugs MIUI

The Redmi 9T runs on MIUI 12/13, where there are several known charging bugs:

• 🐞 Power controller error: After a firmware update, the system can limit current to 1 A even if used QC 3.0.
• 🔄 Background activity: Some system processes (e.g. com.miui.analytics) consume up to 20% charge per hour, interfering with fast charging.
• 📵 Charging lock: If the phone is connected to the PC in file transfer mode, the current can drop to 0.5 A.

How do you fix it?

1. Reset the battery settings: Settings → Annexes → Application management → Three points (⋮) → Resetting application settings → Drop it.
2. Disable MIUI Analytics: Settings → Privacy → Special Permits → Analytics → Disable
3. Update the firmware to the latest version (relevant for Redmi 9T - MIUI 14 based on Android 12).

5. Damaged USB Type-C connector

The Redmi 9T USB Type-C connector is one of the most vulnerable points.

• 🔌 Oxidized (due to moisture or sweat).
• 🛠️ Bending when the cable is not properly connected.
• 🧲 Contaminated with dust or pile from your pocket.

How do you check?

1. Light a flashlight in the connector: contacts should be clean and smooth.
2. Try to sway the cable slightly in the connector - if the charging current jumps (see in AccuBattery), the problem is in the contacts.
3. Connect the phone to the PC: if it is not detected or permanently disconnected, the connector is faulty.

Decisions:

• 🧹 Clean the connector with a toothpick (carefully!) or compressed air.
• 💧 If there is oxidation, wipe the contacts with an alcohol solution (90%+).
• 🛠️ In case of mechanical damage - only replacement of the connector (cost) ~1000–1500 ₽).

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If, when connecting the cable, the phone identifies it as a "charger" (without lightning). ⚡), The problem is exactly in the connector or cable. - Not in the power supply!

6.Background processes and energy efficiency optimization

MIUI aggressively optimizes background processes, but sometimes it works against the user.

• 📱 The phone is warming for no reason.
• 🔄 The battery is now charged, then discharged (graph in AccuBattery is similar to "saw").
• 🚫 Charging interrupted by 80-90%.

- background problems are to blame.

How do you fix it?

1. Turn off auto-update apps: Google Play → Settings → Auto-update apps → Never
2. Stop background activity for unnecessary apps: Settings → Apps → Select App → Battery → Limit background activity
3. Turn on the plane mode for the time of charging (if you do not need the Internet).

Pay special attention to the annexes:

• 📷 TikTok, Instagram – constantly sync data.
• 🎮 Game launchers (Xiaomi Game Turbo, GSpace).
• 📌 Messengers with active chats (Telegram, WhatsApp).

7. Failure of the power controller

The power controller (PMIC) in the Redmi 9T is responsible for distributing current between the battery and the phone's components, and if it fails, the symptoms are:

• ⚡ Phone does not charge above 1% or shows an incorrect percentage.
• 🔋 Charging is only in the off state.
• 🛠️ When the charger is connected, the phone is rebooted.

How do you diagnose?

1. Try charging your phone when it's off. If it's charging normally, the software is the problem.
2. Check the voltage at the contacts of the battery multimeter (should be 3.7-4.2 V).
3. If nothing works, bring it to the service. Controller repair costs between 2000 and 3,500. ₽.

⚠️ Warning: If after a fall or impact the phone stopped charging, do not try to disassemble it yourself! PMIC It may lead to a short circuit.

8.External factors: network, humidity, magnetic fields

Sometimes the problem isn't the phone.

• 🌡️ Ambient temperature: at <10°C or >35°C charging slows down.
• 💧 Humidity: Condensate in the connector or on the board can block current.
• 🧲 Magnetic fields: Do not put your phone on wireless charging, microwaves or magnet speakers.
• ⚡ Power grid quality: if the voltage in the socket is below 200 V, the power supply will not give 18 W.

Advice:

• Use a network filter to stabilize the voltage.
• Do not charge your phone in the bathroom or kitchen (due to steam).
• If you live in a region with frequent voltage drops, buy a UPS (uninterruptible power supply) for charging.

FAQ: Frequent questions about Redmi slow charging 9T