Why Xiaomi Smartphone Is Slowly Charging: A Complete Analysis of Causes and Solutions

Introduction: When “fast charging” works like a turtle

Did you plug a Redmi Note 12 or POCO X5 into charging in the evening and the battery barely reached 50% in the morning? Or did the Xiaomi 13T with 120W HyperCharge suddenly charge for more than an hour? Slow charging is one of the most annoying issues that can arise on both new and old smartphones of the brand. Causes range from banal battery wear to hidden MIUI firmware bugs.

In this article, we will not only list the possible culprits of braking, but also show you how to diagnose the problem yourself without going to the service center. You will learn what hidden MIUI settings affect the charging speed, how to check the battery health through the engineering menu, and why even the original power supply can work half-heartedly.

Spoiler: 60 percent of the time, it's not the smartphone itself that's to blame, but external factors, from poor-quality cables to overheating of the processor, but everything in order.

1. Battery wear: the main cause of slow charging

The lithium-polymer batteries in Xiaomi smartphones degrade over time, which is a physical process. After 300 to 500 full charge cycles, battery capacity decreases by 20 to 30 percent, and with it, the rate of energy replenishment decreases, especially on models older than 2 years: Redmi Note 9 Pro, Mi 10 or POCO F2 Pro.

How to check battery wear without third-party applications?

• 🔋 Enter the code ##4636## in the phone app, then select Battery Information. The Wear Level (or Battery Health) option will show the current state of the device.
• 📊 V MIUI 14+ Go to Settings. → Battery → Battery status. If the capacity has dropped below 80 percent of the original capacity, it's time to think about replacing it.
• ⚡ Use the AccuBattery app (available on Google Play) to show real capacity and charging speed in mAh.

Not only does critical battery wear slow charging, it also causes sudden shutdowns at 20 to 30 percent of the charge. If your Xiaomi shuts down in the cold or when it’s under heavy load, it’s a sure sign that the battery needs to be replaced.

⚠️ Note: Some models (e.g. Xiaomi) 12S Ultra artificially restricts the charging current when the battery wears more than 25%, which is protection against overheating, but the user feels that the smartphone has broken».

2. Unoriginal or damaged chargers

Xiaomi is known for its accessories ecosystem, but not all are equally useful. Cheap cables and power supplies from unknown brands can not only slow charging, but also damage the smartphone’s power controller, especially for models with fast charging (33W/67W/120W).

How to distinguish the original charger from the fake:

Even the original power supply can fail over time, and it's easy to check if it works.

1. Connect the charger to another smartphone (preferably the same brand).
2. Use it. USB-Tester (e.g. Xiaomi) USB Tester 2) for measuring current.
3. Check the cable for insulation overburden or damage.

⚠️ Note: If you use wireless charging for Xiaomi 13/14 Remember: maximum wireless charging power — 50W, what 2–3 It's normal, not a breakdown!

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If you have a POCO F5 or Redmi K60 with 67W support, but you're charging on 18W, try turning on Ultra Fast Charging in your battery settings, which sometimes resets after you update your MIUI.

3. Software limitations: MIUI inhibits charging

MIUI has several hidden features that can artificially limit charging speeds. For example, Optimized Charging (or Adaptive Charging) mode slows the process after 80% to keep the battery healthy. Useful for durability, but uncomfortable if you need to charge your phone urgently.

Where to disable restrictions:

• 🔄 Go to Settings. → Battery → Battery settings.
• 🛑 Disable options: Optimized charging (or Adaptive Charging) Battery protection (in some firmware) Charging restriction (if any)
• 🔋 For Xiaomi. 12/13/14 Check the series settings → Additionally. → Special facilities → Optimizing the battery.

Another common problem is the background processes that load the processor while charging, such as updating apps via Google Play or syncing Mi Cloud, to avoid this:

1. Turn on the plane mode during charging.
2. Close all applications through recent tasks.
3. Turn off automatic software updates in Settings → About phone → System update.

4.Overheating: Why a smartphone "strangles" charging at high temperatures

Xiaomi is actively using thermal throttling - automatic reduction of performance (and charging speed) when overheated. The normal operating temperature of the battery is 15-35 ° C. If the smartphone heats up above 40 ° C, the power controller forcibly reduces the current.

The main causes of overheating during charging:

• 🔥 Games or heavy apps (like Genshin Impact or Call of Duty Mobile).The Snapdragon 8 Gen 2 processor in Xiaomi 13 Ultra can heat up to 50°C in 10 minutes of play.
• ☀️ Charging under direct sunlight or in a stuffy room.
• 🔌 Using your smartphone while charging (especially with Always On Display enabled).
• 🚫 Connector pollution USB-C dust or debris (deteriorates heat sinking).

How to avoid overheating:

1. Remove the case (especially silicone or thick armored case).
2. Use the charger in Airplane Mode.
3. Do not put the phone on soft surfaces (cushion, blanket) - this blocks ventilation.
4. For gaming smartphones (Black Shark 5, POCO F4 GT) use active cooling (e.g., Xiaomi Game Cooling Fan cooler).

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If the smartphone heats up to 45°C or higher, charging can stop completely before cooling down.

5. Problems with USB-C connector or power controller

Mechanical damage to the USB-C connector is one of the most insidious causes of slow charging, and dust, contact oxidation, or bent pins can lead to unstable connections, causing the smartphone to constantly “lose” and restore charging, which not only slows down the process, but also increases battery wear.

How to diagnose a problem with the connector:

• 🔍 Light a flashlight into the connector – if dust, debris or bent contacts are visible, cleaning is required.
• 🔌 Try to shake the cable in the connector. If you get a charge, it goes away - the problem is contacts.
• 📱 Connect your smartphone to your PC, and if you're interrupted, it's the connector or the cable.

Cleaning the connector can be carried out independently:

1. Turn off the phone and remove it. SIM-map.
2. Use a wooden toothpick (not metal!) to remove debris.
3. Wet the cotton swab in isopropyl alcohol (90%+) and gently wipe the contacts.
4. Let the connector dry for 10-15 minutes before connecting.

If the cleaning didn't work, the power controller might malfunction (e.g., Qualcomm's PMIC chip in Snapdragon smartphones), which would require repairs at the service center.

• 🔋 The phone is charged only when it is off.
• ⚡ Charging is jerky (0%, then 100% current).
• 💥 Smartphone suddenly turns off when connecting charging.

6 MIUI Updates and Setting Resets: When Software Is to Blame

After major MIUI updates (e.g., 13-to-14 version), users often complain about slowing down charging.

• 🐛 Bugami in firmware (especially in the first builds).
• 🔄 Resetting battery optimizations.
• 📱 Conflicts with user settings.

How to return normal charging speed after the update:

If the problem occurs after the update, try:

1. Reverse to the previous version of MIUI via Fastboot (instructions are available on the XDA Developers forum).
2. Reset your phone to factory settings (Settings → Restore and Reset → Reset settings).
3. Install a custom core (e.g., FrancoKernel for POCO F3) if you are an experienced user.

Sometimes it helps to simply reflash through Recovery:

1 Download the latest stable firmware for your model from https://new.c.mi.com/global/miuidownload/index.


2. Rename the file to update.zip and place it in the root of the phone's memory.




3. Go to Recovery: Turn off the phone, then press Power + Volume Up.




4. Select Install update.zip and confirm.

⚠️ Note: On some models (Redmi Note 11, POCO X3 Pro) after resetting, Fast Charging is re-activated in the battery settings. Without this, the smartphone will charge on the battery. 10W no matter the power supply.

External factors: from network filters to magnetic interference

Even if the smartphone is fine, external conditions can slow down charging.

• 🔌 Network filters and extension cords, many cheap filters can't withstand the load of fast charging (67W/120W) and limit current.
• 🌡️ Low temperature, when charging in the cold (< 10°C) Xiaomi automatically reduces current to protect the battery.
• 🧲 Magnetic interference: Do not place your phone on metal surfaces or near powerful speakers.
• 📶 Weak network signal: In areas of poor coverage, the smartphone spends more energy searching for the network, which slows down charging.

How to minimize the impact of external factors:

• 🔌 Connect the charger directly to the socket, without extension cords.
• 🏠 Use network filters with voltage surge protection (e.g. Xiaomi Mi Power Strip).
• 🌡️ Charge your phone indoors at room temperature (20–25)°C).
• 📵 Turn on Airplane Mode if the network signal is weak.

FAQ: Answers to Frequent Questions