How to turn off fast charging on Xiaomi Redmi 9T: all the ways and consequences

Xiaomi Redmi 9T

18W

All working ways to turn off fast charging

Redmi 9T

Controlling charging is an important aspect of extending battery life. Manufacturers rarely give users complete freedom to adjust their power consumption, but there are a few loopholes in Xiaomi's case. The key is to understand that turning off fast charging doesn't always mean increasing battery life. Sometimes slow charging under the wrong conditions (like in the heat) is even more harmful. Next are detailed instructions and expert advice.

Why do users want to turn off fast charging?

The main reason is the myths and real risks associated with the degradation of lithium-ion batteries. Fast charging does heat the battery more, and high temperatures accelerate wear. However, modern smartphones, including the Redmi 9T, are equipped with thermal control systems that limit current when overheated.

Here are the key arguments for and against shutdowns:

• 🔋 Pros of shutdown: less body heat, potentially slower battery degradation under the right conditions, the ability to charge your phone overnight without the risk of overheating.
• ⚡ Cons: increased charging time (c) ~2 hourly 4-5 hours), possible inconvenience in case of urgent need for energy, the risk of "training" the battery to slow current (controversial point).
• ⚠️ Neutral Fact: on Redmi 9T a battery with a capacity of 6000 mAh is used - its life depends not so much on the charging speed, but on the total number of cycles and temperature regime.

Interestingly, some users turn off fast charging not because of the battery, but for other reasons:

• 📱 To reduce the load on the power supply (especially if a non-original adapter is used).
• 🌡️ To reduce the body temperature during games or heavy use.
• 💤 To charge your phone at night without the risk of overheating (although modern smartphones automatically turn off fast charging when you reach 100%).

Method 1: Disconnect via standard settings (MIUI 12/13/14)

The easiest and safest method is to use the built-in MIUI options. Unfortunately, in recent firmware versions, Xiaomi has removed the direct fast charging switch, but it can be returned through hidden settings.

Instructions for Redmi 9T:

1. Open Settings → Battery and Performance.
2. Slap the icon. ⚙️ (gear) in upper right corner.
3. Select the Battery Settings item.
4. Scroll down and find the Quick Charge option (can be called Quick Charge or Turbo Charging).
5. Move the slider to the off position.

If you don't have Fast Charging, don't worry. In some versions of MIUI (especially on the Redmi 9T with global firmware), this option is hidden, and one of the following ways will help.

Method 2: Use of an engineering menu (for power users)

If the standard settings do not allow you to turn off fast charging, you can use the Engineering Mode, which requires caution, since improper actions can lead to malfunctions in the phone.

Step-by-step:

1. Open the Phone app and enter the combination: ##4636##.
2. In the menu that opens, select Battery Information.
3. Scroll down and find Fast Charge Config or Quick Charge.
4. Then, tap it and select Disable.
5. Reboot your phone to make the changes take effect.

⚠️ Note: On some versions MIUI The engineering menu may not have options to turn off fast charging, and after updating the firmware settings may reset.

An alternative way to get into the engineering menu:

• Install the MTK Engineering Mode app (available on Google Play for Mediatek processor devices).
• Open it and go to the Hardware Testing → Charging section.
• Find the Fast Charging option and turn it off.

Method 3: Applications for charging control (without root)

If you don't want to dig into the settings, you can use third-party utilities, which don't turn off fast charging at the system level, but they allow you to limit the charging current by simulating slow power.

Top.-3 tested applications:

How do these apps work? They don't shut down fast charging completely, they limit the current consumed at the software level. For example, AccuBattery can reduce the charging speed to 500 mA, which is 3-4 times slower than standard fast charging. Minus — the phone will charge longer, but without overheating.

⚠️ Attention: Some applications (e.g, 3C Toolbox requires ADB-You can have a full-time license, and you can't have a full-time license, and you can have a limited functionality, and you can reset your phone once you've rebooted.

Method 4: Use of a non-original charger

The most radical but working method is to use a power supply that does not support fast charging protocols, such as a charger from an old smartphone on a 5V/1A or 5V/2A.

How it works:

• 🔌 The original adapter Xiaomi (18W): Automatically activates fast charging if the phone supports it.
• 🔌 Old. USB-block (5W): Charges the phone in standard mode, without acceleration.

Advantages of the method:

• ✅ Suitable for any version MIUI.

Disadvantages:

• ❌ You need to have a second power supply on hand.
• ❌ Non-original chargers can damage the battery with prolonged use.
• ❌ The charging time increases to 5-6 hours.

💡

If you frequently charge your phone from a laptop, use it. USB-port-marked SS (SuperSpeed – These usually deliver higher current (up to 900mA) compared to standard ports (500mA).

The impact of fast charging off on the battery: myths and reality

Many users believe that turning off fast charging is guaranteed to extend the life of the battery, but it's actually more complicated.

• ⚡ Voltage: Fast charging uses higher voltage (9V/12V against 5V), It's a theoretically faster degradation, but in practice, the difference is minimal when used properly.

Research (including from Battery University) shows that the optimal mode for battery life is:

• Charging in the range of 20-80%.
• Avoid overheating (do not charge in the sun or during games).
• Use of original or certified adapters.

Turning off fast charging on the Redmi 9T makes sense only in three cases: if you charge your phone in extreme conditions (heat/cold), use an unoriginal adapter or leave the device on charge for the night.

💡

The main conclusion: The charging speed affects the battery much less than the temperature and depth of discharge. If you follow these parameters, you don't have to turn off fast charging.

Frequent Mistakes and How to Avoid Them

When trying to turn off fast charging, users often encounter problems, and here are the most common errors and solutions:

Another common problem is that the phone doesn't hold the settings after it's restarted, and that's because some of the parameters on the engineering menu are reset.

• Use apps with auto-start (e.g. AccuBattery with Auto-start option).
• Set up Tasker or MacroDroid to automatically limit current when connecting a charge.

⚠️ Warning: If after manipulating the settings, the phone began to discharge faster or does not turn on - reset the battery settings through Settings → Annexes → Application management → Three points. → Resetting the application settings, which will bring back the standard charging parameters.

FAQ: Answers to popular questions