Xiaomi Redmi 8
fast-charging 18W
Redmi 8
In this article, we will discuss all official and alternative methods of activating fast charging, including hidden MIUI settings, charger and cable requirements, and typical errors that prevent the function from working correctly. Importantly, on some firmware, the option is hidden in the engineering menu - it requires caution to enable it so as not to disturb the stability of the system.
If you’ve tried to connect your smartphone to a charger from a Redmi Note 8 Pro or another Quick Charge 3.0 device, but nothing has changed, don’t be quick to blame the technical limitations. 80% of the time, the problem is solved software-based, without going to the service center. Next, you’ll find step-by-step instructions for different scenarios, including when fast charging suddenly stopped working after the MIUI update.
1. Checking the compatibility of the charger and cable
Before digging into your smartphone settings, make sure your charger and cable physically support fast charging. Xiaomi Redmi 8 is equipped with Quick Charge 3.0 technology, but it requires:
- 🔌 Power supply unit with power output at least 18W (9V/2A or 12V/1.5A). The original adapter from Redmi Note 8/9 fit perfectly.
- 🔗 Cable USB Type-C with support for high-speed data transfer (usually marked as "USB 2.0 High-speed" or "USB Low-cost cables often limit current.
- 📱 A faulty connector on a smartphone, and oxidizing or contaminating the contacts can cause power to drop.
How to check the power of the charger? On the original Xiaomi adapters, the parameters are indicated on the label (for example, 5V≈2A / 9V≈2A). If you have an unlabeled power supply, use the Ampere app (available on Google Play) - it will show the real charging current. For fast charging, the value should exceed 1500 mA when connected to the socket.
⚠️ Note: Use of uncertified chargers with declared power 18W+ Xiaomi recommends using only original accessories or certified analogues (for example, from Anker or Baseus).
If your charger meets the requirements, but the smartphone still charges slowly, move to the next section – perhaps a problem in the software settings.
2. Enable fast charging via MIUI settings
In standard MIUI firmware for Redmi 8, the fast charging option can be hidden or disabled by default to activate it:
- Open Settings → Battery and Performance.
- Slip on Battery Settings (or additionally, depending on the MIUI version).
- Find the Quick Charge option (could be called Accelerated Charge or Quick Charge) and turn on the switch.
If you don't have one, your MIUI version doesn't support manual control, in which case you can try upgrading to the latest stable version:
- Go to Settings → About the phone → System update.
- Click Check Updates and install available updates.
Make a backup copy of the data|Connect your smartphone to Wi-Fi|Charge the battery at least 50 times%|Make sure you have 1.5 GB of free space-->
After the update, check for the quick charging option again. If it never appears, go to the method with the engineering menu (section 4).
3.Why can fast charging not work?
Even with the right settings and a compatible charger, the function can fail. Consider typical causes and solutions:
| Problem. | Possible cause | Decision |
|---|---|---|
| Charging is in standard mode (5W) | Power saving mode is on | Turn off the settings → Battery → Power saving mode |
| The phone is warming up and reducing current | Overheating of the battery or processor | Let the device cool, remove the case, avoid direct sunlight |
| Fast charging only works up to 80% | Battery Protection Algorithm in MIUI | This is normal behavior – after 80% the current automatically decreases. |
| The function is available, but the speed does not change. | Failed power controller | Contact the service center for diagnosis |
Pay special attention to temperature, and if the smartphone heats up above 40°C during charging, the system will force the current to 5W to prevent battery degradation, in which case it will help:
- 🧊 Using charging in a cool room.
- 📵 Disabling resource-intensive applications (games, navigators) during charging.
- 🔄 Rebooting the device before connecting to the network.
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If you charge your smartphone frequently on the go, avoid using cheap power banks. Most external batteries do not support Quick Charge 3.0, even if the power is claimed to be high.
Activation of fast charging via the engineering menu (for power users)
If standard methods don't work, you can try to turn on the function through a hidden engineering menu. Attention: wrong actions in this section can lead to malfunctions of the smartphone.
Instructions:
- Open the Phone app and enter the combination: ##4636##.
- In the menu that appears, select Battery Information.
- Check the Charging Technology bar. If it says Standard, tap it and select Quick Charge (or Fast Charge).
- Save the changes and restart the device.
Some firmware may have different paths. Alternatively,
- Install the MTK Engineering Mode app (available on Google Play for MediaTek-based devices).
- Go to the Hardware Testing → Charging section.
- Activate the Fast Charging option and apply the settings.
⚠️ Attention: On some custom firmware, changing the settings in the engineering menu can lead to a blocking of charging altogether.If after manipulation the smartphone stopped charging, reset the settings through Settings → System system → Resetting settings.
What to do if the engineering menu is not opened?
5. Alternative methods of accelerating charging
If you do not enable fast charging software failed, you can optimize the process in other ways:
1. Background processes off
Close all applications before charging or activate Do Not Disturb (Settings → Notifications → Do Not Disturb) this will reduce the load on the processor and reduce heating.
2. Use of aviation mode (flight mode)
Activation of flight mode (Settings → Connections → Flight mode) turns off Wi-Fi, Bluetooth and cellular communication modules, which reduces charging time by 15-20%.
Calibration of the battery
If the battery is lying about the charge level (for example, jumps from 80% to 100%), perform the calibration:
- 🔋 Discharge your phone before automatically shutting down.
- 🔌 Connect to charging and wait 100% (do not turn on!).
- 🔄 Turn off the power, turn on the smartphone and recharge to 100%.
4. Resetting settings to factory
If the problem occurs after the MIUI update, reset via Settings → System → Reset. Pre-save data!
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Flight mode is the safest way to speed up charging without risking battery life, and reduces power consumption by 30-40%, allowing you to gain interest faster even on a standard 5W charge.
6.Frequent myths about the Redmi 8's fast charging
There are many misconceptions about how fast charging works on Xiaomi Redmi 8.
Myth 1: “Fast charging ruins the battery in 6 months.”
✅ Reality: Modern lithium-polymer batteries are designed for 500-800 Xiaomi uses algorithms that automatically reduce current at high temperature or above charge. 80%. The main thing is not to keep your phone on charging for days.
Myth 2: “You need to discharge your phone to 0% before charging.”
✅ Reality: Full discharge is more harmful than frequent recharging.Optimum range for lithium-ion batteries — 20-80%. Complete discharge accelerates battery degradation.
Myth 3: “Wireless charging is faster than wired charging.”
✅ Reality: Maximum wireless charging power for Redmi 8 — 10W (against 18W Even with Qi support, it's going to be slower.
Myth 4: “If you turn on fast charging, the phone will warm up and explode.”
✅ Reality: Redmi 8 has a power controller that turns off fast charging when overheated.The risk of explosion is reduced to zero if you use the original accessories.