Xiaomi Mi Band 4 remains one of the most popular fitness bracelets due to its combination of affordable price, functionality and long life. However, even such a reliable device has a weak point: the battery. Incorrect charging can shorten its life or even render the bracelet out of action. In this article, we will examine all the nuances of charging, from choosing a charger to extending the life of the battery.
You will learn how to avoid common mistakes (such as using unoriginal charges), what to do if the bracelet is not charging, and how to store the device properly so that the battery does not degrade, and why the Mi Band 4 can suddenly discharge in a few hours and how to fix it.
1.What is the right charger for Xiaomi Mi Band 4?
The first thing to start with is choosing the right charger, the Mi Band 4 comes with the original magnetic charging cable with a USB-A connector, but many users lose it or try to use alternatives. Let's figure out what you can and can't do.
The original cable is the best choice, as it provides stable voltage and protection against overheating, but if it is lost, there are several proven alternatives:
- 🔌 Original cable from Mi Band 5/6 — It is suitable because the connector is identical, but an adapter may be required for the USB-C, If you have a modern power supply.
- 🔋 Third-party certified charging, such as from the Baseus or Anker brands, but only with a magnetic connector for the Mi Band.
- ⚠️ Unoriginal cables without certification – can damage the battery due to unstable current.
Important: Mi Band 4 does not support wireless charging, despite rumors on the Internet. Any adapters for Qi charging are incompatible and can burn the device board.
⚠️ Warning: Never use chargers with an output current greater than 1A. High current accelerates battery degradation and can lead to overheating.
2. Step-by-step instructions: how to charge the Mi Band 4
The charging process seems simple, but many users make mistakes that shorten battery life. Follow this instruction to charge the bracelet correctly:
- Disconnect the strap from the bracelet body. To do this, pull the lock on the back side and carefully remove the capsule.
- Connect the magnetic charging cable connector to the contacts on the back of the Mi Band 4. Make sure the connection is tight - a click should be heard.
- Connect the other end of the cable to the power supply. USB-port or adapter with output 5V/1And.
- Wait for the charging indicator to appear on the bracelet screen (battery icon with lightning animation).
If the indicator does not appear, check:
- 🔌 Density of the magnetic connector.
- 🔋 Possibility of work USB-port.
- 📱 Cleanliness of contacts on the bracelet (if necessary, wipe them with an alcohol napkin).
Disconnect the strap from the body | Check the purity of the contacts |Use the original cable |Connect to the source 5B/1A|Wait for the charging indicator-->
The average full charge time is 1.5-2 hours. If the bracelet is completely discharged, the process can take up to 2.5 hours. It is not recommended to interrupt charging at half - this can lead to incorrect determination of the battery level in the future.
3.How much does the Xiaomi Mi Band 4 charge hold?
The official specs of the Mi Band 4 promise up to 20 days of battery life, but the actual life span depends on the intensity of use.
| Mode of use | Time to work. | Notes |
|---|---|---|
| Minimum activity (time only) | 25-30 days | Notifications, backlights, heart rate disabled |
| Standard mode (notifications, pedometer) | 14-18 days | The screen is turned on when lifting your hand, synchronization 1 time a day |
| Intensive use (sports, pulse 24/7) | 7-10 days | Continuous monitoring of heart rate, GPS-tracker (if connected) |
| Always on mode (display does not go out) | 2-3 days | Maximum battery consumption is not recommended |
If your bracelet discharges faster than the table indicates, the problem may lie in:
- 🔋 Degraded battery (if the device is more than 2-3 years old).
- 📱 Constant sync with your phone (turn off automatic sync in Mi Fit settings).
- 🌡️ Extreme temperatures (below 0)°C or higher than 40°C).
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To extend the life of the battery, once a month completely discharge the bracelet before turning off, and then charge to 100%.
4. Why is the Mi Band 4 not charging? problem solving
If the bracelet doesn't respond to the charger connection, don't panic. 90% of the time, it's self-solving. Let's look at the most common causes and ways to fix them:
Contact problems
Over time, the contacts on the bracelet or charging cable may become oxidized or contaminated. Wipe them with an alcohol solution (at least 70%) and soft cloth. Don't use abrasive materials - they will damage the coating.
Faulty cable or adapter
Try another cable or USB-If the bracelet starts charging, the power supply is a problem. Xiaomi's original cables rarely fail, but cheap ones often break down after 3-6 months.
Programmatic failure
Sometimes the bracelet freezes and doesn't show the charging indicator, when it's actually charging.
- Connect the bracelet to charging and leave for 30 minutes.
- If the screen does not respond, reset your settings through the Mi Fit application (Device Profile → Reset).
Bloated battery
If the body of the bracelet is deformed or has a characteristic smell, immediately stop using. This is a sign of bloating of the battery, which is dangerous for health, in which case a replacement of the battery at the service center is required.
⚠️ Warning: If the bracelet is heated during charging (more than 45)°C, turn it off and check the cable. Overheating can cause fire!
What to do if the bracelet is charged, but discharged quickly?
5. How to extend the life of the battery Mi Band 4?
The lithium polymer batteries used in the Mi Band 4 degrade over time, but proper care can slow this process.
- 🔋 Avoid full discharge - try to charge the bracelet at 20-30% charge. Deep discharges reduce battery life.
- 🌡️ Store at room temperature – ideal range: 10–30°C. Do not leave the bracelet in the sun or in the cold.
- ⚡ Don't hold on charging for long - after reaching 100%, turn off the bracelet. Overcharging is harmful to lithium-polymer batteries.
- 📵 Turn off unnecessary features — such as constant heart rate monitoring or notifications from underutilized apps.
It is also useful to update the bracelet firmware through the Mi Fit app. Newer versions often optimize power consumption. To check the relevance of the firmware, go to the Device Profile → Firmware Update.
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The optimal battery life level is 30 to 80 percent, and keeping the battery in this range increases its lifespan by 30 to 50 percent.
6.Can I charge Mi Band 4 from Power Bank?
Yes, the Mi Band 4 can be charged from an external battery (power bank), but with reservations:
- ✅ Suitable Power Bank: With Exit 5V/1A or 5V/2A (but no more!) with voltage stabilization support (e.g. Xiaomi Mi Power Bank or Anker PowerCore).
- ❌ Power Bank: Quick Charge (Power Bank, PD) — They can deliver too high voltages. Cheap no-name models with no overload protection.
If you travel frequently, bring your original cable and power bank labeled 5V=1A. Avoid charging in the cold (such as in a tent in winter) – this can cause battery problems.
7. Alternative charging methods (in extreme cases)
If you don't have the original cable, but you need to charge the bracelet urgently, you can use emergency methods, but remember, they are risky and can damage the device.
7.1 Charging from another Mi Band
If you have a Mi Band 3/5/6, you can gently connect its cable to the Mi Band 4, and the key is to make sure the contacts match. Don't force it so you don't bend the connector.
Homemade adapter
On the Internet you can find schemes for making a charger from USB-But this method requires soldering skills and an understanding of the electrician, and the risk of damaging the bracelet is very high, and only use it in a desperate situation.
⚠️ Never connect Mi Band 4 directly to the USB-The 5V voltage can burn the power controller!