How to charge a smart watch Xiaomi Mi Band 4: full instructions with tips

Why Charging Is Important for the Mi Band 4

The Xiaomi Mi Band 4 fitness bracelet remains one of the most popular wearables due to its combination of affordable price, functionality and long battery life. However, even such a reliable device requires proper handling — especially when it comes to charging. Failure to follow basic rules can lead to rapid battery wear, unstable operation or even breakdown of the gadget.

In this article, we will examine not only the standard charging procedure, but also the nuances that are often ignored in official instructions, such as why you can not use chargers from other Mi Band models, how it affects the battery overheating or full discharge, and what to do if the bracelet stopped charging, and pay special attention to myths – for example, the popular belief that “the first charge should be done for 12 hours”.

If you have just purchased the Mi Band 4 or have been using it for a long time, but notice that the battery has become more quickly, this guide will help you avoid typical errors and prolong the life of your gadget.

Completement and original charger

In the box with Xiaomi Mi Band 4 comes a special charger, which is a small module with contacts and USB Type-A cable. This is not a regular microUSB or Type-C connector is unique and is only suitable for the Mi Band line (except for the newest models).

The original charger has the following characteristics:

🔌 Type of connector: proprietary magnetic connector (not compatible with other devices).
⚡ Tension: 5V, Current strength - up to 200 mA (maximum power) ~1 Watt).
📏 Cable length: ~20 cm (convenient to connect to power bank or laptop).
🛡️ Protection: built-in protection against overheating and short circuit.

If you lose the original charge, only buy certified Mi Band 4-labeled counterparts. Cheap fakes often don't meet current requirements, which leads to slow charging or overheating of the battery. Pay attention to the magnetic mount - the original has a secure fixation, and copies often have a backlash.

⚠️ Note: Do not use the Mi Band chargers 6/7 Or other models, even if they look similar, and the contacts may not match, and the voltage may differ, which will cause the bracelet to malfunction.

Next Next post: How to Charge Mi Band 4

The process of charging the bracelet is simple, but there are several nuances that will help to avoid problems.

Disconnect the strap from the bracelet body. To do this, pull the capsule towards the screen (direction is indicated by the arrow on the back).
Connect the charger to the contacts on the back of the case, and the magnets will help you to lock the position correctly, and you'll hear a slight click.
Connect the cable to the power source: USB-computer port, charging adapter (5V/1A) Do not use quick chargers (Quick Charge, VOOC etc. – they can damage the power controller of the bracelet.
The charge indicator (battery icon with animation) will appear on the bracelet screen. If the indicator is not on, check the density of the contacts.

Full charging time is 1.5-2 hours (0% to 100%). If the bracelet is not fully discharged, the process will take less time. While charging, you can use the basic functions (watching time, steps), but synchronization with the phone can work unstable.

Check the integrity of the cable and contacts

Disconnect the bracelet from your phone (by Bluetooth)

Use an original or certified RMS

Do not leave the bracelet charged in direct sun or near heat sources.-->

After reaching 100%, disconnect the bracelet from power. Prolonged stay on charging (more than 4-5 hours) can lead to overheating of the battery and shorten its life.

Optimal conditions for charging: what can and can not

The Mi Band 4 battery is a 135 mAh lithium polymer (Li-Po) battery, which is sensitive to extreme temperatures, deep discharge and recharge. To extend the life of the battery, follow these rules:

Parameter	Recommended values	What happens when you break it?
Ambient temperature	10–35°C	At <0°C or >40°C, the capacity drops, the risk of battery bloating
Storage charge level	40–60%	A deep discharge (0%) or 100% charge can damage the battery for a long time.
power supply	USB 2.0 (5V/1A) or computer	Fast charging or unstable sources reduce lifespan
Charging time after 100%	No more than 1 hour.	Overheating of the power controller, the risk of battery degradation

One of the most common myths is that the new Mi Band 4 has to be charged for 12 hours, which is an outdated rule for nickel batteries, and modern Li-Po batteries do not require "training," and in fact, long-term charging "on reserve" only harms the power controller, just charge the bracelet to 100% and turn off.

Another mistake is to charge the bracelet when it's on while it's actively synchronizing with the phone, which puts extra stress on the battery and can cause overheating, so you'd better turn off Bluetooth while you're charging or put the bracelet in flight mode.

Every 5-7 days

Every 2-3 days

Only when it's completely discharged.

Less than once in 10 days-->

Frequent problems and their solutions

Even when properly operated, Mi Band 4 users sometimes face charging problems, and consider the most common cases and ways to fix them:

Bracelet not charging

🔍 Check contacts: Clean contacts on the bracelet and charger with a cotton swab dipped in alcohol. oxidation or dirt can interfere with charging.
🔌 Try another one. USB-port: Sometimes the port of the computer or adapter does not give enough voltage.
🔄 Reboot the bracelet: Connect charging, then press and hold the touch button for 10-15 seconds until the Mi logo appears.
🔋 Check the battery: If the bracelet doesn’t respond to charging at all, it’s possible the battery has failed (especially if the device is over 2-3 years old).

The bracelet is charging too slowly.

The reasons may be as follows:

⚡ Uses a non-original charger with low current.
📱 Simultaneously, data synchronization with the phone (turn off Bluetooth while charging).
🔥 Overheating of the bracelet or charger (let it cool for 10-15 minutes).
🖥️ Connection to USB 3.0 (Blue Port) - Try it out USB 2.0 (black port).

Bracelet discharges quickly

If your autonomy has dropped to 1-2 days, check:

📲 Firmware updates: Outdated software may contain errors that lead to increased power consumption. Update the bracelet through the Mi Fit app.
🔔 Notifications: Frequent vibrations from messages and calls put the battery to a standstill.Configure the notification filter in Mi Fit.
🌡️ Date and time: If the bracelet is constantly synchronizing time, this may indicate a failure in the Bluetooth module.
🔋 Battery wear: After 300 to 500 charging cycles, battery capacity decreases by 20 to 30 percent, in which case only a battery replacement will help.

⚠️ Warning: If the bracelet heats up during charging or operation, immediately disconnect it from power.Overheating may indicate a malfunction of the battery or power controller - in this case, further use is dangerous!

What if the bracelet is not turned on after discharge?

If the Mi Band 4 is completely discharged and does not respond to charging, try this: 1. Connect the charging and leave for 30-60 minutes (sometimes it takes time to "wake up" the controller). 2. Press and hold the touch button for 20-30 seconds. 3. If it does not help, try charging from another source (for example, power bank instead of a computer). 4. In extreme cases, you may need to firmware through Mi Fit or contact the service center.

How to extend the battery life

The average battery life of the Mi Band 4 is 2-3 years when used actively, but with proper care, this period can be extended to 4-5 years.

🔄 Avoid full discharge: Charge the bracelet when the charge drops to 10-20%.Deep discharge (0%) severely damages Li-Po batteries.
⚡ Don't keep on charging for long: Once 100 per cent is reached, turn off power.Constant subcharge accelerates battery degradation.
🌡️ Keep it cool: If you don’t use it for a long time (for example, during a vacation), store it at a charge of 40-60% in a dry place at a temperature of 15-25°C.
📵 Turn off unnecessary features: Permanent pulsemeter, weather notifications and unused widgets reduce uptime.Configure them in Mi Fit.
🔋 Calibrate the battery: Every 2-3 months, let the bracelet discharge to 0% (until it shuts down), then charge to 100% without interruptions.

Another useful life hack is the use of energy saving mode.

Open the Mi Fit app.
Go to Profile → Mi Smart Band 4 → Screen and brightness.
Activate the option Power Saving Mode (disables the constant screen lighting).

This will increase your autonomy by 20 to 30 percent, especially if you don’t use lighting during the day.

💡

If you often forget to charge your bracelet, turn on the low charge notification in the Mi Fit (in the Notifications → Battery section) to help avoid a full discharge.

Comparison with other Mi Band models

If you are considering buying the Mi Band 4 or thinking about switching to a new model, it is useful to compare the charging features of different generations of bracelets:

Model	Type of charging	Charging time.	Battery capacity	Autonomy
Mi Band 3	Proprietary connector (different from the 4th model!)	2.5 hours	110 mAh	Up to 20 days.
Mi Band 4	Magnetic connector (unified for 4/5/6)	1.5 hours to 2 hours	135mAh	Up to 15-20 days.
Mi Band 5	Magnetic connector (compatible with the 4th model)	1.5 hours	125 mAh	Up to 14 days.
Mi Band 6	Magnetic connector (compatible with 4/5)	2 hours	125 mAh	Up to 14 days.
Mi Band 7	New Magnetic Connector (not compatible with Model 4)	1 hour	180mAh	Up to 15 days.

Note that the Mi Band 4 and Mi Band 5 chargers are interchangeable, but not compatible with the Mi Band 3 or Mi Band 7. If you are planning to upgrade to a new model, consider this when buying spare charges.

It’s also worth noting that despite the smaller battery capacity, the Mi Band 5/6 has comparable autonomy to the Mi Band 4 thanks to software optimization, but the Mi Band 4 remains the longest running model in the world.

FAQ: Answers to Frequent Questions

Can I charge Mi Band 4 from Power Bank?

Yes, but only if the power bank issues stable 5V/1A. Avoid powerful devices (10W They can damage the power controller of the bracelet, and it is also not recommended to charge outside at lower temperatures. 10°C or higher 30°C.

How many charging cycles does the Mi Band 4 battery hold?

The manufacturer claims about 500 full cycles (0% to 100%) to a noticeable decrease in capacity. In practice, when handled carefully, the battery lasts 2-3 years. After 300 cycles, the capacity usually drops by 20-30%.

Why does the bracelet show 100% charge, but quickly discharge?

This is a sign of battery wear or controller failure. Try calibrating the battery: discharge the bracelet to 0% (until it shuts down), then charge to 100% without interruption. If it doesn't work, you need to replace the battery.

Can I use the bracelet while charging?

Yes, but with reservations: the basic functions (time, pedometer) will work, but synchronization with the phone can be unstable.

What to do if the charger breaks down?

Buy an original replacement (Article XMSH07HM) or a certified magnetic connector. Don't use homemade solutions - this is dangerous for the bracelet. In extreme cases, you can try charging through the contacts with a multimeter (only for power users!).

💡

Charging from non-original devices is the main reason for premature wear of the Mi Band 4 battery. Always check the compatibility of the charger with your bracelet model.