Disassembly Xiaomi Mi Band: how to remove the capsule, replace the battery or strap

The Xiaomi Mi Band fitness bracelets have long been one of the most popular wearables due to a combination of functionality, compactness and affordable price. However, even such a simple device sometimes requires repairs: whether it is replacing the battery after 2-3 years of use, recovering from moisture or replacing the strap. Unlike smartphones, disassembly of the Mi Band has its own nuances - there are no screws, and the body is glued to withstand sweat and moisture.

This article will help you understand how to properly open the Xiaomi Mi Band bracelet (relevant for models from Mi Band 2 to Mi Band 8), without damaging fragile latches and contacts. We will take a detailed look at the tools you need, the disassembly steps, and the typical errors that can cause the device to fail. Particular attention will be paid to the Mi Band 7/8 models, whose capsules have a unique mounting system that is easy to break when unguarded.

What Xiaomi Mi Band models can be disassembled independently

Not all versions of the bracelets are equally disassemblable.

• 🔧 Mi Band 1/1S is the easiest to disassemble, but it's obsolete. It's attached to the latches without glue.
• 🔧 Mi Band 2-4 is a classic design with plastic latches and minimal adhesive, easy to disassemble with a mediator.
• ⚠️ Mi Band 5-6 -- added perimeter sealant, requires heating to soften the adhesive.
• ⚠️ Mi Band 7/8 -- the most complex ones are thin body, brittle latches and tight sealing, and the risk of damage is higher when disassembled.

If your bracelet is from the Mi Smart Band series (e.g. Mi Smart Band 6 Pro), the disassembly principles are similar but may differ in the location of the charging contacts. Newer models (2023-2026) often feature additional sensors (e.g. SpO₂) that attach to the board, which are easily damaged if unopened.

⚠️ Warning: Disassembling the Mi Band 7/8 without experience can damage the flexible plume connecting the screen to the board. If the goal is to replace the battery, consider buying a new capsule (cost ~1500–2500 RUB), as repairs may cost more.

Preparation for disassembly: tools and security measures

Before you start, make sure you have everything you need, and the absence of at least one tool can cause permanent damage.

• 🔨 Plastic mediator (or guitar mediator) - to separate latches.
• 🔥 Dryer or thermo-air station - for softening the adhesive (especially relevant for Mi Band 5-8).
• 🧲 Magnetic screwdriver (if the model has screws, for example, in some versions of the Mi Band 4 NFC).
• 📦 Small parts container – latches and screws are easily lost.
• 🧴 Isopropyl alcohol (90%+) — Cleaning contacts and removing glue residues.

Also prepare the workplace:

• 🪑 Work at a table with good lighting (better to use a desk lamp).
• 🧹 Put white cloth or paper on the table – this will help you not to lose small details.
• 📱 Have a smartphone on hand to capture the process (in handy when you build it back).

⚠️ Warning: If you are disassembling a battery replacement bracelet, pre-discharge it completely (up to 0%).This minimizes the risk of short circuits when the battery is disconnected. For models with NFC (e.g. Mi Band 4 NFC), disable the contactless payment feature in the Mi Fit app - after disassembly, the module may require re-activation.

Step-by-step: how to remove the capsule from the strap

The first step is to separate the electronic capsule from the strap, and in most Xiaomi Mi Band models, the capsule is fixed in the slots of the strap without screws, but there are nuances:

1. Place the bracelet on a flat surface with the screen down.
2. Find a small recess on the back of the capsule (usually next to the charging contacts), insert a plastic mediator and gently press the side of the strap.
3. Once the capsule is moved 1-2 mm, move the mediator along the body, releasing the latches in turn. Don't put too much effort - the latches are fragile!
4. Mi Band 7/8 models may require simultaneous pressing of two latches on both sides of the capsule (use two mediators).

If the capsule does not respond, try to heat the strap slightly with a hairdryer (temperature not higher than 60 ° C) - this will soften the plastic. Do not use metal objects (knives, screwdrivers) so as not to scratch the body.

Disassembly of the capsule: how to get to the battery and board

The most important step is to open the capsule itself, and the rule is patience and accuracy.

For Mi Band 2-4:

1. Place the capsule between two plastic mediators (top and bottom) and gently compress. The latches should disperse.
2. If the case does not respond, slightly heat it with a hair dryer (40-50 ° C) and try again.
3. And when you open it, you'll see a board with a battery, and the battery is usually glued, and you need to tap it with a mediator and disconnect the plume.

For the Mi Band 5-8:

1. Place the capsule on a hard surface and heat the hair dryer around the perimeter (60-70°C) for 1-2 minutes.
2. Put the mediator in the gap between the front and back of the body. Keep it gently along, disengaging the latches. Take your time, the latches are thin and break when you move sharply.
3. And when you open it, you'll see a flexible plume connecting the screen to the board, and you can't pull it off, you can just lift it up carefully.

In the Mi Band 7/8, the battery is often soldered to the board, and it will require a soldering iron with a thin stinger and experience with microelectronics, and if you don't have that experience, you should contact the service.

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Before disconnecting the battery, take a picture of the location of the plumes and contacts. When assembled back, this will help to avoid errors with the connection of sensors (for example, a pulsemeter or accelerometer).

Typical Disassembly Problems and How to Avoid Them

Even with a careful disassembly, you can get into trouble.

• 🔋 Battery damage -- if the battery is swelling, it can't be pierced or bent, it can cause fire, and you better dispose of it and replace it with a new one.
• 📱 Screen plume tearing is a common problem when disassembling the Mi Band 7/8. The plume is attached by fragile contacts that are easily torn off by the mediator.
• 💧 Moisture on board – if the bracelet has previously sunk, dry it in rice or silica gel for at least 24 hours before disassembling.
• 🔌 Oxidation of charging contacts -- cleaned with isopropyl alcohol and cotton swab. Don't use acetone!

If the bracelet is not turned on after assembly:

1. Check if the battery is connected correctly (plus to plus, minus to minus).
2. Make sure the screen plume is not bent and fits tightly to the connector.
3. Connect the bracelet to charge for 10-15 minutes – sometimes after disassembly, it takes time to “wake up” the power controller.

⚠️ Warning: If the Mi Band 7/8 stopped detecting pulse or steps after disassembly, the sensor contact probably went away. In these models, the sensors are attached to the board without soldering, so you can gently press them with your finger (but don't overdo it!).

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The key to disassembling is to take your time. 80 percent of the damage is caused by trying to pull the capsule out by force. Heat and plastic tools are your best tools.

Battery replacement: battery selection and installation nuances

The average battery life of the Xiaomi Mi Band is 2-3 years, after which the capacity drops by 30-50%, and the bracelet requires charging every 1-2 days, and replacing the battery is the most common reason for disassembly.

How to choose a battery:

• 🔍 For the Mi Band 2-4, a 100-110 mAh battery (original article: MDY-05-EJN) is suitable.
• 🔍 For Mi Band 5-6 – 125-135 mAh (Article: BL-5B).
• 🔍 For Mi Band 7/8 — 180 — 190 mAh (article: BTY-05-EJN).

When installing a new battery:

1. Clean the contacts on the board and battery with isopropyl alcohol.
2. Stick the battery onto double-sided scotch (use thin scotch for electronics).
3. Connect the battery plume to the board. Mi Band 7/8 models may require soldering.
4. Before assembly, check the voltage on the contacts with a multimeter - it should be in the range of 3.7-4.2 V.

If the bracelet discharges quickly after replacement, two reasons are possible:

1. Poor battery (check the seller, read reviews).
2. The power controller on the board is damaged (diagnosis with a multimeter is required).

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When buying a battery, pay attention to the date of production (indicated on the label) and batteries older than 6 months can already lose up to 20% of capacity.

Assembly of the bracelet after disassembly: step-by-step checklist

Reverse assembly is as important as disassembly. If you skip one step, the bracelet may fail to turn on or malfunction.

1. Make sure that all plumes (screen, sensors, battery) are connected tightly, without inflections.
2. Make sure the battery is securely fixed and does not hang inside the case.
3. So assemble the body by combining the latches. Start on one side and gradually snap around the perimeter.
4. For Mi Band 5-8 models, a thin layer of sealant (e.g., LOCTITE 577) can be applied along the edge of the body to restore moisture protection.
5. Install the capsule in the strap, making sure that the charging contacts match the holes.
6. Connect the bracelet to charge for 10-15 minutes, even if it doesn’t respond immediately.

After assembly:

• 🔄 Reset your bracelet settings via the Mi Fit app (Device Profile → Reset).
• 📱 Update the firmware to the latest version.
• 🔋 Completely discharge and charge the bracelet 1-2 times to calibrate the power controller.

⚠️ Warning: If the Mi Band 7/8 bracelet doesn't sync with your phone after assembly, check if the Bluetooth module is switched off. Sometimes the antenna will leave when you disassemble, in which case only soldering or a change of board will help.

FAQ: Answers to Frequent Questions