How to disassemble Xiaomi 20000 mAh: detailed instructions with photos and tips

Xiaomi’s 20000 mAh superbanks are some of the most popular external batteries on the market due to their combination of capacity, compactness and reliability, but over time, even these can fail: to zero, battery bloating or breakage. USB-In such cases, disassembly of the device becomes necessary - whether for replacement of battery cells, repair of control boards or cleaning of contacts.

In this article, you will find step-by-step disassembly instructions tailored to the design of Xiaomi Mi Power Bank 20000 mAh (PLM03ZM, PLM05ZM, PLM06ZM and the like). We will look at what tools you need, how to avoid damage to the case, and what to do with hidden latches, which often break when you open the sloppy, and you will learn which elements inside you can replace yourself, and when to contact a specialist.

Warning: disassembly of the overbank is warranty-free (if it is still in effect) and requires caution - inside are lithium-ion cells that, if mishandled, can ignite. If you are not confident in your abilities, it is better to entrust the repair to the service center.

Preparation for disassembly: tools and security measures

Before you start, you need to get everything you need, and the lack of the right tools is the main cause of damage to the body or internal components.

• 🔧 Plastic mediators or shoulder blades (2-3 - To carefully separate the latches. Metal screwdrivers can leave scratches!
• 🔨 Cross screwdriver (usually) PH0 or PH1) — board-screw.
• 🧲 Magnetic mat or container – to avoid losing small details.
• 🔥 Fire-resistant surface – in case the battery is damaged and can ignite.
• 📸 Smartphone for photography – fix the location of parts before disassembling!

Also, prepare the workplace: it should be well lit, without carpets or flammable materials. If the overbank is bloated or deformed, do not try to disassemble it, this is a sign of a battery failure, and the risk of fire is too high, in such cases, the device must be disposed of according to the rules (at the points of reception of batteries).

⚠️ Warning: If the overbank has been recently used, let it cool for 1-2 hours. Heating lithium-ion cells increases the risk of damage when disassembling them.

External inspection and model identification

Before disassembling, make sure you have a Xiaomi 20,000 mAh, not another model. On the box or sticker on the case, look for the following markings:

• 📦 Model: PLM03ZM, PLM05ZM, PLM06ZM or MDY08-EP (fast-charging versions).
• 🔋 Capacity: 20,000 mAh (actual - about 12,000-13,000 mAh due to conversion losses).
• 🔌 Ports: 2×USB-A (exit, 1×Micro-USB or USB-C (entrance, depending on the version).

Pay attention to the way the cover is attached:

• Older models (PLM03ZM) have a body glued + there are 2 screws under the legs.
• The new ones (PLM05ZM and newer) have only latches, no screws.

If the hull has swelling, cracks or corrosion marks near ports, disassembly can be dangerous.

Step-by-step disassembly of the hull

Now, to the most critical stage, follow the instructions carefully so that you don't break the latches.

1. Take off the stickers (if there are any on the ends) and there may be screws hiding under them.
2. Find the gap between the top and bottom of the case. Start at the corner where there are no ports.
3. Put the mediator in and gently lead along the seam, alternately snapping the mounts. Apply force perpendicular to the body, not sideways!
4. Check the opposite side – sometimes the latches are asymmetrical.

If the case doesn't lend itself, don't use excessive force. You may have missed a screw or a latch. USB-C models often have additional mounts near the port.

Make sure all latches are snapped | Check for hidden screws under stickers | Disconnect the plumes (if any) before removing the board | Photograph the location of the parts-->

After removing the cover, you will see:

• 🔋 Battery unit (usually 2 cells 18650 or flat assembly).
• 📱 Control board with charge/discharge controller.
• 🔌 Ports USB, soldered to board or connected by plumes.

⚠️ Warning: Don't touch battery contacts with metal objects - this can cause short circuit! use plastic or wooden tools.

Internal components analysis

Inside the Xiaomi 20000 mAh, you'll find a typical external battery circuit.

The most common problems that users face are:

• 🔋 Quick discharge – usually worn-out cells or failure are to blame BMS.
• 🔌 Not charging - check the port Micro-USB/USB-C cable.
• 💥 Bloating – requires immediate disposal.

If you've taken out a battery replacement, consider that new cells must be the same model and capacity as the original ones. Using cheap ones can cause fire! Use low-temperature solder and flux to solder them so you don't overheat the board.

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Before soldering the new cells, charge them to 3.7-3.8 V using a laboratory power supply, which will save the BMS from triggering protection on the first turn on.

Frequent Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when disassembling.

• 🔨 Broken latches - use thin mediators and take your time. If the latches break, the body can be glued with cyanoacrylate glue (but this is a temporary solution).
• ⚡ Short circuit – never touch the battery plus and minus at the same time with metal tools.
• 🔥 Overheating when soldering – use a soldering iron with a power of no more than 30 W and work quickly.
• 📉 Incorrect assembly – if the overbank does not work after assembly, check the polarity of the cell connection and the integrity of the plumes.

If the device does not turn on after disassembly, perform an algorithm check:

1. Check the integrity of the wires between the battery and the board.
2. Make sure the BMS board is not in protection mode (sometimes short-term closure of the B- and P- contacts helps).
3. Connect the laboratory power supply to the battery outputs (3.7-4.2 V) and check if the indicators light up.

⚠️ Warning: If the board starts to warm up or smoke when connected to the power supply, turn off the power immediately.

Battery replacement: choice of cells and soldering

If the original cells are worn out, they can be replaced. For Xiaomi 20000 mAh, the following models are suitable:

• 🔋 Samsung INR18650-35E (3500 mAh, 10A) — Original cells in most versions.
• 🔋 LG INR18650 MJ1 (3500 mAh, 10A) — good-fashion.
• 🔋 Panasonic NCR18650B (3400 mAh, 6.8A) — More secure but less powerful.

Replacement process:

1. Seal off old cells without overheating the fee.
2. Seal new ones while observing polarity (+ ce +, − ce −).
3. Isolate contacts with a shrink tube or tape.
4. Check the voltage at the exits. BMS-fees (should be ~3.7 V per cell).

After replacing the battery, be sure to calibrate:

1. Completely discharge the overbank (before disconnection).
2. Charge up to 100% with the original cable.
3. Repeat the cycle 2-3 times.

This will help BMS to correctly determine the capacity of new cells.

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Use only high-quality cells from proven manufacturers (Samsung, LG, Panasonic) cheap analogues may not meet the declared capacity and pose a danger!

Assembly and testing after repair

Collect the verbank in reverse order:

1. Put the battery and the fee in their places.
2. Connect all the plugs and connectors (if they were disconnected).
3. Close the case, making sure the latches are in place.
4. Then, put the slacks on (if they were).

After assembly, perform the test:

• 🔌 Connect to charging and check if the indicator is on.
• 📱 Connect your smartphone – the charge should start.
• 🔋 Check the display of the charge level (click the button on the case).

If something doesn’t work, take the device apart again and check:

• Integrity of soldered joints.
• Correct connection of the plumes.
• No short circuits on the board.

If the power bank is charging but it's not giving off current, the problem may be the safety controller. BMS:

1. Turn off the battery from the board.
2. Press and hold the switch on for 10-15 seconds.
3. Put the battery back on.

FAQ: Frequent questions about the dismantling of Xiaomi 20000 mAh