Xiaomi 12 Battery Replacement - Xiaomi Mi 12

Step 1 | Loosen the rear glass adhesive

Do not start repairs with a charged battery — it may catch fire if damaged.

Allow your phone's battery to fully drain before proceeding.
Unplug any cables and shut down your device completely.

Use caution when applying heat, as the display and internal battery can be damaged by excessive heat.

Apply an iOpener to the rear glass for two minutes to loosen the adhesive underneath.
Alternatively, use a hair dryer, heat gun, or hot plate — but avoid overheating your device.

Step 2 | Insert an opening pick

Creating a gap may require significant force due to strong adhesive.

Apply more heat and try again if initial attempt fails.
If rear glass is badly cracked, cover with clear packing tape or use very strong tape instead of suction handle.
As last resort, superglue suction handle to broken rear glass.

Attach suction handle to center of bottom edge as close to edge as possible.

Pull up on suction handle with steady force to create gap between rear glass and frame.
Insert opening pick at charging port location.

Step 3 | Slice the bottom edge adhesive

Avoid inserting the pick deeper than 4mm to prevent damage.

Slide the opening pick to the bottom right corner of the rear glass.
Slice the adhesive with the opening pick and leave it in place.

Step 4 | Insert a second opening pick

Insert another opening pick at the bottom right corner and slide it down to the bottom left corner of the rear glass to cut through the adhesive.

Keep this additional pick in position so the adhesive can't reform.

Step 5 | Slice the left edge adhesive

Apply iOpener for 1-2 minutes or use a hair dryer/heat gun to reheat stiff adhesive.

Insert third opening pick under bottom left rear glass corner.
Slide opening pick along left edge of rear glass to slice adhesive.

Leave opening pick in top left corner to prevent adhesive resealing.

Step 6 | Slice the top edge adhesive

Insert an additional opening pick under the top left corner of the rear glass.
Slide this new pick along the top edge, using it to slice the adhesive.
Leave the pick in place at the top right corner to prevent resealing.

Step 7 | Slice the right edge adhesive

Insert a fifth opening pick under the top right corner of the rear glass.
Slide the pick to the bottom right corner, slicing the remaining adhesive.

Step 8 | Remove the rear glass

Remove the rear glass.
If it's still attached, use an opening pick to slide around the entire perimeter until separated.

Power on your phone and test functions before sealing; power down completely after testing.

Clean the rear glass area with isopropyl alcohol (>90%) and a lint-free cloth.
Secure the rear glass with pre-cut adhesive or double-sided tape during reassembly.

Apply strong, steady pressure to your phone for several minutes after installing the rear glass; a stack of heavy books can help ensure proper adhesion.

Step 9 | Loosen the charging coil assembly

Locate the interconnect cable running underneath the charging coil.

Be cautious not to damage the interconnect cable during removal.

Insert an opening pick under the bottom right corner of the charging coil and slide it toward the charging port
Repeat for the bottom left corner of the charging coil, avoiding damage to the interconnect cable.

Step 10 | Remove the indicator sticker

Remove any protective stickers or markers covering screws.

Pierce the orange water damage indicator sticker on top edge of motherboard cover with a screwdriver or tweezers.
Remove the pierced sticker completely from the screw head.

Step 11 | Unfasten the flash connector cover

Remove the flash connector cover using a Phillips screwdriver.

The four screws have a length of 5.4 mm.
Remove all four screws to access the connector.

Step 12 | Remove the flash connector cover

Remove the flash connector cover using tweezers or your fingers.

Step 13 | Disconnect the flash

Use the flat end of a spudger to pry up the flash press connector and disconnect it.

Step 14 | Unfasten the motherboard cover screws

Use a Phillips screwdriver to remove the following screws:

Five black screws, 5.4 mm long.
Two silver screws, 4.4 mm long.

Step 15 | Pry up the motherboard cover

Locate the plastic clips holding the motherboard cover in place.

Insert an opening pick under the bottom right corner of the motherboard cover.
Pry up on the pick to loosen the first clip.
Slide the pick along the right edge of the motherboard cover.
Twist the pick to release the remaining clips.

Step 16 | Remove the motherboard cover

Remove the motherboard cover.

The charging coil will also lift up.

Step 17 | Disconnect the battery cables

Disconnect both battery cables using the flat end of a spudger. Prying the connectors straight up from their sockets.

Step 18 | Disconnect the interconnect cable

Avoid bending pins by aligning the connector properly.

Use a spudger's flat end to pry up the interconnect cable press connector.
To reattach, carefully align the connector and press down on one side until it clicks.

Repeat on the other side; do not press in the middle.

Step 19 | Reposition the interconnect cable

Do not strain or crease the interconnect cable.

Flip the interconnect cable over the phone's bottom edge.
Use a small piece of tape to hold the cable in place on your work surface, if needed.

Step 20 | Peel up the battery pull-tabs

Do not damage the battery with your tools — risk of chemical leakage and/or fire.

Use blunt nose tweezers or a clean fingernail to carefully peel up the orange "A" pull-tab.

Step 21

Peel up the orange pull-tab labeled "B" using a pair of blunt nose tweezers or a clean fingernail.

Step 22 | Lift the battery

Do not apply direct heat to the battery — risk of fire.

Grip both sides of the pull-tab "A" and pull up to lift the battery out.
If needed, use an iOpener, hair dryer, or heat gun to soften the adhesive under the battery by heating the screen side until it's barely too hot to touch.

Step 23 | Remove the battery

Never reuse a damaged or deformed battery — risk of fire hazard.

Peel off the old battery, taking care not to tear remaining adhesive.
Dispose of the used battery and replace it with a new one.

To install a new battery:

Tweezers or fingers: Remove old adhesive from frame.
High-concentration isopropyl alcohol (≥90%) and lint-free cloth: Clean any remaining adhesive residue.
Temporarily connect replacement battery cables to motherboard, then lay in recess to ensure proper fit and orientation.
If new battery lacks adhesive: Apply Tesa Tape directly to battery recess where old adhesive was.
Lay replacement battery in its recess; press down firmly on entire surface to secure it.