Xiaomi Redmi Note 9 Battery Replacement

Locate the SIM eject hole on the left edge of the phone.

• Insert a SIM eject tool, SIM eject bit, or a straightened paper clip into the hole.

• Press directly and firmly into the hole to avoid damaging the SIM tray.

• Remove the SIM card tray.

When removing the back cover, be aware that it is held in place with plastic clips and adhesive.

• Prepare an iOpener and apply it to the back cover for at least two minutes to loosen the adhesive underneath.
• Alternatively, use a hair dryer, heat gun, or hot plate, but be cautious not to overheat the phone and avoid damaging the display or internal battery.

Secure a suction handle to the screen's bottom edge, as close to the edge as possible.

• If the screen is cracked, attempt to attach the suction handle with strong tape or superglue it in place and let it cure before proceeding.
• Lift the phone assembly using the suction handle, creating a small gap between the assembly and back cover.

Apply additional heat to soften the adhesive if necessary, following iOpener instructions to avoid overheating.

• Insert an opening pick at a steep angle into the created gap, using force if needed.
• Slide the pick to the bottom right corner, slicing the adhesive and releasing the plastic clips holding the back cover in place.

• Insert a second opening pick at the bottom edge, angled steeply.
• Slide it towards the bottom left corner to release clips and cut adhesive.

Leave opening picks in place to prevent resealing of adhesive.

Check if adhesive is too hard to cut; if so, use iOpener to reheat.

• Insert new opening pick at bottom left corner at steep angle.
• Slide pick along left edge to release clips and slice adhesive.
• Leave one opening pick in top left corner to prevent resealing of adhesive.

Do not attempt to separate the phone components fully yet.

• Insert a fourth opening pick at the bottom right corner of your phone in a steep angle.
• Slide the pick along the right edge to release plastic clips and slice adhesive.
• Leave the pick in the top right corner to prevent resealing.

Flip your Redmi Note 9 over.

Avoid straining the fingerprint flex cable during this procedure.

• Fold the back cover to the right side of the phone assembly, like opening a book from the back.
• Slide the back cover underneath the phone assembly, ensuring it overlaps about one third and does not strain the fingerprint flex cable.

Remove the motherboard cover by unscrewing the eleven 3.9 mm screws using a Phillips screwdriver.

Insert the opening pick under the bottom left edge of the motherboard cover.

• Pry up the motherboard cover carefully.

Remove the motherboard cover.

• Disconnect the fingerprint cable by prying the connector straight up with a spudger.
• Separate the phone assembly from the back cover.

Disconnect the battery connector by prying it straight up with a spudger.

Use a spudger to pry the display cable connector straight up out of its socket.

Use a spudger to pry the interconnect cable straight up from its socket.

Do not fold the cable sharply to avoid damage.

• Fold the display and interconnect flex cable towards the charging port.
• This will give you access to both battery pull tabs and the battery.

You can use a small piece of tape to temporarily secure cables on your workspace, avoiding accidental damage during removal.

Use tweezers or your finger to gently bend the battery cable to the left.

Risk of damage to the cable or surrounding components if bent too forcefully.

Avoid using sharp tools on the battery to prevent damage and potential fires.

• Peel down both battery adhesive pull-tabs with blunt nose tweezers or a clean fingernail.

Hold the phone firmly by its sides.

• Pull-tab at a low angle using blunt tweezers or fingers.
• Maintain tension on the strip but do not force it.
• Give it plenty of time to stretch and unstick from under the battery.

Do not press down on the battery.

• Pull evenly on the whole strip, avoiding wrinkles.
• If the strip breaks off, try to retrieve it with your fingers or tweezers and continue pulling.
• If it cannot be retrieved, proceed to the next step.

Repeat the previous pull-tab removal procedure on the second pull-tab.

• Keep the strip flat and unwrinkled while pulling at a low angle, just like before.
• If adhesive breaks off underneath the battery, apply high concentration (over 90%) isopropyl alcohol under the edge of the battery where it's stuck.

Wait about one minute for the alcohol solution to weaken the adhesive.

• Use a spudger's flat end to gently lift the battery, rather than trying to lever it out.
• If necessary, add more drops of alcohol to further loosen the adhesive.

Never deform or puncture the battery with your pry tool — this can cause damage.

Do not reinstall a damaged or deformed battery as this poses a potential safety hazard.

• Remove the battery.
• If any alcohol solution remains, wipe it off with a cloth or let it air dry before installing your new battery.

Temporarily reconnect the battery to the motherboard during reassembly for alignment purposes, then disconnect it once seated.