Replacing the battery

The battery life is too low. Your iPhone keeps crashing or won’t charge.

  • iPhone 8
  • 34 Steps
  • Difficult
  • 60 min.
Go to the guide

Introduction

In this guide, we show you how to replace your iPhone 8's defective battery on your own. This repair can help if your iPhone 8 crashes during heavy use because the voltage temporarily drops, you can no longer charge it or turn it on, or the battery life is very low.
Back up all your data before the repair, and touch something like a radiator to get rid of any static charges.

Required tools

  • Hard Plastic Pick

    Hard Plastic Pick

    You need a flat but stable tool such as a pick to pry out parts that are glued in place.

    €1.00 at the iDoc store
  • Heat gun

    Heat gun

    You can use a heat gun to heat parts that are glued on so they’re easier to remove. In most cases, you can also use a hairdryer.

    from €14.99 on Amazon
  • For storing screws

    For storing screws

    We recommend storing your screws so you don’t mix up the various screws and small parts.

    €10.00 at the iDoc store
  • Phillips screwdriver with centering pin

    Phillips screwdriver with centering pin

    Phillips screwdriver with practical centering pin for logic board screws.

    €6.00 at the iDoc store
  • Plastic prying tool

    Plastic prying tool

    You need a flat plastic prying tool to disconnect the various plugs and connectors.

    €2.00 at the iDoc store
  • Suction cup

    Suction cup

    A suction cup is perfect for lifting smooth surfaces such as displays or rear glass panels.

    €3.00 at the iDoc store
  • Tweezers

    Tweezers

    We recommend using tweezers to remove screws and various small parts from your device.

    €16.00 at the iDoc store
  • Pentalobe PL1 screwdriver

    Pentalobe PL1 screwdriver

    You need the right screwdriver for removing pentalobe PL1 screws.

    €10.00 at the iDoc store
  • Phillips PH00 screwdriver

    Phillips PH00 screwdriver

    You need the right screwdriver for removing PH00 screws.

    €7.00 at the iDoc store
  • Y-type Y000 screwdriver

    Y-type Y000 screwdriver

    You need the right screwdriver for removing Y-type screws.

    €0.00 at the iDoc store

Required replacement part

  • iPhone 8 Battery including Adhesive Strips

    iPhone 8 Battery including Adhesive Strips

    This new battery can help if your iPhone 8 crashes during heavy use because the voltage temporarily drops, your phone switches off when it gets cold, you can no longer charge it or turn it on, or the battery life is very low. Once you’ve installed your new battery, you can talk, listen to music, watch videos or do whatever you want on your phone for much longer.

    €29.00 at the iDoc store
View product(s) at the iDoc store

Replacement parts and tools for this repair

With our tools and the right replacement part, your repair will be a success.

iPhone 8 Battery including Adhesive Strips

This new battery can help if your iPhone 8 crashes during heavy use because the voltage temporarily drops, your phone switches...

Y-Type Toolkit

No matter what the problem is, our Y-Type tool kit can help you fix it. This repair kit includes an opening tool; Wiha PicoFinish Phillips, Y-type...

together for €63.00

Getting started

If you get stuck or have questions, you can post a comment for each step. We’d be happy to help.

34 steps
  1. Switching off your device

    iPhone 8 - Switching off your device 01
    iPhone 8 - Switching off your device 02
    1. Turn your iPhone off completely to avoid damaging it during the repair. Press the Sleep/Wake button for about three seconds until the slider labeled “power off” appears.
    2. Swipe it from left to right. Now your iPhone will shut down completely, which can take about ten seconds.
    Comments
  2. Removing the enclosure screws

    iPhone 8 - Removing the enclosure screws 01
    • 2 × 3.4mm Pentalobe

    You need a pentalobe screwdriver (PL1) to open the iPhone 7.

    1. Remove the two pentalobe screws at the bottom of the enclosure. They’re to the right and left of the Lightning connector. Put the screws in the same section of your magnetic pad.
    Comments
  3. Lifting the display

    iPhone 8 - Lifting the display 01
    iPhone 8 - Lifting the display 02
    iPhone 8 - Lifting the display 03
    iPhone 8 - Lifting the display 04
    1. Put your iPhone 8 on a soft, clean surface to avoid scratching the back.
    2. To lift the front panel, you need a suction cup, a hard plastic pick and a heat gun. If the screen is severely cracked, cover all of it with packing tape before you continue.
    3. The screen is glued to the frame. Use a heat gun to heat the outer edges of the display to about 60°C (140°F).
    4. Place the suction cup over the Home button (if possible) or next to it. While lifting the screen with the suction cup, insert the hard plastic pick between the aluminum frame and the display frame and press down the aluminum frame. Because the display’s glued on, you have to slide the pick all around the iPhone between the aluminum frame and the display frame. Don’t stick the pick in too far on the side where the Sleep/Wake button is because that could damage the flexible flat display cables.
    5. Now use the pick to push the display so the tabs come out of the aluminum frame. Then you can fold the display over to the side.
    6. Set the display on the aluminum frame so you don’t stretch the flexible flat cables too much.

    If necessary, heat the outer edges of the display a few times. Don’t forget that the flexible flat cables for the display are on the side with the Sleep/Wake button. The display is also hooked onto the edge of the earpiece.

    Comments
  4. Disconnecting the battery contact

    iPhone 8 - Disconnecting the battery contact 01
    iPhone 8 - Disconnecting the battery contact 02
    iPhone 8 - Disconnecting the battery contact 03
    • 2 × 2.6 mm Phillips
    • 2 × 1.0 mm Phillips

    Before starting the repair, disconnect the battery contact to prevent short circuits and avoid accidentally turning on your device during the repair.

    1. Use a phillips screwdriver (Ph00) to remove the four phillips screws. Then take off the cover. Put all the parts in the same section of your magnetic pad.
    2. Now carefully lift off the battery contact by inserting a plastic spudger slightly below the connector.
    Comments
  5. Disconnecting the display connectors

    iPhone 8 - Disconnecting the display connectors 01
    iPhone 8 - Disconnecting the display connectors 02
    iPhone 8 - Disconnecting the display connectors 03
    • Connector

    Use the spudger to disconnect the connectors for the display and Home button.

    Comments
  6. Disconnecting the FaceTime connector

    iPhone 8 - Disconnecting the FaceTime connector 01
    iPhone 8 - Disconnecting the FaceTime connector 02
    iPhone 8 - Disconnecting the FaceTime connector 03
    • 3 × 1.0 mm Phillips
    1. Use a Phillips screwdriver (PH00) to remove the three Phillips screws. Then take off the cover. Put all the parts in the same section of your magnetic pad.
    2. Using a spudger, carefully disconnect the FaceTime connector from the PCB.
    3. Now you can take off the display all the way.
    Comments
  7. Removing the iSight camera

    iPhone 8 - Removing the iSight camera  01
    iPhone 8 - Removing the iSight camera  02
    iPhone 8 - Removing the iSight camera  03
    iPhone 8 - Removing the iSight camera  04
    iPhone 8 - Removing the iSight camera  05
    • 1 × 2.9 mm Phillips
    • 1 × 3.0 mm Standoff
    • Connector
    1. Remove the screws which fasten the bracket plate for the iSight camera and remove the bracket plate.
    2. Disconnect the camera by carefully prying off its connector using a spudger.
    3. There are special screwdrivers for removing the internal thread screw, but you can also use a regular, thin slotted screwdriver.

    4. Remove the camera.
    Comments
  8. Disconnecting the standby/volume connector

    iPhone 8 - Disconnecting the standby/volume connector 01
    iPhone 8 - Disconnecting the standby/volume connector 02
    iPhone 8 - Disconnecting the standby/volume connector 03
    iPhone 8 - Disconnecting the standby/volume connector 04
    • 1 × 1.1 mm Phillips
    • 1 × 2.7 mm Phillips
    1. First remove the screws of the bracket plate. Place all screws in the same box on the magnetic mat.
    2. Remove the bracket plate.
    3. Disconnect the connector from the logic board.
    Comments
  9. Removing the plastic bracket

    iPhone 8 - Removing the plastic bracket 01
    iPhone 8 - Removing the plastic bracket 02
    iPhone 8 - Removing the plastic bracket 03
    iPhone 8 - Removing the plastic bracket 04
    iPhone 8 - Removing the plastic bracket 05
    • 2 × 1.2 mm Philliips
    • 2 × 1.0 mm Philliips
    • 1 × 2.5 mm Phillips
    • 1 × 1.4 mm Phillips
    1. First remove the screws from the plastic bracket. Put the screws in the same box on your magnetic pad.
    2. One of the screws goes into the back cover sideways.

    3. Then remove the bracket.
    4. There are more screws under the bracket, which hold a connection piece in place. Remove these screws.
    5. Now remove the connection piece.
    Comments
  10. Removing the Wi-Fi antenna

    iPhone 8 - Removing the Wi-Fi antenna  01
    iPhone 8 - Removing the Wi-Fi antenna  02
    iPhone 8 - Removing the Wi-Fi antenna  03
    iPhone 8 - Removing the Wi-Fi antenna  04
    iPhone 8 - Removing the Wi-Fi antenna  05
    • 1 × 1.3 mm Phillips
    • 1 × 1.2 mm Phillips
    • Connector
    1. First remove the Phillips screws fastening the antenna.
    2. Then disconnect the connector from the board.
    3. The antenna is lightly glued in place. Use a little hot air to detach the antenna or carefully disconnect it by inserting a spatula under the cable.
    4. Then take out the antenna.
    Comments
  11. Removing the SIM card tray

    iPhone 8 - Removing the SIM card tray  01
    iPhone 8 - Removing the SIM card tray  02
    1. You can use the SIM tool or a paperclip to remove the SIM card tray. Press the SIM tool into the small hole in the SIM card tray to remove it.
    Comments
  12. Disconnecting the logic board connectors

    iPhone 8 - Disconnecting the logic board connectors 01
    iPhone 8 - Disconnecting the logic board connectors 02
    iPhone 8 - Disconnecting the logic board connectors 03
    iPhone 8 - Disconnecting the logic board connectors 04
    • Connector
    1. Use a spudger to carefully disconnect the three connectors on the battery side of the logic board.
    Comments
  13. Removing the logic board

    iPhone 8 - Removing the logic board  01
    iPhone 8 - Removing the logic board  02
    iPhone 8 - Removing the logic board  03
    iPhone 8 - Removing the logic board  04
    iPhone 8 - Removing the logic board  05
    iPhone 8 - Removing the logic board  06
    • 1 × 2.4 mm Standoff
    • 1 × 2.1 mm Standoff
    • 1 × 1.6 mm Phillips
    1. Unscrew all screws that hold the logic board in place. You can unscrew the standoff screws using a special screwdriver or a regular, thin slotted screwdriver.
    2. The Phillips screw is covered by a sticker, see photo.

    3. Now you can carefully remove the logic board by hand. Next to the two holes for the iSight camera, there is a plastic holder for a screw.. This plastic holder is placed on top of the logic board.
    Comments
  14. Removing the speaker

    iPhone 8 - Removing the speaker  01
    iPhone 8 - Removing the speaker  02
    iPhone 8 - Removing the speaker  03
    iPhone 8 - Removing the speaker  04
    iPhone 8 - Removing the speaker  05
    iPhone 8 - Removing the speaker  06
    • 1 × 1.2 mm Y-type
    • 1 × 2.9 mm Phillips
    • 1 × 2.5 mm Phillips
    • 1 × 1.4 mm Phillips
    • 1 × 2.1 mm Phillips
    1. First remove the bracket plate over the connector of the flex cable leading to the speaker.
    2. Now disconnect the flex cable and lift out the flex cable a bit.
    3. Then remove the speaker's screws.
    4. You can now remove the speaker with the flex cable.
    Comments
  15. Removing the Taptic Engine

    iPhone 8 - Removing the Taptic Engine  01
    iPhone 8 - Removing the Taptic Engine  02
    iPhone 8 - Removing the Taptic Engine  03
    iPhone 8 - Removing the Taptic Engine  04
    iPhone 8 - Removing the Taptic Engine  05
    iPhone 8 - Removing the Taptic Engine  06
    iPhone 8 - Removing the Taptic Engine  07
    • 1 × 2.0 mm Standoff
    • 1 × 2.0 mm Phillips
    1. First disconnect and remove the small flex cable over the connector of the Taptic Engine.
    2. Remove the screws fastening the Taptic Engine.
    3. Use a spudger to disconnect the Taptic Engine’s connector.
    4. Now remove the Taptic Engine.
    Comments
  16. Removing the battery

    iPhone 8 - Removing the battery 01
    iPhone 8 - Removing the battery 02
    iPhone 8 - Removing the battery 03
    iPhone 8 - Removing the battery 04
    iPhone 8 - Removing the battery 05

    The battery is glued to the case with four adhesive strips. The adhesive strips have tabs to pull them out. The tabs are glued to the top and bottom edges of the battery.

    1. Use tweezers or a spatula to peel off the black tabs. Underneath are the white adhesive strips.
    2. Now pull out the adhesive strips very slowly. Keep the strips as flat as possible at the level of the iPhone.
    3. Firmly hold the battery and iPhone while pulling out the last adhesive strip to prevent the battery from falling out of the device.

      When removing the upper adhesive strips, make sure not to damage the standby/volume cable contact.

      If one of the adhesive strips tears, you have to pry out the battery carefully using a wide Spudger. Try to bend the battery as little as possible.

    4. Once all the adhesive strips are off, you can remove the battery.
    Comments
  17. Preparing the battery

    iPhone 8 - Preparing the battery 01
    iPhone 8 - Preparing the battery 02
    iPhone 8 - Preparing the battery 03
    iPhone 8 - Preparing the battery 04
    iPhone 8 - Preparing the battery 05
    iPhone 8 - Preparing the battery 06
    iPhone 8 - Preparing the battery 07
    iPhone 8 - Preparing the battery 08
    iPhone 8 - Preparing the battery 09
    iPhone 8 - Preparing the battery 010

    To correctly position the battery, you can reinstall all parts except for the logic board. You can place the logic board in the back cover without screwing it.

    Place the adhesive strips with protective films attached in the device to make sure that they point in the right direction.
    1. Remove the large blue protective film and stick the adhesive strips to the bottom of the battery. Make sure they are straight.
    2. Turn the battery over and remove the small blue and pink protective films on the tabs.
    3. Fold the tabs around and stick them to the top of the battery.
    4. Remove the large pink protective film from the adhesive strips.

    When attaching the adhesive strips, leave enough space on both sides to fold over the tabs.

    Comments
  18. Inserting the battery

    iPhone 8 - Inserting the battery 01
    iPhone 8 - Inserting the battery 02
    iPhone 8 - Inserting the battery 03
    1. Put the battery back in the case. Look at the battery connector to see if the battery is aligned correctly.
    2. Leave some space between the frame and other parts on all sides of the battery

    Remove the logic board again, if you placed it in the case to position the battery.

    Comments
  19. Installing the Taptic Engine

    iPhone 8 - Installing the Taptic Engine  01
    iPhone 8 - Installing the Taptic Engine  02
    iPhone 8 - Installing the Taptic Engine  03
    iPhone 8 - Installing the Taptic Engine  04
    iPhone 8 - Installing the Taptic Engine  05
    iPhone 8 - Installing the Taptic Engine  06
    iPhone 8 - Installing the Taptic Engine  07
    • 1 × 2.0 mm Standoff
    • 1 × 2.0 mm Phillips
    1. Put the Taptic Engine back between the battery and the Lightning connector. Make sure the screw holes of the Taptic Engine sit correctly.
    2. Connect the Taptic Engine’s connector.
    3. Fasten the Taptic Engine with the screws.
    4. Insert the mini flex cable and connect its connector.
    Comments
  20. Inserting the speaker

    iPhone 8 - Inserting the speaker  01
    iPhone 8 - Inserting the speaker  02
    iPhone 8 - Inserting the speaker  03
    iPhone 8 - Inserting the speaker  04
    iPhone 8 - Inserting the speaker  05
    • 1 × 2.1 mm Phillips
    • 1 × 1.4 mm Phillips
    • 1 × 1.2 mm Y-type
    • 1 × 2.9 mm Phillips
    • 1 × 2.5 mm Phillips
    1. Place the speaker back in its original position and press it towards the lower edge of the iPhone.
    2. Make sure to correctly position the flex cable between the battery and the speaker.
    3. Now you can fasten the speaker using the screws.
    4. Press in the connector of the flex cable.
    5. Reinsert the bracket plate over the flex cable and fasten it using the screws.
    Comments
  21. Inserting the logic board

    iPhone 8 - Inserting the logic board  01
    iPhone 8 - Inserting the logic board  02
    iPhone 8 - Inserting the logic board  03
    iPhone 8 - Inserting the logic board  04
    • 1 × 2.4 mm Standoff
    • 1 × 2.1 mm Standoff
    • 1 × 1.6 mm Phillips
    1. Reinsert the logic board in its original position. The camera holder should be on top of the logic board. (Over the screw hole on the top right in the image.)
    2. Fasten the logic board using the screws.
    Comments
  22. Connecting the connectors on the logic board

    iPhone 8 - Connecting the connectors on the logic board 01
    iPhone 8 - Connecting the connectors on the logic board 02
    • Connector

    1. Connect the three connectors on the battery side of the logic board. First position the connectors over their sockets and then carefully press them in using a finger.

    Comments
  23. Inserting the SIM card tray

    iPhone 8 - Inserting the SIM card tray  01
    iPhone 8 - Inserting the SIM card tray  02
    1. Now insert the SIM card tray into it slot.

    If you’re having trouble sliding it in, check the position of the logic board.

    Comments
  24. Installing the Wi-Fi antenna

    iPhone 8 - Installing the Wi-Fi antenna  01
    iPhone 8 - Installing the Wi-Fi antenna  02
    iPhone 8 - Installing the Wi-Fi antenna  03
    • 1 × 1.3 mm Phillips
    • 1 × 1.2 mm Phillips
    • Connector
    1. Put the Wi-Fi antenna back where it was originally.
    2. Now screw in its bracket plate.
    3. Then gently press it on so the glue will stick.
    4. Now connect the connector.
    Comments
  25. Installing the plastic bracket

    iPhone 8 - Installing the plastic bracket 01
    iPhone 8 - Installing the plastic bracket 02
    iPhone 8 - Installing the plastic bracket 03
    iPhone 8 - Installing the plastic bracket 04
    iPhone 8 - Installing the plastic bracket 05
    • 1 × 2.5 mm Phillips
    • 1 × 1.4 mm Phillips
    • 2 × 1.2 mm Phillips
    • 2 × 1.0 mm Phillips
    1. Put the connection piece back into its position and fasten it with the Phillips screws.
    2. Now you can reinstall the plastic bracket and fasten it with the screws.
    Comments
  26. Connecting the standby/volume cable

    iPhone 8 - Connecting the standby/volume cable 01
    iPhone 8 - Connecting the standby/volume cable 02
    iPhone 8 - Connecting the standby/volume cable 03
    iPhone 8 - Connecting the standby/volume cable 04
    • 1 × 1.1 mm Phillips
    • 1 × 2.7 mm Phillips
    1. Connect the standby/volume control cable again.
    2. Put the bracket plate back on the connector and fasten it with the screws.
    Comments
  27. Installing the iSight camera

    iPhone 8 - Installing the iSight camera  01
    iPhone 8 - Installing the iSight camera  02
    iPhone 8 - Installing the iSight camera  03
    iPhone 8 - Installing the iSight camera  04
    iPhone 8 - Installing the iSight camera  05
    • Connector
    • 1 × 2.9 mm Phillips
    • 1 × 3.0 mm Standoff
    1. Reinsert the camera into its holder and press into place.
    2. Connect the camera's connector.
    3. Place the bracket plate over the camera and screw it in.
    Comments
  28. Frame sticker

    iPhone 8 - Frame sticker 01
    iPhone 8 - Frame sticker 02
    iPhone 8 - Frame sticker 03
    iPhone 8 - Frame sticker 04
    iPhone 8 - Frame sticker 05
    1. To make sure that the new frame sticker will really stick, remove all residue of the old glue and dirt.
    2. Remove the first backing film.
    3. Position it carefully on one side and press it on gently.
    4. Remove the second piece of film.

    Please note the correct orientation of the frame sticker. The corners of the sticker differ and will help you.Even if you use a new frame sticker, your iPhones' water resistance may not be 100% what it was before!

    Comments
  29. Connecting the FaceTime contact

    iPhone 8 - Connecting the FaceTime contact 01
    iPhone 8 - Connecting the FaceTime contact 02
    iPhone 8 - Connecting the FaceTime contact 03
    iPhone 8 - Connecting the FaceTime contact 04
    • 3 × 1,0 mm Phillips-Schraube
    1. Hold the display upright on the frame and connect the FaceTime contact to the logic board.
    2. Set the display on the side of the frame.
    3. Put the FaceTime contact’s cover back in the iPhone and secure it with the three Phillips screws.
    Comments
  30. Connecting the display

    iPhone 8 - Connecting the display 01
    iPhone 8 - Connecting the display 02
    iPhone 8 - Connecting the display 03
    • Connector
    1. Connect the two connectors from the Home button and display to the logic board.
    Comments
  31. Connecting the battery contact

    iPhone 8 - Connecting the battery contact 01
    iPhone 8 - Connecting the battery contact 02
    iPhone 8 - Connecting the battery contact 03
    iPhone 8 - Connecting the battery contact 04
    • 2 × 2.6 mm Phillips
    • 2 × 1,0 mm Phillips-Schraube
    1. Reconnect the battery by connecting the battery contact.
    2. Put the cover back in the iPhone and secure it with the four screws.
    Comments
  32. Attaching the display

    iPhone 8 - Attaching the display 01
    iPhone 8 - Attaching the display 02
    iPhone 8 - Attaching the display 03
    1. Put the display on the side of the frame and lower it onto the iPhone.
    2. Then press the entire display into the frame.
    Comments
  33. Fastening the enclosure screws

    iPhone 8 - Fastening the enclosure screws  01
    • 2 × 3.4 mm Pentalobe
    1. Screw the two pentalobe screws to the left and right of the Lightning connector into the enclosure.
    Comments
  34. Setting the time

    iPhone 8 - Setting the time  01

    When the battery is removed from the device, the iPhone loses the time and sets itself to 1:00 a.m. on 1/1/1970. You could have trouble connecting to the cellular network if the time isn’t set.

    After a repair, complete the following steps:

    1. Synchronize your iPhone with iTunes or connect to a WLAN network and wait until the time is set.
      The time won’t be set automatically unless you enable this feature in the settings.
      Settings > General > Date & Time > Set Automatically
    2. Remove the SIM tray with the SIM card and reinsert it.
    3. Activate airplane mode on the device and then deactivate airplane mode.
      Settings > Airplane Mode
    Comments

You did it!

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