How to Change an iPhone 8 Battery (Safe DIY Guide)

What You’ll Need

New iPhone 8 battery (with adhesive strips)
Pentalobe screwdriver (for bottom screws)
Phillips #000 screwdriver
Suction cup
Plastic opening picks or spudger
iOpener or heat gun/hair dryer
Tri-point Y000 screwdriver (for battery connector cover)
Tweezers
Isopropyl alcohol (optional, for residue)
Adhesive strips or double-sided tape for new battery

Step-by-Step

Power off and remove screws: Turn off your iPhone. Remove the two pentalobe screws at the bottom edge near the Lightning port.
Heat the display: Apply the iOpener or a heat gun/hair dryer along the edges of the screen for about 2 minutes to soften the adhesive.
Open the display: Place a suction cup near the bottom of the screen (above the Home button) and pull up gently to create a gap. Insert an opening pick into the gap and slide it along the edges to separate the adhesive.
Open the phone like a book: Lift the display from the bottom, but do not pull it all the way—it’s still attached by cables at the top. Tilt it to about 90 degrees and rest it against something.
Remove the display shield: Use the Phillips screwdriver to remove the four screws securing the metal bracket over the display cable connectors. Keep track of screw positions.
Disconnect the display cables: Use a spudger to gently pry up the three cable connectors (for the display, digitizer, and front camera). Now you can completely separate the display assembly.
Remove the battery connector shield: Use the tri-point screwdriver to remove the three screws on the bracket covering the battery connector. Lift the bracket off.
Disconnect the battery: Use a spudger to gently pry the battery connector up from its socket. Do not use metal tools near the battery.
Remove the old battery: Pull the two adhesive strip tabs at the bottom of the battery (gently, one at a time) to release the battery. If a strip breaks, use a spudger to carefully pry the battery up, or use a bit of isopropyl alcohol around the edges to loosen the adhesive. Never puncture the battery.
Install the new battery: Peel the backing off the new adhesive strips and press them into the battery well. Place the new battery in, press down firmly, reconnect the battery connector, and replace the shield. Then reattach the display cables and shield, close the display, press the edges to seal, and replace the bottom screws.

Common Mistakes

Prying the battery with a metal tool: This can puncture the battery and cause a fire. Always use plastic tools.
Pulling the adhesive strips too hard: They can snap off, leaving you with a stubborn battery. Pull slowly and evenly.
Forgetting to disconnect the battery before working on other parts: This can short-circuit the logic board.
Mixing up screws: Screws are different lengths; putting the wrong one in can damage the board. Keep them organized.
Rushing the heating step: Not enough heat makes it hard to open the screen and can crack it.

Tips

Work in a well-lit area and use a magnetic mat to hold screws.
If the screen doesn’t open easily, apply more heat—don’t force it.
When disconnecting cables, use the edge of a spudger, not the tip, to avoid tearing the ribbon.
After replacing the battery, let the phone sit for a few minutes before powering on.
If you’re unsure about the adhesive, use double-sided tape designed for phone batteries.

Troubleshooting

Phone won’t turn on: Check that the battery connector is fully seated and the shield is secure. Also check the display cables.
Screen shows lines or is unresponsive: Likely a loose display cable. Reopen and reseat the connectors.
Screen has a yellow tint: You may have damaged the display during opening; this is common if too much force was used.
Battery drains fast: Calibrate the new battery by using the phone until it dies, then charging to 100% without interruption.
Phone heats up: Ensure the battery is not swollen and that the adhesive is not blocking any sensors.
Home button not working: If you broke the Home button cable, you’ll need to replace the entire button (which requires a screen replacement).

Frequently Asked Questions

Do I need to replace the screen adhesive?

Yes, it’s recommended to replace the adhesive around the display to maintain water resistance. You can buy pre-cut adhesive strips.

How long does the new battery last?

A genuine or high-quality replacement battery should last as long as the original did when new—typically a full day of moderate use.

Can I use a non-Apple battery?

Yes, but quality varies. Look for batteries with good reviews and safety certifications.

Will this void my warranty?

If your iPhone is still under warranty, opening it will void that warranty. This is only recommended for out-of-warranty devices.

What if I break the screen?

You’ll need to replace the screen assembly. It’s a common risk, so be extra careful during the opening step.

Is it safe to use a heat gun?

Yes, but keep it on low heat and keep it moving. Never concentrate heat on one spot for too long.

Sources: Apple Support. Menus and buttons can differ slightly by version. Spotted something out of date? Tell us.