How to Replace the Battery on a Samsung Galaxy Z Flip 4

Samsung Galaxy Z Flip 4 Battery Replacement

Foldable phones look complicated, but they’re not as scary as they seem.
In this guide, we’ll show you how to replace the battery on a Samsung Galaxy Z Flip 4, step by step.

If your phone drains fast, shuts down randomly, or won’t hold a charge anymore, a battery replacement can bring it back to life.

Let’s get started.

Tools You’ll Need 🧰

• Polar Tech Magic Self-Heating Pad 

• Polar Tech Phone Repair Toolkit (Isopropyl alcohol ,Metal shim, Plastic pry card, Tweezers, Spudger, Precision screwdriver set)

Step 1: Heat & Remove the Back Cover 

In our case, the back cover was already loose, so we didn’t need to apply heat.

Instead, we used isopropyl alcohol to soften the adhesive.
Once a small gap appeared, we inserted a thin plastic sheet and slowly worked around the edges.

If you feel resistance, just add more alcohol and keep going gently.
No rushing—your phone will thank you.

After most of the adhesive was separated, we cut away the visible glue and disconnected the BTB connector.
Now the back cover can be removed safely.

Step 2: Remove the Old Batteries 

The Galaxy Z Flip 4 uses two batteries: an upper and a lower one.

First, we took out the screws and removed the metal plate.

Once that’s done, you can disconnect the connectors.
A magnetic mat is super helpful here—tiny screws love to escape.

Next, we applied a bit of alcohol to soften the battery adhesive.
Using a pry tool, the battery came out easily.

We repeated the same process for the lower section:
remove screws, disconnect components, soften the adhesive, and lift the battery out.

Step 3: Install the New Batteries 

Before installing the new batteries, we cleaned all the old adhesive from the frame.

This step is important.
Old glue can stop the back cover from sitting properly.

Once everything was clean, we installed the new upper and lower battery and reconnected all the BTB connectors.

We also temporarily reinstalled the upper back cover to protect the camera from dust.

Then, we moved to the lower section and installed the new lower battery, following the same steps.

Step 4: Reassemble, Seal & Test 

After installing both batteries, we reassembled all the components.

Next, we cleaned the adhesive from the back cover.
We applied fresh double-sided tape and added a small amount of B7000 glue for extra sealing.

Once everything was aligned, we sealed the phone and powered it on.

The screen lit up perfectly.
Everything worked as expected.

Repair complete. 🎉

Final Thoughts

Replacing the battery on a foldable phone might sound intimidating, but with the right tools and a bit of patience, it’s totally doable.

📩 Need help with your device?

If you have any questions or need further details,contact us or leave a comment below. We’re always happy to help.

👋 See you in the next one! 

📷 Bonus: Want to See the Process?

Watch our full teardown and battery replacement video here:
👉 [YouTube Link]

Where can I buy replacement screen and tools?

[EB-BF723ABY & EB-BF724ABY] Samsung Galaxy Z Flip 4 (F721) Replacement Battery : https://www.polartech.com.au/collections/samsung-galaxy-z-fold-spare-part/products/eb-bf723aby-eb-bf724aby-samsung-galaxy-z-flip-4-f721-replacement-battery

[PT-H01] Magic Self-Heating Pad: https://www.polartech.com.au/products/pt-h01-magic-self-heating-pad

[NS05] [5 in 1 Set]Ultra-Thin Stainless ScreenDisassemble Blade Opening Tool: https://www.polartech.com.au/products/jns05-5-in-1-set-ultra-thin-stainless-screen-disassemble-blade-opening-tool

[PT-T13] [27 in 1] Polar Tech Phone Repair ToolkitScrewdriver Basic Kit Set For Smart Phone &Tabet: https://www.polartech.com.au/products/pt-t13-27-in-1-polar-tech-phone-repair-toolkit-screwdriver-basic-kit-set-for-smart-phone-tabet

[TE-03] Opening Tool Soft Blade Pry Bar OpenRepair Tool Kit: https://www.polartech.com.au/products/te-03-opening-tool-soft-blade-pry-bar-open-repair-tool-kit

[CXD-01] [15cm x20cm] Magnetic Project MatScrew Magnet Memory Phone Repair Working Pad: https://www.polartech.com.au/products/cxd-01-15cm-x-20cm-magnetic-project-mat-screw-magnet-memory-phone-repair-working-pad

[CHF1] [With Ruler] Mobile Phone Repair Plastic Separating Card Disassemble Pry Opening Tools: https://www.polartech.com.au/products/chf1-with-ruler-mobile-phone-repair-plastic-separating-card-disassemble-pry-opening-tools