Samsung Galaxy S21 Battery Replacement

Written By: Alex Diaz-Kokaisl

Comments: 11

Difficulty

Moderate

Steps

Time Required

1 - 2 hours

Introduction

Use this guide to remove or replace the battery in your Samsung Galaxy S21.

For your safety, discharge the battery below 25% before disassembling your phone. This reduces the risk of a dangerous thermal event if the battery is accidentally damaged during the repair. If your battery is swollen, take appropriate precautions.

Although it’s not necessary to remove the interconnect cables to replace the battery, we advise doing so. It makes the battery removal and reassembly much easier.

You'll need replacement adhesive in order to complete this repair.

Tools

Parts

Step 1

Completely power off your phone before you begin.
Heat an iOpener and apply it to the back cover's bottom edge for two minutes.
A hair dryer, heat gun, or hot plate may also be used, but be careful not to overheat the phone—the display, internal battery, and plastic back cover are both susceptible to heat damage.

How hot does the back cover have to be to come off? I tried with iOpener many times but have had no luck opening it. The surface temperature goes up to 105-110F (43C).

Imtiaz Chowdhury -

Hi Imtiaz!

We don't have a specific temperature that we recommend, but, if you're still having issues separating the adhesive with the iOpener, I would recommend you switch to a hair dryer or a heat pad. The back cover should be slightly too warm to the touch.

Alex Diaz-Kokaisl -

Step 2

Apply a suction cup to the back of the phone, as close to the center of the bottom edge as possible.
Pull up on the suction cup with strong, steady force to create a gap between the back cover and the frame.
Depending on the age of your phone, this may be difficult. If you're having trouble, apply more heat to the edge and try again.
Insert an opening pick into the gap.
Only insert the pick up to 5 mm, as you may damage internal components if you go further.

Are you pulling the suction cup on an angle or something? How can you pull up on cup with nothing tying down the phone?

PCman999 -

The backing is a polycarbonate material - so yes it's plastic. Also, when pulling up with the suction cup your correct in that it is or should be done on an angle. Plus, the back is plastic so it will only flex upwards as you're applying the pressure. Lastly, because the backing is still tapped inside and your pulling upwards, if necessary with the hand that's pulling up you can gently rest the part of your palm/wrist against the phone which may also help in the separation process but remember you're goal is to only lift it enough so you can slide in the separator pick. I use guitar picks myself since I have them laying around all over the place. Good luck, and don't rush yourself :0)

Miles Long -

Step 3

Slide the pick back and forth along the bottom edge to slice through the adhesive.
Leave the pick in to prevent the adhesive from resealing.

Step 4

Apply a heated iOpener to the back cover's left edge for two minutes.

If you have access to a heating pad you can use this instead and save some cash but make sure to turn it on and let it heat up so you check the temperature first as it needs to be hot enough to melt the glue but not damage the components. Typically, these work great because they're designed not to burn a person.

Miles Long -

Step 5

Apply a suction cup to the back of the phone, as close to the center of the left edge as possible.
Pull up on the suction cup with strong, steady force to create a gap between the back cover and the frame.
Insert an opening pick into the gap.
Only insert the pick up to 5 mm, as you may damage internal components if you go further.

Step 6

Slide an opening pick along the left edge towards the bottom left corner to cut the adhesive.
Don't cut past where the camera shell meets the back cover, as you risk cracking the plastic.
Leave the pick in to prevent the adhesive from resealing.

Step 7

Apply a heated iOpener to the back cover's right edge for two minutes.

Step 8

Apply a suction cup to the back of the phone, as close to the center of the right edge as possible.
Pull up on the suction cup with strong, steady force to create a gap between the back cover and the frame.
Insert an opening pick into the gap.
Only insert the pick up to 3 mm, as you may damage the secondary interconnect cable, which runs parallel to the right edge.

Step 9

Slide an opening pick back and forth along the back cover's right edge to cut the adhesive.
Leave the pick in to prevent the adhesive from resealing.

Step 10

Rotate the right-edge opening pick around the top-right corner of the phone.
Only insert the pick up to 5 mm, as you may damage internal components if you go further.
This procedure can be applied to each corner, except the top-left where the rear-facing camera is located.

Step 11

Slide the top-most opening pick as close to the camera shell as possible.
Repeat for the left-edge pick.

Step 12

Heat an iOpener and apply it to the camera shell for two minutes.

Step 13

Rotate the back cover counterclockwise to create a gap between the camera shell and the frame.
Only insert the pick up to 5 mm to avoid scratching the camera.
Insert an opening pick in the gap.
If this method doesn't work, move to the next step for an alternative method; otherwise, skip the next step.

Step 14

Gently slide the two picks toward the camera shell so they are under the corners of the back cover adjacent to the camera shell.
Move the picks back and forth along the bridge between the back cover and the camera shell until you create a gap between the camera shell and the frame.
Be careful with this method, as you risk cracking the plastic back cover.

Step 15

Slide an opening pick between the camera shell and the frame to cut the adhesive.
There's a significant amount of adhesive securing the frame to the camera shell, so multiple rounds of heating may be needed.

Step 16

There's additional adhesive to the right of the camera that you need to cut through.
There's a plate on the back cover surrounding the phone's flash that the pick can get stuck on:
Angle the pick downward to avoid any damage.

Step 17

Line up the opening pick's tip with your phone's flash
Insert the pick slowly, making sure to avoid the flash's plate.
The plate's resistance can feel similar to adhesive. Angle the pick downward to keep the pick from sliding into the plate.
Slice the adhesive to the right of the camera.

Step 18

Remove the back cover.
If your back cover is still sticking to the frame, slide the pick around the edges of the phone until the back cover completely separates.
During reassembly:
This is a good point to power on your phone and test all functions before sealing it up. Be sure to power your phone back down completely before you continue working.
Remove any adhesive chunks with a pair of tweezers or your fingers. Use some high concentration (over 90%) isopropyl alcohol to wipe away any adhesive residue.
If you're using Samsung custom-cut adhesives, follow this guide.
If you're using double-sided tape, follow this guide.

Step 19

Use a Phillips screwdriver to remove the five 4 mm-long screws securing the motherboard bracket to the frame.
Throughout this repair, keep track of each screw, and make sure it goes back exactly where it came from.

Step 20

Use a pair of tweezers to gently pull up and unclip the motherboard bracket from the frame.
Do not completely remove the bracket yet, as it's still attached to the wireless charging coil.

Step 21

While using tweezers, or your fingers, to hold the motherboard bracket out of the way, use a spudger to pry up the battery press connector.
Take care to pry only under the edge of the connector to prevent damaging the socket itself and surrounding components.
To re-attach press connectors like this one, carefully align and press down on one side until it clicks into place, then repeat on the other side. Do not press down on the middle. If the connector is misaligned, the pins can bend, causing permanent damage.

Step 22

While still holding the motherboard bracket out of the way, use a spudger to pry up and disconnect the wireless charging coil's press connector.

Step 23

The wireless charging coil is secured to the phone with light adhesive.
Use your fingers to gently peel the wireless charging coil away from the phone.
During reassembly, refasten the motherboard bracket screws first to properly align the charging coil into place, then firmly press the rest of the coil down to adhere it.

Step 24

Use a Phillips screwdriver to remove the six 4 mm screws securing the loudspeaker to the frame.

Step 25

Insert the point of a spudger into the notch in the top-left corner of the loudspeaker and pry up to release the clips holding it in place.
Remove the loudspeaker.

Step 26

Use the flat end of a spudger to pry up and disconnect the primary interconnect cable's press connector.

Step 27

Use the flat end of a spudger to pry up and disconnect the secondary interconnect cable's press connector.

Step 28

Use the flat end of a spudger to pry up on the secondary interconnect cable's press connector.
Repeat for the primary interconnect cable's press connector.

Step 29

Use tweezers, or your fingers, to remove the secondary and primary interconnect cables.

Step 30

Use a spudger to pry up and disconnect the display cable's bottom press connector.

Step 31

Use a spudger to pry up and disconnect the display cable's top press connector.

Step 32

Use tweezers, or your fingers, to remove the display cable.

Step 33

Take care not to puncture or bend the battery during the removal procedure—a punctured or bent battery may leak dangerous chemicals or cause a thermal event. In case you're struggling to pull up the battery, apply more isopropyl alcohol and try again.
Apply a few drops of high concentration (over 90%) isopropyl alcohol to the gaps surrounding the battery's perimeter.
Only apply a few drops initially and apply more if necessary; too much isopropyl alcohol might overflow onto the motherboard and daughterboard.

Step 34

Apply a suction cup to the battery, as close to the center of the right edge as possible.
Insert an opening pick into the edge with the widest gap between the frame and the battery.
Rotate the opening pick to insert its long edge into the gap.

Step 35

Pull up on the suction cup with strong, steady force and pry up with the opening pick to separate the battery from the frame.
If you're struggling to pull up the battery with your suction handle, apply a few more drops of isopropyl alcohol.

this does not wqork and I am afraid of breaking the battery or my hand

Saranii muller -

Step 36

Remove the battery, making sure to peel off any remaining adhesive.
Do not reinstall a damaged or deformed battery, as doing so is a potential safety hazard.
Secure the new battery with pre-cut adhesive or double-sided adhesive tape. In order to position it correctly, apply the new adhesive into the device at the places where the old adhesive was located, not directly onto the battery. Press the new battery firmly into place.
During reassembly, temporarily reconnect the battery to the motherboard to help align it correctly. Disconnect the battery after it's seated.
If there's any alcohol remaining, use a lint-free cloth or allow it to dry off before installing a new battery.

Conclusion

Compare your new replacement part to the original part—you may need to transfer remaining components or remove adhesive backings from the new part before installing.

To reassemble your device, follow the above steps in reverse order.

Follow this guide to perform a battery cycle reset, and calibrate your newly-installed battery.

Take your e-waste to an R2 or e-Stewards certified recycler.

Repair didn’t go as planned? Check out our Answers community for troubleshooting help.

Author

Alex Diaz-Kokaisl

Member since: 16/01/22

117875 Reputation

5 comments

Will it void my warranty

BakaDolev -

Yes, unfortunately the warranty will be voided if you "tamper" with any of the components.

Alex Diaz-Kokaisl -

Just a note to the last step regarding iso. Be careful not applying too much iso - it will run down to the display via the hole in the back.

Adam Skou Ohana -

The glue is a pain but I wasn't nearly as careful on the bottom part as the guide suggested and was able to get it off just fine. I also didn't bother to remove the old glue and it holds well enough

Josh Oxborrow -

will my waterproofness go away

Rzgar67 -