Samsung Galaxy S6 Edge Battery Replacement Fail
I was recently given 2 old phones, a Huawei P20 Pro (remember those?) and a Samsung Galaxy S6 Edge. The Huawei worked fine, it just wasn't used so I wiped it and traded it in. £55 gained. The Samsung kept boot-looping. I suspected a battery fault; how hard could it be to remove the back cover and just replace it? I was about to find out.
To replace the battery on most modern phones you have to remove the back cover and mess about with adhesive. It takes about 45 minutes if you're doing it for the first time; you also run the risk of cracking the back glass. On my 25 year old Nokia 3310, it's a 30 second job. The clever money checks an iFixit guide before starting work I opted not to as it should have been a simple job and I've fixed enough phones in times past.
The phone was set on a heat mat at 80 degrees Celsius. Prior, I had put tape over the back cover as it was cracked. I couldn't get a suction cup to stick so I resorted to metal tools. If your cover isn't damaged, you don't need the tape and the cup will likely stick fine. Removing the back was easier than expected; all it took was 3 minutes to heat up and some gentle prying. Someone had worked on it before.
I lifted the NFC coil and removed the screws holding the 2 halves of the phone together. At that point I realised a screen removal was required to get at the battery. I had no choice but to press on as the phone wasn't usable. 15 minutes of gentle prying ensued. I used playing cards, plastic tools, heat, alcohol and as little force as possible. One of the playing cards went between the screen and the glass. I assumed the screen was broken at that point but I didn't have a way of knowing.
The screen came off the phone with a start. The whole time I'd thought I was missing something - a screw, a cable, etc. but it was just that well adhered. Getting the battery out wasn't too tough all things considered. I used a playing card (my favourite tool it seems) and some 99.9% pure alcohol. I used the card as a ramp to get the alcohol under the battery as the adhesive was strong... I wasn't surprised.
The next few steps were at least simple: unplug the ribbon cables, remove the front camera, unplug the antennas and lift the motherboard out of the phone. I took some solace in knowing I at least had a motherboard I cold sell, the more valuable 64GB version at that! Just to rub salt in the wound, the new battery didn't fit. I bought an S6 Edge battery but in no position was the cable long enough. Since I still didn't know if the phone worked I decided to put the old battery back in and test the screen.
Sure enough the screen was broken. A replacement screen costs the same as the phone so what point would there have been in buying one? It was aggravating to have spent money on a back cover and a new battery as well invest so much time only to have it not work out but, as always, I learnt something - check iFixit prior to starting any work. You shouldn't have to but hey, that's the modern world. Also, a genuine used battery is a better choice than a generic new one. It wasn't possible to back the data up prior (nothing important was on there anyway) but you'd be wise to back your data up before starting a repair if you have anything important you don't want to lose.
Now I had a dilemma. Should I carry on in spite of the broken screen just to show the whole process for the video or should I stop there? If I hadn't been recording, I'd have stopped. In the end, I thought I'd see it through. Ironically there wasn't much left to do but I still managed to do it badly!
With replacement screens, you usually get an adhesive template. The idea is you lay it in the phone and peel off the backing layer. Then the screen can go in the phone and everyone's happy. I didn't have the template so I opted to use T-7000, my favourite compound. For some unknown reason, I chose to put the adhesive on the screen and not in the frame. I don't know what I was thinking... My blunder was compounded by orders of magnitude as the wretched screen didn't fit back in the phone; it wouldn't line up. At that point I had wasted over an hour, I was tired and fed up. I managed to get the screen on but only with the help of excessive force...
In the above, there's another lesson. Make sure everything lines up and fits as expected. Do a dry fit first. If it doesn't fit and the adhesive is already down, you're scuppered!
Ironically, despite being absolutely caked in T-7000, the screen cleaned up very nicely. The body of the phone looked great and the buttons still clicked! Re-installing everything else was simple. I plugged the cables in, inserted the SIM tray and put the screws back.
What about the back cover? Part of the original fix. Once the old adhesive was cleaned out of the channel, (with the help of a flat-head screwdriver), more T-7000 was used. More went on than I'd have liked but it was a hot day thus the liquid was thinner and flowed out of the tube more quickly. Once lined up the back cover went right on. I used clamps to hold it down securely as the glue dried. When it was set I removed the adhesive by rubbing up and down over it.
So, I'd spent 1hr 45 breaking a phone further. Modern Samsung smartphones are simpler to repair, as long as you aren't counting their foldables, but the fact they ever put out such a badly designed and hard to fix device is hard to forgive. I currently own an S23 and I'm happy with it but I won't be buying a Samsung to replace it.
If you're taking on a similar repair then hopefully you can learn from my mistakes: make sure the screen lines up before applying the adhesive, make sure your T-7000 is cool so it can be applied thinly, buy a genuine battery, keep your cool if something goes wrong and check a guide before you start your work! I look forward to the next smartphone or tablet repair I take on. I'm much more likely to do a good job and besides my time, I didn't lose anything of value here.
Thank you for reading. As usual, the accompanying YouTube video is linked below:
(Repair Wins Blog - Post #12)
(August 2026)
