Notes

My phone battery has been getting worse and worse. Often dies before I've gotten to the office. I have had the phone around 2 years and still really like it. I have small hands and prefer a smaller phone so I can actually hold it in one hand! This greatly reduces my options and the only phones I can hold that are better than this one all have fingerprint sensor on back and usb c instead of headphone port, I would like to avoid both these 'features'.

I spent around £10 - Took me about 2 hours to do but I’ve never done anything like this before and some things took me a bit longer to figure out. (I only got one adhesive strip though there are two in the phone originally, one seems to be holding okay though.). Everything seems to be working. Phone charges, both cameras work, NFC works, headphone port works. So I am hopeful that I get to use this phone for a while longer now!

I ordered a battery that came with a toolkit but to be honest I ended up using things I already owned as the screwdriver head wasn’t the best fit and I had one floating around my toolbox that was better. The plastic wedge was too soft and started to get ruined quite quickly.

Battery+Tools (Didn't really use the tools provided):
https://www.ebay.co.uk/itm/Genuine-Replacement-Battery-for-Sony-Xperia-Z5-Compact-with-Tools-LIS1593ERPC/232890510270?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Battery Strip:
https://www.ebay.co.uk/itm/For-Sony-Xperia-Z5-Compact-Battery-Adhesive-Glue-Tape-Replacement-E5803-E5823/173345154839?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Video guide :
https://www.youtube.com/watch?v=M4_CFNWVGOU
Step by step guide:
https://www.ifixit.com/Guide/Sony+Xperia+Z5+Compact+Battery+Replacement/53303
(have put a copy of steps below in case site goes.)

Some extra comments about my experience to try and give anyone who doesn't think they can the confidence to try:

I read through this guide and watched the linked video before I started to get an idea of what I'd be doing.
I looked at phones available and had decided on what phone I was going to get if this went horribly wrong.

Made sure I wasn't going to lose anything by:

Moving all photos and videos onto my SD card.
Removing SD card
Synced Whatsapp
Plugged into PC and checked all the folders for anything I wanted to copy off (Some more photos were hiding in other folders.)
(I also got a list of all my open tabs off of chrome using developer tools as I love keeping tabs open! Prob not necessary unless your me.)

My additional notes about the steps:

Step 2 - I used a hair dryer to help warm up the adhesive. Used an old store card(credit card sized thing) to slide in and around edges, I also found that the middle of the long edge was the easiest place to get the card in, just prised it apart with my nails as suction cup was a bit awkward.

Step 3 - I was having real problems getting the screws out till I tried the other mini screwdrivers I owned. I used some sellotape to stop the screws rolling off. The NFC clip can be prised up using a flathead mini screwdriver to the top end in the frame and I just took it away from the frame rather than just loosening. The flashlight clip has some glue under so use a mini flat head screwdriver to prise it up on the left side (nearest camera) this should be able to flap forward hinging on the right.

Step 4 - the flashlight clip needs to be wiggled through out the back of the frame.

Step 9 - Releasing the flex connectors means getting the pale coloured bits to the left of the connector to stand upright (you might also have to peal off some orange plastic to get to this bit.) I used my nail to just flick them up, then the flex cables can be pulled out easily.

Step 11 - The battery adhesive strips are like the command strips for hanging pictures on the wall without nails in that when you pull the black tab it stretches out releasing it's grip... worked fine for me on one but the other one snapped mid pull and I couldn't get to the rest so I reused my store card to slide behind the battery till I hit the stuck area then used a sawing motion to slowly move through the glue, once the battery came away I used my nails and the card to scrape off the glue remaining on the motherboard.

Step 12 - I connected the battery to the motherboard connector before pushing onto the adhesive strip so I knew it was in a good position (I also managed to get the adhesive strip into a bit of a bunched up mess but I just straightened out as much as could and stuck onto it anyway) The battery I ordered ended up being slightly different shape to the one in there but it did fit in, was just a bit tighter trying to do some of the connections.

Putting back together:

I left the NFC antenna till the end so I could clip it back into the frame and then stick it down so it was in correct position.
Some of the connectors can be a bit fiddly to get lined up and pushed back in but can be done.

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Introduction

While your Sony Xperia Z5 Compact battery drains quickly after long period of use, you can follow this guide to replace the battery yourself.

Step 1 Battery

Power off and remove SIM card tray.

Step 2

Heat up the back cover to soften the adhesive.

Place the suction cup to open a gap from top side, then insert guitar picks and slide it to cut the adhesive underneath.

Heat up the back cover to soften the adhesive.
Place the suction cup to open a gap from top side, then insert guitar picks and slide it to cut the adhesive underneath.
Remove back cover.

Step 3

Twist off 10 Phillips screws all.
Loosen NFC clip and flashlight clip.

Step 4

Remove the plastic bracket.
Pry up and remove back frame.

Remove front camera.

Step 6

Remove rear camera.

Step 7

Remove loudspeaker.

Step 8

Pry up motherboard assembly from this side. There are three flex connectors connecting the motherboard underneath. So pry up the motherboard assembly gently.

Release charging port connector.
Remove plastic protective bar.
Pry up motherboard assembly from this side. There are three flex connectors connecting the motherboard underneath. So pry up the motherboard assembly gently