This project is about my current smartphone the Sony Xperia Z3. The Z3 is currently the ultimate phone for me. It is fast, has a very fast and responsive GUI, it has an amazingly vivid display and pictures look super sharp thanks to the BRAVIA Engine 2 and X-reality features, it has very well built and good looking stock apps like Walkman and the Xperia launcher. The phone is by now 1,5 year old and some tiny faults appear from time to time. When the phone was a little over a year old the waterproofing went faulty, I was washing the phone in the sink under running water (nothing unusual) and the adhesive seal of the bottom speaker broke. I noticed 2 hours later that some water leaked into the phone, the water was trapped in the bottom layers of the display. I seriously considered to open up the back of the phone to dry it but I decided to not do it and tried to dry it by heat and evaporation. I did this by opening all the flaps of the phone so water could evaporate and I connected the phone to a powerbank and I executed a cpu intensive stresstest on the phone and placed it then upright in an air-tight box with dry rice in it. There was very little chance of shorting the motherboard out because the motherboard is located in the top of the phone, the bottom part only contains a speaker, microphone, vibration motor and some antennas. I let the stresstest ran for approximately 4 hours and most of the water did evaporate and only very tiny bright-spots were visible at the bottom of the display.
After this incident I was thinking how cool would it look if the back glass of the phone was transparent. I have seen this mod on some phones like the iPhone 4s and the Samsung Galaxy S6. So, I ordered 3 backglass panels from china. The backglass is coated with a black coating on the inside. With the first backglass I tried to scrape the coating off with a glass scraper, this worked very well except around the camera hole in the glass, it broke at that place when I was scraping it. With the second backglass I tried to use some chemicals. I used alcohol, aggressive tile cleaner, acetone, white spirit and eventually drain cleaner. None of these worked except for the drain cleaner which took off a tiny layer of the coating but almost nothing, it also damaged the glass. I decided to give up on this project and I kept the chemically treated and the third backglass.
A week ago the battery of my phone failed. For over the last month if I ran a cpu intensive task and the battery percentage was below 40% the phone would shutdown due to low power immediately. I noticed something was going horribly wrong on an evening when I went running. I started my running session with the battery at 75%. I use a running app on my phone which uses GPS, mobile data and bluetooth (for smartwatch and heartrate strap). When I ran about 6km I wanted to pause a minute and send a snap to some friends. The moment I opened Snapchat the phone shutdown due to low power. This was not good so I decided to keep an eye on the battery by looking at its voltage. I noticed when I ran an intensive app the voltage drops to about 3v which triggers the low power shutdown mechanism of the OS. My phone is rooted and I installed an app that can override the low voltage shutdown of the OS. I do not recommend anyone to do this.
I noticed my phone has 3 low power shutdown mechanisms: The OS: if the battery goes to 0% the OS initiates the shutdown process, the percentage is measured by the voltage. The kernel: if the battery voltage drops below approximately 2.7v the phone just turns off and the phone displays the critical battery icon when you try to start it. This process does not initiate a shutdown process it just turns the phone off, there is a very high chance of data corruption and/or loss. In my case I lost all my saved wifi networks and my EQ setting were set to their default values. The last mechanism is the battery itself. The battery has a protection pcb on it’s terminal, this protects the battery from overcharging, overtemperature but also over discharging. This means that if the battery voltage drops below a set voltage the current is cut-off and the battery protection circuit needs to be re-activated by first charging the battery again.
I also installed a battery voltage widget so I could keep an eye on the battery. I noticed that when an intensive app executed the voltage drops to 3v but jumps right up to about 3.4v - 3.6v which is low but still not completely empty. I had nothing to loose with the low battery shutdown disabled because my intentional idea was to buy a new phone when the battery completely dies. I used the phone for about 2 weeks and it got worse every day. I decided that I want to replace the battery but it needs to be an OEM replacement battery (because of the china aftermarket batteries can explode thing). I found a company in Belgium they claim that they sell OEM replacement batteries. I ordered a battery and I thought why don't I try to make the last backglass transparent. I had the idea to sand the coating off with steel wool. I first tried it on the chemically treated backglass, and success it takes some time but the coating comes off and the glass doesn't get scratched at all. I sanded the third backglass and looks completely transparent and has no scratches at all. I replaced the battery, applied a new gasket on the backglass and placed the glass on the phone. It looks amazing. I also ordered a transparent back case the "Ringke Fusion Xperia Z3". The end result = a new OEM battery, a super geeky looking phone and a cost which is a fraction of the cost of a new phone.
PS: I did a capacity test on the old battery and it has 2182mAh left of the original 3100mAh. This means that the battery lost 30% of capacity after 1.5 year of intensive use.
PS: If you also want to do this and you get an error on the phone that says “Low memory, Could not run service” I found out this I caused by the absent of the NFC antenna. Just disable NFC and the error goes away.