Eventually, the battery failed. It would report being fully charged, but only run for a few minutes before switching off. Recalibrating and resetting the battery statistics failed to improve the situation.

So, time to buy a replacement Nexus 6 battery. Cost under £15 and delivered on the slow boat from China.

I followed this excellent tutorial from iFixit. Here are my notes.

• Buy proper tools. You'll need a T3 Torx head. That's quite an uncommon size, so I picked up this torx set which also contains a set of tweezers.
• Melt the glue gently. Most of the glue had already perished on mine, but for the elusive splodges you'll want to gently apply heat. I used a hot water bottle filled with boiling water. I rested the phone on top of it for a few minutes and then gently peeled it apart.
• These are delicate electronics. Be very careful. Don't tug.
• Once you've undone all 22 T3 screws, the phablet opens into two pieces.
  
• As you can see, the old battery was wrecked
  
  Although, to be fair, some of that disfigurement is caused by prying off the glue. Remember to recycle your old battery safely.
• When replacing the battery, you have to consider whether you want to glue things down again. If you don't, there's a slight risk that some of the precise connections could shift and you'll have to disassemble everything to realign them. I cheated an used a small piece of sticky tape to keep the Qi in place.
• You don't need to use the Qi inductive coil - although it also contains the NFC antenna as well. If you break it, you can buy a replacement fairly cheaply. The quad connector which wraps around the battery is for Qi charging. The long straight cable is for the NFC.
• I didn't screw everything back together until I was sure it had worked. I put in the four screws for stability and then tested both the USB and Qi charging. I also tested the NFC using a basic app.
• Success!
  
• The battery came partly charged - I reset the battery statistics just to make sure it was working. Once fully charged, I'm going to use it until it is completely empty.

There you have it! For around £25 including tools, I've got a brand new battery - and a little ego boost knowing I can do basic repairs to complex electronics.

To add insult to injury, many many many people have discovered that the back peels off due to a systemic manufacturing defect.

After only a few weeks of using the device, I found that the back cover was beginning to come loose on my phone. I thought it might be a swollen battery, but it appears to just be crap build quality and non-existent QA.

When I charge the phone via Qi (the wireless charging standard) the phone gets hot - as does the charging plate. This heat is enough to partially melt the cheap glue which holds the device together.

On picking up my phone the other morning, I could easily pry up the corners of the cover. Not great. Motorola's advice to me was that I should send it back to them and - if I hadn't changed the firmware - they'd re-glue the device for me and send it back a week later. Again, not the service I expect for a £500 handset.

So I decided to take matters into my own hands.

Using a plastic knife, and aided with a little extra heat from a hair dryer I removed the back in under a minute.

This is what it looks like :

The thin layer of glue gave way easily. I had initially thought about cleaning it off with a little isopropyl alcohol and sticking it back on with something stronger.

Given my dissatisfaction with the back (too slippery and too curved) I decided to stick the phone in a cheap, clear TPU case.

I think it looks rather neat - the circuit design of the case nicely complements the actual circuitry of the phone.

The case adds much needed friction to the back of the phone and protects it from bumps and knocks. It can't do anything about the upside-down USB port though!