A8 Parts Forum - Potential battery issue

Guys,

I was updating my maps today, and realising that this would be a lengthy process, I had the car on a battery charger while I did it.

The first 1.5 hours were fine, but then I went to check it shortly after and the car seemed "dead" no power on the MMI. The cluster still worked, but the parking brake light was flashing, both in the cluster, and on the brake button.

Then it said it did not recognise the key, which had been sitting in the car the whole time. I tried to start the car, but it wouldn't start, and a bunch of lights started flashing.

I tried locking and unlocking the car, which seemed to work initially (IIRC), but it doesn't respond to the key at all now. So the car was unlocked. I thought it might be the key battery, couldn't find a CR2032, so nipped out to get one. Got back and the car was now locked (charger still connected in the boot, with the boot open slightly). Changed the battery, and still nothing.

Is this likely to be a dead battery? The car is new to me, so I haven't really driven it much, but have noticed occasions where it would take a bit longer to start than other times. Hoping it is just a dead battery and not something more serious.

In the meantime though, the charger is still connected, but it does show the battery as ready and maintaining. It's an older Halfords charger though, been thinking about investing in a newer Ctek recently mind you. Battery looks reasonable, but no evidence of how old it is, and it's not like it would get manky in the boot of the car anyway.

However, how would I go about gaining access to the car if none of my keys are working? The boot is still open, but not sure how much that helps for opening the doors?