Hello, about a year ago, I built this small system that runs linux and lives in my network cabinet:

The motherboard is Gigabyte H97N-WIFI, the manual to it can be found here: https://www.quietpc.com/instructions/gigabyte/ga-z97n-wifi.pdf

Now, every time the system loses power and booted up again it is stuck on BIOS screen, saying "BIOS was reset. Load defaults?"

Since it's running headless, it's a major pain. I think the reason for the message is that the CMOS battery went flat. So I'm looking to replace it. However I'm not sure how to go about it.

This is what the battery looks like:

[see below]

As you can see it's soldered to two wires, which are soldered to a plug that goes to the motherboard socket.

Am I screwed, or is it replaceable? If replaceable, then what do I need to buy (I have no idea what kind of battery this is) and how can I install it?