2017 15" MacBook Pro Battery Loose

A rattling (more of a hearty 'clunk') sound has formed in the last few days when I rotate my 2017 15" MacBook Pro. It feels like something heavy inside is moving around the unibody enclosure. Could this be the battery that has come loose, and would apple repair to free of charge as my device is pristine?

I did notice a solvent smell being emitted from my MacBook Pro over the years, but I thought it was just solvent residue from the manufacturing process. (I had this before with an older MacBook, but the smell disappeared after a few months). I wonder if the heat generated by the CPU over the years has caused the adhesive to cure and lose its bonding properties?

The last thing I want to happen is the loose battery to fatigue the connections or even the connector ribbon to the main board, meaning I have to fork out for a repair and new battery, for something which is workmanship related.