Ooooh DizzC, thats sooo good I love teardowns

I searched for the model number of the battery pack (LP404252ARU), and it seems that it is manufactured by BYD Corp. of China. They seem to be a pretty big company. It is not listed on their product page, but the pattern of the model number fits in.
On that certificate sheet from Underwriter Laboratories I found numerous battery pack model numbers from renowned electronics companies like Nikon and Nokia, so they have either manufactured third party replacement batteries for their devices, or maybe even those companies' original OEM batteries, but that remains unclear.

Good to know that the KT is so easy to open, in case the battery dies. I don't think it is glued in there like mad, probably some glue dots or tracks of glue around the edges. Glue costs money. Most likely the battery will come out by applying careful force.

It also seems that BYD is a pretty serious automobile copycat, just search for it, pretty... "astonishing"... Well, they are certainly not the only ones.