I reported your, Avocet's, and others info (on battery repair) to my mate yesterday, who was very intrigued.
He did ask though, how are they going to do that? The batteries make up the entire floorpan....
I said I reckoned that 1. these people are specialists; there'd be no use being proficient in fixing a battery, if you were unable to actually get at it; and
b. your car came from a production line. I therefore imagine that Jag managed to get the batteries in there in an efficient fashion, and not send each cell in, one at a time under the arm of a Borrower, through a teeny little gap somewhere............
He's optimistic about what you've all told him, as am I
Now; all I have to do is get my Director to get me an EV.......................................
It's easy in some ways, harder in others. Theoretically, it's very easy, because the battery pack is bolted to the underside of the car. You just unplug the cables, take the bolts out, and it's on the floor! In practical terms, however, it's bloody heavy! A big battery pack can be up to half a ton. We do this at work. (Obviously, don't tell NutJob, but the factory burns down twice a week. which is getting a bit wearing now... ). We lift the car on a conventional 2-post hoist, and then we have a little scissor lift on a trolley that goes under the battery.
There are IMI courses that the technicians have to go on - Levels 1-4 I think, and various PPE (the big rubber "clown shoes", apron, gloves, etc). The car will have a battery removal procedure, but it's basically a case of making sure everything is isolated and then just disconnecting the hoofing great connector.
And making sure it's not live:
once the battery pack is unbolted, you just lower the scissor lift and wheel it out from under the car. On some cars, there would be heating / cooling lines to disconnect as well.
We've never taken a battery pack apart, we just need to remove them to do certain jobs on the car. However, there's usually a sheet metal lid over the whole pack, with many screws holding it in place, and a bead of sealant. On some cars, you'll destroy the lid, peeling it off the sealant. Once that's off, you'll see the modules (boxes of cells) inside there. Also the battery management system. Remember that before even starting this, the Battery management system will have logged which cell(s) is/are faulty, so it's not like you have to take out all 3000 cells (or however many there are) and test each one. The diagnostic software will tell you that Cell#1435 is poorly, and that's in Module 6, so you just hoick out that module and swap the cell. (Seems they DON'T have a big ribbon that you pull, to get the cells out)!
In many ways, easier (and cleaner!) than working on an ICE. Obviously, you can't do that on a Tesla Model Y, with its adhesive-flooded "structural" battery pack, but you can do it on other EVs. "Caveat Emptor" & all that!