That's approximately the same sort of operation as stealing the engine of a car. Not something you can do in a couple minutes with a battery powered angle grinder.
Since the batteries cost an order of magnitude more than a catalytic converter, this could justify criminals developing more sophisticated equipment to pull it off.
You know why I haven’t replaced the batteries on our 11 year old Nissan Leaf? Because I’m not quite ready to devote what will probably be multiple weekends to the job. So dispel any ideas you might have of someone snagging a battery pack in the middle of the night before I manage to release the hounds.
EV batteries are even more valuable than catalytic converters. Even at 200 or 300 lbs per battery pack, I bet we'll see EV battery thefts in the next couple of years.
I’m sure we’ll see some thefts but these are easily removed and small. Most EV batteries are the opposite on both counts — and if they were designed to be removable, they’d fit them with locks like on e-bikes.
It’s easy to run a sting operation jailing any business which will buy battery packs with the locks cut off.