There is, an clearly kWh is the unit.
Indeed, however the amout of deceleration you'll get in M/S^2 depends on how heavy the car is, and whether you're going downhill or uphill so it's not a direct indicator of the sense of deceleration that can be applied between cars or all driving conditions.
Nissan don't allow towing with the front wheels on the ground in any state. Why not if just "leaving the car turned on in Neutral" is adequate?
They don't need to "allow" it because it's FWD, so it's easy to tow the car with the front wheels raised off the ground and avoid the whole situation.
The problem with them saying it was allowed is that the usual reason for a car being towed is that it has broken down or run out of charge. Clearly it can't go into neutral if the battery is flat, and even if it wasn't they can't trust the tower to make sure the car is turned on properly, handbrake and parking brake released and in neutral. And what if the battery went flat during the tow and shut down with nobody in the car to notice ?
If the battery wasn't flat and the drivetrain was working normally (and thus safe to tow in neutral) there probably wouldn't be any reason to tow it eh ?
Better from a liability and warranty perspective to just say don't tow it with the front wheels on the ground. That says nothing about whether it's OK to coast in neutral for a couple of minutes, vs towing a broken down car for potentially 50+ miles.
Neutral is a software construct in an EV, nothing changes mechanically. It's the same as finding the "zero point" on the accelerator. If it was dangerous to enter neutral in motion it would be trivial to lock it out in software. The fact that they haven't says it's not dangerous as there are so many other safety interlocks in the car right down to not being able to turn the car on or engage drive without the brake pedal pressed.
Incidentally, the Ion, which is RWD, does state that towing is allowed with the driven wheels on the road - provided that speed and distance are limited and the car is turned on in ready mode. (Thus the drive inverter powered up) This is probably an acknowledgement of the fact that not all tow trucks are flat beds and towing the car backwards with the rear wheels off the ground would be dangerous. With the Leaf being FWD they can just say don't tow with the front wheels on the ground.