Hi guys, I know that this video is in Russian, but worth looking at for those who can understand what he is saying: https://youtu.be/t2QdPbgbSdA
For the rest of you, here is a summary:
-- This guy previously swapped 30 kWh pack into a 24 kWh LEAF. It did not work initially, but after he also swapped control modules it worked fine and reported correct capacity, estimated range, etc.
-- 40 kWh battery can't be used as a direct replacement, but he believes that modules can be swapped. Physical dimensions are the same, but some wiring, connections, and control units are not compatible.
-- Internal module design is different, offering a tighter fit, see his prior video: https://youtu.be/r6JeVZbNi6Y
-- His plan is to purchase a salvage 40 kWh pack and do a demo where he actually upgrades an old LEAF to 40 kWh.
As a side note, here is a video from Ukraine Tesla guru who visits LEAF aftermarket shop where they dismantle LEAF battery packs, test each module, and reuse those modules that are still good. What is interesting about this video is that they highlight that, in a typical battery, heat damage to the modules in the middle is much worse that damage to perimeter modules. They link it to a lack of thermal management in LEAFs (I know, big surprise). https://youtu.be/SVTtXvGmBvU