Sandy Munro of Munro & Associates tore down the Model 3's battery pack. He said that it is extremely well built and years ahead of anyone else in the industry. That starts at 28:21 into the video. I recommend watching the whole thing (on 2x speed on youtube), lots of new information and insights. Interestingly, I can't tell how the pack is cooled from the pictures. The battery is balanced +/- 0.2mA between "blocks" "I don't think you're going to get a bad battery cell" The battery pack is potted with some kind of compound "Oh my God, look at this" "I don't know how they put it together" "Look at the power density" "We started finding all this "magic stuff"" "This won't be going out any time soon (in reference to the pack)" "Anybody who ignores this car does so at their own peril"