It's mostly Panasonic.
https://ev-database.org/cheatsheet/energy-consumption-electr...
From your link this doesn't seem to be true. The short range, non awd model 3 has great efficiency. Other model 3s are also good but clearly not anything particularly far ahead as there are a bunch of other models from other manufacturers with similar or better efficiency.
Looking at other Tesla models makes it clearer that they aren't anything particularly special. Even the model y, which is basically model 3 with minor body tweaks is basically middle of the road, model s and x are even worse.
Their EPA ranges were found to be overstated across models, then there was that recent thing with falsified dashboard data.
I wouldn't say Tesla has advantages in any field, quite the opposite and mostly because of the Elon factor, which basically is just another synonym for NIH.