Its all relative... the Model 3 battery is significantly more energy dense than the Model S battery and appears to be lighter weight. How much of this is packag

Its all relative... the Model 3 battery is significantly more energy dense than the Model S battery and appears to be lighter weight. How much of this is packaging (2170 vs 18650 form factors) vs chemistry improvements is really hard to know. It is widely believed that the Model S prototype was using a much larger battery with 2170 cells and likely at either the same or a somewhat lower weight than the previous Model S. The truck has the benefit of being tall, so the pack is multilevel. The roadster will use at least two levels as well as it has a very thick pack, and obviously at its price point they can afford to use the absolute highest density cells on the market.