Quietly, and without any publicity, Tesla has made changes to its website regarding the specifications of the Tesla Megapack. We can now see that the storage capacity has increased from 2.6 MWh to 3.9 MWh, which is practically a 50% gain, but it does point to the chemistry of the cells being LFP.
And that is because the increase in storage capacity has come at the expense of a 64% increase in mass, 33,000 pounds (14.97 tons), and an increase in dimensions in all its dimensions: it is 27% longer, 3% wider, and 17% higher. In other words, the energy density is worse, which suggests the use of lithium iron phosphate.
In electric vehicles, the mass must be at bay to reduce the consumption of moving the batteries themselves, for active safety reasons, etc. That’s not important, as Elon Musk explained in 2021: “However, for static storage, energy density isn’t that important because it stays in the ground. “
Indeed, the purpose of the Megapacks is to store a lot of energy, and whether they are bigger or heavier becomes a secondary consideration: they already need a lot of space, and the increase is very small in comparison, and as long as the architect is minimally competent weight gain is also bearable on the right terrain with the right foundation.
On the other hand, iron and lithium-based chemicals do not need cobalt, a controversial material where the vast majority of it comes from, the Congo, where it is difficult to guarantee that the supply does not disturb Western minds that think about human rights, labor, and environmental issues. On the other hand, there is plenty of iron on this planet to kick.
On the Tesla website in the US, you can order the new Megapack for 2.4 million dollars (California) with 1.9 MW of power and 2 hours of autonomy, and if they have 4 hours of autonomy, the price drops to 1, 93 million, although the power is lower 1 MW. On the Spanish website, there is no configurator and we are summoned to a contact form.