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Video: Battery Day Speculation - Solid State Battery?

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I don't expect it to be solid state, but probably a different set of incremental technologies.

The solid part of solid state is the electrolyte. The point of a solid electrolyte is that it prevents the formation of lithium dendrites on the surface of the negative electrode. This lets you use lithium metal for the negative electrode in place of graphite that gets intercalated with lithium ions. This means a solid state battery, with a lithium metal negative electrode can have a higher specific energy than a regular li-ion. The downside to a solid electrolyte is that Li+ ions don't move through a solid as easily as through a liquid/gel, meaning a solid state battery has high internal resistance. The positive electrode (the heaviest part) of a solid state battery is the same or something similar to that of a conventional li-ion, so there's not a huge advantage there.

Lots of research teams and startup companies are working on fixing the problems with solid state batteries, but Tesla hasn't been associated with any of them.

There are a series of technologies that Tesla has been associated with, which could get close to the benefits of the solid state battery. Tesla has been researching electrolyte additives that prevent dendrite formation. Also, it's known that Tesla has been adding silicon to the negative electrodes. Putting them together, we could see a new, silicon-based nanoparticle material for the negative electrode which allows it to absorb a much higher ratio of lithium ions than conventional graphite.

Tesla also bought out a company called Maxwell, which has a dry electrode manufacturing process. The process allows the positive electrode material to be applied to the separator as a dry powder rather than as a slurry. This process doesn't use volatile solvents, making it better for the environment and easier to get air permits in California. But it also avoids the loss of ~10% of the cathode material's lithium after the first charge-discharge cycle.

This is just my speculation.
 
cell chemistry change?? Tesla corporate secret - so maybe not - Perhaps new cell construction?

new battery pack (no more modules) shared across models - perhaps carbon fiber to save weight

48 volt CyberTruck wiring, smaller wire saves weight too
multiplexing - saving ~700 meters of wire

another GigaFactory

cost reduction in vehicles - heat pumps, more Al castings

Loop electric Van (investigate small street Van too)

PS - there is no battery tech that Tesla ignores - investing, R&D too. cell production equipment
 
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