The Secret of Tesla Battery Day

For years, in discussions about future batteries, fanboys have touted the big breakthrough that would make batteries better, cheaper, safer, lighter, etc. — as if touched by a magic want. That is not how progress in science or engineering is made. It is always the dwarf standing on the giant’s shoulders that sees new possibilities beyond the old horizons.

This Tesla Battery Day revelation was not different in principle. The big difference was not one dwarf climbing upon a giant’s shoulder, but an army of dwarfs climbing on top of each other on all the giants’ shoulders they could find.

From the raw materials to the finished product, every aspect of battery making was torn apart into its smaller parts, and those again in even smaller parts. Each part was studied, analyzed by the Tesla dwarfs looking for ways to improve, or better yet, omit, the part.

The lithium supply problem was tackled by devising a way to get it out of the clay in Nevada. (Remember when there was supposed to be lithium for only 5 million EVs or 25 million hybrids in the world?) That is expected to be enough to replace the complete USA auto fleet with fully electric vehicles. The expensive high-grade refined nickel availability problem was attacked by encapsulating raw nickel grains in a polymer coat that make it as good as or better than the expensive version for a fifth of the price. And there were other improvements in raw materials mining and processing.

There was the battery cell size optimization, increasing it from 21mm in diameter by 70mm in height (2170) to 46mm in diameter by 80mm in height (4680).

The roll that is the actual active part of the battery is being better connected with the + and – poles of the battery by removing the connecting tabs. Or you could say a giant tab connects every part of the roll to the pole. See for yourself in the video of battery day.

Then there’s Tesla’s plan to make the roll with a revolutionary new process, dry electrode production. Again, it’s an idea that needed many inventions to make it work. Tesla bought the company that was developing the process and are now building the factory to test, scale, and refine the process. They are on their own 4th update of the machinery since acquisition.

Tesla reviewed the complete concept of the battery that drives a car. A normal manufacturer looks only or mainly at its own production process. What comes before or after it is for its suppliers and customers. That results in improvements in only a part of the process or product. CATL and others have put in extra effort and improvement by creating cell-to-pack technology. Tesla went a giant step further. It started at the search for raw materials, and ended with a new way to put cells in cars. Tesla used, as Zach Shahan coined the phrase, “Cell to Car” (CTC) technology, removing not only the modules but the pack all together. The battery actually makes the car lighter. For the details of how this is accomplished, watch the Battery Day video or wait for a more detailed article.

Simplified: the dry electrode tech makes the cells stronger. Embed those cells in a fire retardant that provides structural support and the glued-together cells become a structural part of the skateboard between another innovation, the giant casts for the front and back of the chassis.

The secret of Tesla Battery Day was that there was not one big innovation. There were dozens of big, bigger, and smarter innovations that all helped each other. That the whole is bigger than the sum of the parts is clearly also true for innovations. It was just demonstrated in a great presentation by Tesla.

This article just points to the tip of the iceberg of what was presented. Expect many more articles describing and explaining the many innovations that are coming.

Don’t expect to see the results in Tesla’s vehicles tomorrow, though. The first that results can reach production is in about 18 months. It could take three years before all what was shown today is implemented in high-volume production.