Tesla dry electrode process for 4680 cells: from Battery Day to mass production

From Battery Day 2020 to a viable dry cathode

At the 2020 “Battery Day” event, Tesla unveiled-complete with plenty of fanfare-a significant technological step designed to speed up battery manufacturing while bringing costs down.

The development is known as the dry electrode process (for both anode and cathode) and, for Tesla, it has long been treated as something close to the holy grail of battery production. By removing chemical solvents and several energy-hungry stages from the manufacturing line, the company said it could lower the cost per kWh by up to 20%.

Even so, getting the technology to a point where it made commercial sense turned out to be a slow and complicated journey. While Tesla had already managed to apply the approach to the anode, achieving the same outcome on the cathode side proved far more demanding, largely because cathode materials are chemically and structurally much more rigid.

Nearly six years later, Tesla has now managed to manufacture these cells using a fully “dry” method, no longer relying on the traditional, slower and more expensive processes for producing the cathode.

Why the dry cathode proved tougher than the anode

The key obstacle lay in the nature of the materials involved. Compared with the anode, the cathode’s constituent materials are harder to work with when trying to form a stable, uniform layer without using a liquid solvent-making scale-up considerably more challenging.

What is the difference between dry and wet cathode processes?

In the conventional cell-production method, the cathode’s active materials are blended with a liquid solvent to form a kind of “slurry”. This mixture is then coated onto metal foil and dried in an oven. The overall workflow depends on extremely large drying ovens, as well as expensive systems for filtering and recovering solvents-and it also consumes vast amounts of energy.

With the “dry” approach, the active materials are combined as a dry powder with a polymer binder (plastic). The mixture is then pressed to create a thin, solid film directly onto the current collector. This removes the need for ovens and solvent-recovery systems, cutting 70–80% of the energy used and reducing the cost per kWh by up to 20%.

Tesla also managed to bring binder usage down to under 3%, increasing the share of active material and, as a result, improving the battery’s driving range.

Elon Musk highlighted the significance of the achievement on the social network X, where he praised the teams for what he described as an excellent accomplishment.

Making the dry electrode process work at scale, which is a major breakthrough in lithium battery production technology, was incredibly difficult.

Congratulations to the @Tesla engineering, production and supply chain teams and our strategic partner suppliers for this excellent…

• Elon Musk (@elonmusk) February 1, 2026

Already in production in Tesla 4680 batteries

The dry electrode process (anode and cathode) is already being used in the series production of Tesla’s 4680 batteries. Reportedly, the Cybertruck is the first model in the brand’s line-up to receive them. In addition, some versions of the Model Y produced at the Texas Gigafactory are also being fitted with 4680 batteries.

---