Elon Musk is aggressively touting "zero rare earth" motors, behind which lies a major strategic ambition at the supply chain level.

On September 4, Elon Musk reposted an official Tesla update on X: the drive motor of the Cybercab does not use any rare earth elements, yet maintains exactly the same driving range. He added a follow-up note that this achievement was "extremely difficult" to deliver.

That single short sentence sent shocks across the entire rare earth industry and the electric vehicle sector. Reactions on Chinese internet platforms formed a standard process of Musk-style open-source viral marketing ecological feedback —

Some people exclaimed that the laws of physics were being challenged, some lamented that the "rare earth card" had been "invalidated", some stayed up all night pulling out the K-line charts of the rare earth sector to predict market trends. The comment sections were almost flooded with remarks claiming "Elon Musk has won again".

The level of excitement was exactly the same as that in March 2023. At Tesla's Investor Day that year, Colin Campbell, Vice President of Powertrain, casually stated that "the next-generation permanent magnet motor will not use any rare earth materials at all". The next day, the A-share rare earth index plunged by more than 5% at opening, leading Northern Rare Earth saw its market value evaporate by 4.3 billion yuan in a single day, and Guangdong Rising Nonferrous Metals nearly hit the limit down during trading.

Three and a half years later, that promise has finally been partially fulfilled.

But what is really worth analyzing is never "how he did it", but three points: which vehicle this technology is designed for, who the statement is targeted at, and why it was announced exactly at this moment.

The answer lies not in technology, let alone in the motor itself, but in the supply chain.

01

The Paradox of "Zero-Rare-Earth" Motors

We will not beat around the bush, and come straight to the conclusion first: Electric motors do not inherently require rare earth elements, but rare earth materials can greatly improve the overall performance of electric motors.

The basic principle of motors is simple to the point of being mundane: the stator generates a rotating magnetic field when energized, and the rotor follows the magnetic field to rotate, thus producing torque. So there is only one core question — where does the magnetic field of the rotor come from?

The value of neodymium iron boron permanent magnets lies in their "free bonus" property. You do not need to connect a wire to the rotor or pass any ampere of current through it. As long as the magnet is placed in position, a strong magnetic field will be generated, which is stable, demagnetization-resistant, and has an extremely high energy density. With the magnetic tiles made of neodymium iron boron, motors can be manufactured to be smaller, lighter, with higher torque density and better efficiency. Neodymium and praseodymium are responsible for the main magnetic properties, while dysprosium and terbium ensure the performance does not degrade at high temperatures.

▲ Neodymium iron boron magnetic tiles of various shapes are the core components of rare earth motors

That's right, this is a real "free lunch" at the physical level.

Therefore, the essence of "zero rare earth" is not a technological breakthrough, but a choice. Under the premise of forcibly removing the "free" magnetic field provided by neodymium iron boron magnetic materials, you have to find alternatives: you can pay with more electricity, or with larger volume, or with lower efficiency. You have to give up at least one of the three options, there is no way around it. Obviously, this kind of choice comes with inherent helplessness.

At present, there are clearly only three viable paths available in the industry.

The first path is the Permanent Magnet Assisted Synchronous Reluctance Motor (PMaSynRM) with ferrite. It uses a new generation of ferrite permanent magnet materials to replace neodymium iron boron magnetic tiles, and at the same time redesigns the rotor slot shape and magnetic circuit to maximize the reluctance torque. That means the output does not come from the strong attraction of the magnet, but from the reluctance difference of the iron core shape itself.

This path was proposed more than ten years ago, and it is still the most suitable rare-earth-free solution for passenger vehicles in terms of overall performance. The prototype developed by Hitachi Astemo achieves an output of 180kW, with a clear trade-off: its volume is about 30% larger than that of a rare earth permanent magnet motor with the same power.

▲ To put it simply, this is the traditional "magnet" that most people born in the 1980s and 1990s played with in childhood. The only difference is that with the latest formula, it may have stronger magnetic force, higher material strength through the latest process, and is combined with a brand-new rotor structural design. Essentially, it is an alternative solution when high-performance neodymium iron boron magnetic tiles are not available

Tesla is most likely taking this path. Three clues pieced together from existing information — redesigning the rotor core slot shape and magnetic circuit, adopting new composite magnetic materials (similar to anisotropic high-performance ferrite), achieving extremely high copper filling rate with enhanced temperature control. All clues point precisely to the combination of PMaSynRM and ferrite, rather than other solutions.

It is also worth mentioning here that Tesla claims the new motor is "18% smaller in volume and 25% lighter in weight" than its current high-performance drive unit. This comparison is most likely made against Tesla's previous generation of self-developed drive units, rather than against the rare earth permanent magnet motors of the same power obtained from Chinese suppliers after local production in China in 2019. What you compare with, how you compare, and how you describe it with words is indeed an art.

As for the second path, it is the Excited Synchronous Motor (EESM). This path completely removes permanent magnets, winds copper wires on the rotor, and uses current to generate a magnetic field. Given that nine-year compulsory education has long been popularized in China, Faraday's law of electromagnetic induction is a physics course content for the second semester of Grade 9 in junior high school, so we will not explain it in detail here.

BMW has already put this technology into mass production. The 210kW, 400N·m motor on its 5th generation eDrive does not contain rare earth elements, and the high-performance version on the iX M60 even reaches 360kW and 713N·m.

▲ Structure of the excitation synchronous motor rotor adopting flat wire technology

Of course all these come with trade-offs: current has to be transmitted to the rotating rotor through slip rings and brushes. This turns the core component of the motor, which was originally maintenance-free and could last as long as the vehicle, into a wearing part that relies on material science to maintain performance. Only with the latest graphite composite material technology can its service life be extended to 300,000 kilometers.

To solve the service life problem, ZF developed a brushless version (I2SM), which embeds the induction exciter directly into the rotor shaft, removes the brushes and slip rings, saves 90mm of axial installation space, and achieves parameters of 580N·m and 325kW, which is on paper comparable to permanent magnet motors. But it still cannot solve the fundamental problem: the excitation winding has to consume power all the time, its power consumption is naturally several percentage points higher than that of rare earth permanent magnet motors, and its peak efficiency is inherently at a lower level.

As for the last path, it is the simple and rugged asynchronous induction motor. The self-proclaimed high-performance motor that Tesla boasted about as early as 2014 is exactly this type, which was used on the earliest Model S and Model X. Its rotor magnetic field is induced by the stator current, and the slip brings additional I²R loss, so its efficiency is inherently at a disadvantage. Its only real advantage is that there is no magnetic drag at all when no current is applied.

Therefore, in many current dual-motor solutions for new energy vehicles, this type of motor is still reserved on the non-main drive axis — it is completely powered off during cruising to achieve zero drag loss.

Okay, the science popularization part is over, now let's look back at old accounts.

From 2016 to 2018, Tesla heavily promoted the concept of "rare-earth-free motors". At that time, all Model S/X vehicles were equipped with induction motors that had no rare earth magnets by design. Although their performance was significantly worse than that of rare earth permanent magnet motors, this did not stop Tesla from packaging it as a sense of superiority that "we do not need rare earths", and neatly integrating it into the "First Principles" public opinion communication system, becoming a small part of Elon Musk's narrative machine.

In this boomerang world, looking through the old statements in chronological order is very interesting —

In 2018, the long-range version of Model 3 was updated to use a permanent magnet synchronous motor;

In 2019, Tesla obtained the right to build a wholly-owned factory in China, the Lingang Gigafactory in Shanghai was put into operation, and Zhongke Sanhuan, Jinli Magnet, and Hengdian Dongmag successively entered Tesla's supply chain;

In 2021, Model 3 and Model Y were successively equipped with domestically produced drive motors, with higher power and torque than before, and the rear motor power of the Model Y all-wheel-drive long-range version was increased by as much as 22%.

▲ The existence of the Lingang Gigafactory not only helped Tesla improve motor efficiency, but also greatly reduced the company's marketing cost for a period of time

Since then, the slogan of "self-developed rare-earth-free motors" suddenly disappeared for five years. After all, the first rule of "First Principles" is that you can get the required supplies from the supply chain.

02

The Hidden Ambition Behind

So why is this slogan brought up again now? Because the situation of Musk's enterprises has changed completely. From the perspective of 2026, Musk has been firmly tied to the top US military, political and business system.

In its IPO prospectus, SpaceX marked the US government as "Customer A", its largest single customer. In 2025, the company's total revenue from the US government was about 4 billion US dollars. And the "Starshield" satellite network customized for the military is an indispensable infrastructure for the Pentagon.

Especially in May this year, the US Space Force issued two orders at once: one 2.3 billion US dollar contract to build a combat satellite communication network, and the other 4.2 billion US dollar contract, which aims to use SpaceX's launch capabilities to build the "Golden Dome" space-based moving target indication system. Therefore, this company is no longer a traditional commercial "contractor" in the ordinary sense, but a core support for the US military's global operations.

Once tied to this position, you can no longer make your own rules. The US International Traffic in Arms Regulations is in place, the nationality red line for personnel accessing sensitive technologies is in place, and the letter from the Senate requiring review of "whether Chinese capital holds shares through offshore accounts" is also in place. The loyalty test requires tangible deliverables — cleaning the supply chain is exactly that deliverable.

▲ SpaceX is a US defense subcontractor, the top tier of that category

But on the other hand, Musk's interests in China are too deep to be cut off.

Following the Shanghai Gigafactory launched in 2019, in February 2025, Tesla's first energy storage Gigafactory outside the US mainland was put into operation in Lingang, with an annual output of 10,000 Megapacks and an energy storage capacity of nearly 40GWh. More than 160 upstream and downstream enterprises have gathered around this factory in Lingang.

Tao Lin once publicly stated that more than 95% of the parts for the Model 3 and the new refreshed Model Y are produced in China. Tesla has cooperated with more than 400 domestic supply chain partners, and has introduced more than 60 Chinese suppliers into its global procurement system. In 2024, Tesla's sales in mainland China hit a new historical high of more than 650,000 units.

And the most critical link in all this is rare earth.

On April 4, 2025, China implemented export controls on 7 types of rare earth related items including samarium, gadolinium, terbium, dysprosium, lutetium, scandium and yttrium. Less than three weeks later, Elon Musk publicly admitted on an earnings call that the mass production of the Optimus humanoid robot was affected, and the company was applying for export licenses. He also added a very thought-provoking line: the Chinese side wants to ensure that these materials will not be used for military purposes, "which is obviously not the case, they will only be used for humanoid robots".

▲ Although the rare earth materials exported to North America are used by Tesla for the Optimus robot, it is hard to tell whether this technology will be used for military purposes...

The boss of a core contractor of the US military system guaranteed to the Chinese regulatory authorities that "the materials will not be used for military purposes" just for a few kilograms of magnets. You can carefully taste the subtlety of this situation: this is the real situation of Musk, with one foot in the Pentagon and the other foot in Lingang.

But everyone knows that this state cannot be maintained for a long time. As long as the two systems still share the same supply chain, any export control, any congressional hearing