Rare-Earth Free Magnet Motors

Tesla, one of the leading electric car manufacturers, has been at the forefront of technical advancements in every key component of electric vehicles, from their 4680 cells to their gigapress. Recently, at a shareholder meeting, Tesla announced a shift to rare-earth-free motors. However, based on the images they showed, it appears that they are still using permanent magnet-based motors. This suggests that they might switch to ferrite-based magnets or alternative material magnets.

One possible alternative material for magnets that Tesla may be using is iron-nitride-based magnets. These magnets are made from abundant and cheap iron and nitrogen by manipulating the crystal structure of iron nitride. The compound forms when iron and nitrogen react at high temperatures and pressures. Initially, iron nitride has a hexagonal structure that is not magnetic, but by applying a magnetic field and heat treatment, it can be transformed into a tetragonal structure that is magnetic. The resulting iron nitride magnet has a high coercivity, which means it is resistant to demagnetization by external fields.

Iron nitride magnets offer several advantages over rare-earth magnets. Firstly, they can be mass-produced at less than half the cost of rare-earth magnets. Secondly, they can have up to three times higher energy density product than neodymium magnets, making them suitable for applications requiring high performance and thermal stability such as electric motors and generators. Additionally, iron nitride magnets have a higher Curie temperature than neodymium magnets, which means they can maintain their magnetization at higher temperatures. This makes them ideal for use in electric vehicles.

Despite being known since the 1950s, iron nitride magnets have been challenging to manufacture. However, companies like Niron Magnetics have invested decades of research into developing these magnets and now claim to be able to mass-produce them. Iron nitride magnets have a wide array of applications not only in motors but in other devices as well, making them an exciting area of research and development.

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At Naxatra Labs , We are developing high performance axial flux motors for electric vehicles and other applications. We aim to bring it into mainstream industry and disrupt the existing status-quo, and become the leading axial flux motors suppliers in the electric vehicle revolution.