A magnet weaker than the one it replaces
Most electric vehicle motors worldwide, 70% to 80% of them, are permanent magnet motors, built around a magnet that holds its own magnetic field rather than needing continuous current, according to research firm JMK Research and Analytics. A ferrite magnet is 1 kind used in that design, made with no rare earth material in it at all. Proterial, a company that manufactures magnets, states that a ferrite magnet motor avoids neodymium, a rare earth material, along with 2 other rare earth elements, dysprosium and terbium. But a ferrite magnet itself produces a weaker magnetic field than a magnet made from those rare earth elements, so a motor built with one needs a design change to produce the same power.
A Newcastle University thesis measured exactly how much weaker. Its traction motor design specified a ferrite grade called FB9B, with a remanent flux density, the strength of the magnetic field a magnet produces on its own, of 0.44 tesla. A later chapter rebuilt the identical motor with the magnets swapped for a neodymium rare earth grade, remanent flux density 1.2 tesla, with no other change made. That is about 2.7 times stronger, a figure calculated here from those 2 numbers. The design also had a peak torque target, the turning force the motor was built to deliver at its strongest point, of 270 newton meters. With the ferrite magnets, the design fell short of that target. With the rare earth magnets swapped in, and nothing else changed, it met and exceeded the target.
Remanent flux density, the strength of the magnetic field a magnet produces on its own, measured at 20 degrees Celsius, in the same traction motor design from a Newcastle University thesis.
Show the numbers
| Ferrite FB9B grade | 0.44 |
| Neodymium rare earth grade | 1.2 |
What the switch costs in weight or speed
The magnet maker Proterial ran its own simulation of what it takes to make up for that weaker field. To match the output of a neodymium magnet motor at the same rotation speed, a ferrite magnet motor needs to run 30% heavier. To match that output at the same weight instead, it needs to spin 50% faster.
From a simulation the magnet maker Proterial ran on its own motor design, comparing a ferrite magnet version against a neodymium magnet version built to the same output.
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| Keep the same speed, add weight | 30 |
| Keep the same weight, add speed | 50 |
Against that cost sits a much lower price. JMK Research and Analytics puts rare earth magnet material at about 6000 rupees per kilogram, against about 400 rupees per kilogram for ferrite magnet material, about 15 times less, a figure calculated here from those 2 numbers. The same research firm estimates a rare earth free motor design could cost 30% to 60% less to manufacture than a rare earth based design.
Rupees per kilogram of magnet material, as estimated by JMK Research and Analytics.
Show the numbers
| Ferrite | 400 |
| Rare earth neodymium based | 6000 |
A ferrite motor already certified
Ola Electric built its own ferrite motor and became the first automotive manufacturer in India to get this kind of government certification for one, according to a filing the company made to 2 stock exchanges. Global Automotive Research Centre, a government testing body in Tamil Nadu, tested the motor under Ministry of Road Transport standard AIS 041, and certified it on October 6, 2025.
The tests found the ferrite motor matched the net power, the usable power a motor actually delivers, of a rare earth permanent magnet motor in both variants tried, 7 kilowatts and 11 kilowatts. Ola Electric first showed the motor in August 2025, and plans to build it into its product lineup between October and December 2025.