A History of the Electric Motor: Faraday to the Hub Motor

The motor in a modern electric three-wheeler is, in its essential principle, older than the telephone, older than the light bulb, and very nearly older than the postage stamp. Almost everything that has changed about electric vehicles in the last thirty years is battery, electronics and software. The motor itself was largely solved in the nineteenth century.

That is worth understanding, because it tells you where the real engineering risk in a vehicle sits — and it is not usually in the motor.

A year earlier, the Danish physicist Hans Christian Ørsted had noticed that a compass needle deflected when placed near a current-carrying wire. That was the discovery that electricity and magnetism were connected at all.

In 1821 Michael Faraday, then an assistant at the Royal Institution, worked out how to turn that force into continuous motion. He suspended a wire so that it hung into a pool of mercury with a magnet at the centre; when current flowed, the wire circled the magnet indefinitely.

It did no useful work and drove nothing. But it was the first demonstration that electrical energy could be converted into sustained mechanical motion — the entire premise of every motor that followed.

Continuous rotation needs the current in the rotating part to reverse at the right moment, or the rotor simply swings to a position and stops. The commutator — a split ring with sliding contacts that flips the current direction twice per revolution — solved that, and it defines the brushed DC motor to this day.

• •William Sturgeon built a commutator-based DC motor in 1832 that could actually turn a load.
• •Moritz von Jacobi built a motor in 1834 powerful enough to drive a boat carrying passengers on the River Neva in 1839.
• •Thomas Davenport, a Vermont blacksmith, patented an electric motor in 1837 and used it to run a printing press and a small model railway.

Davenport’s business failed, and the reason is instructive. His motors worked fine. He was powering them from disposable Daniell cells, and the zinc they consumed cost far more than the coal an equivalent steam engine burned. The technology was sound; the energy source was uneconomic. Electric traction would keep hitting that same wall for the next 150 years.

At the Vienna exhibition, a technician working with Zénobe Gramme’s dynamos reportedly connected two of them together by mistake. The first, being driven mechanically, generated current. The second, receiving that current, started spinning on its own.

The lesson was that a generator and a motor are the same machine running in opposite directions. That symmetry is not a curiosity — it is the basis of regenerative braking in every modern EV, where the traction motor is briefly operated as a generator to recover energy that would otherwise become brake heat.

Brushed DC motors have an inherent weakness: the brushes physically rub, so they wear, spark and need replacing. For an industrial motor expected to run continuously for years, that is a real maintenance burden.

Nikola Tesla’s AC induction motor, patented in 1888, dispensed with them entirely. Multiple AC windings arranged around the stator produce a magnetic field that rotates by itself; that rotating field induces current in the rotor, and the rotor is dragged along after it. No electrical connection to the rotating part is needed at all.

The induction motor is rugged, cheap, and needs almost no maintenance. It became the workhorse of twentieth-century industry, and it is a large part of why AC won the standards war of the 1890s — a fight we cover in how power transmission works. Mikhail Dolivo-Dobrovolsky’s three-phase designs from 1889 onwards made it practical at industrial scale.

From roughly 1900 to 1960, motors did not change fundamentally. They got better materials, better insulation, better manufacturing and better efficiency, but a 1950s induction motor would be entirely recognisable to Tesla.

What they also did was disappear. Electric motors became invisible infrastructure — in pumps, fans, lifts, machine tools, trains and household appliances. Today, electric motors account for a very large share of all electricity consumed worldwide. Most people could not name a single one in their home, and would be wrong about the count by a factor of ten.

The real revolution was not in the motor. It was in what could be put in front of it.

The brushless DC motor replaces the mechanical commutator with electronic switching: sensors detect rotor position, and semiconductors energise each winding at the right instant. You get the ruggedness of having no brushes together with the fine speed control of a DC machine. This was impractical until power transistors became cheap and reliable.

The second shift was permanent magnets. Neodymium-iron-boron magnets, developed in the early 1980s, are dramatically stronger than the ferrite magnets available before, allowing a much smaller and lighter motor for the same torque.

Three pressures are shaping current development, and none of them is about making motors more efficient in the abstract — a good modern traction motor is already well above 90% efficient across most of its operating range.

• •Reducing rare-earth dependence. Neodymium and dysprosium supply is concentrated in a small number of countries, which is a commercial and strategic risk. This is driving renewed interest in induction motors, switched-reluctance designs and ferrite-magnet motors that avoid rare earths entirely.
• •Integration. Motor, gearbox and inverter are increasingly designed and packaged as one unit rather than three, saving weight, cost and cabling.
• •Control sophistication. Most of the perceived difference between a smooth vehicle and a jerky one is the controller’s software, not the motor’s iron and copper.

If you are assessing an electric three-wheeler, the motor is rarely where the risk is. Brushless hub motors are a mature technology built by many competent suppliers, and a well-made one will usually outlast the vehicle around it.

The components that decide whether the vehicle is still working well in three years are the battery, the controller and the wiring and connectors — which is where our daily inspection routine spends its attention, and it is not an accident that the motor barely features in it.