Exro Technologies Inc. aims to “enable electric mobility for the masses” with its Coil Driver technology, which acts as a replacement for the classic inverter.
The driver utilizes coil switching — the ability to switch electric motor configurations while in use, to maximize speed and torque. That concept is not new, but most electric vehicle (EV) models require multiple motors and gearboxes, while the Coil Driver eliminates that requirement.
An October, 2021 report from independent third-party tester AVL states the Coil Driver, in development since 2016, has a “motor (that) generates significantly more torque . . . It is also observed that the switching between different modes is seamless.”
An internal test from the Calgary-based Exro (EXRO-T) with a one-motor Humvee optimized with the Coil Driver resulted in 4,300 newton-metres (the measurement of torque, or Nm) of peak torque. This was compared against a two-motor Tesla semi class 8 truck, which produced 1,000 Nm of peak torque, and a three-motor GM EV Hummer which peaked at 1,285 Nm.
Now, the company is working with partners around the world to test the system in a variety of EV applications.
The Exro-Zero partnership
Exro first partnered with California-based electric motorcycle producer Zero in 2020 to combine the Coil Driver with Zero’s SR/S powertrain platform. In March, Exro announced its 100-volt Coil Driver increased power and torque in Zero’s SR/F motorcycles.
“The world of motorsports is all about power and speed. Electric motors will, eventually, be more powerful and more efficient, but first they have to get smaller, lighter and less complex. That’s why Zero approached us,” CEO Sue Ozdemir told SustainableBiz in an email conversation.
With just a base motor and inverter, the SR/F peaked at 199.46 km/h, data from the tests indicates. With the Coil Driver, its top speed was 226.49 km/h, an increase of 13.6 per cent. The maximum torque reached with a regular inverter was 189 Nm; with the Coil Driver it increased 20 per cent to 226.8 Nm.
The addition of the Coil Driver also resulted in an increase in maximum power. With an inverter, it achieved 70.1 KW and with the Coil Driver it grew 29 per cent to 93.3 KW.
While the 100-volt Coil Driver is intended for motorcycles, Exro also offers a low-voltage Coil Driver with up to 48 volts suitable for e-scooters. Its high-voltage Coil Drivers — up to 400V or 800V — are suitable for fleet vans, SUVs, trucks and buses.
“Auto and motorcycle enthusiasts crave speed and power, and they shouldn’t have to sacrifice that experience in the electric transition,” Ozdemir wrote. “Our Coil Driver has made it so that riders can experience high-quality performance while also being sustainable.”
Exro is also working with Zero on the San Francisco and London-based Untitled Motorcycles‘ limited edition Zero XP, a heavily-modified version of the SR/F. With the Coil Driver, Exro says the XP gained an additional 27.35 km/h on its top speed, bringing the figure up from 199.55 km/h to 226.91 km/h.
Currently, the XP produces 189.81 Nm in torque. The modified fleet will produce 219.64 Nm.
“To put it in context, that’s the same torque as a Lotus Exige S, but in a vehicle that’s 1,600 lbs. lighter,” said Hugo Eccles, Untitled’s founder and design director in a statement on the partnership.
Exro’s other partnerships
In 2021, Exro opened its U.S. headquarters in Mesa, Ariz. and expanded its Canadian presence with a Calgary manufacturing facility that can deliver approximately 100,000 Coil Driver units per year.
The company, founded in 2014, is partnered with several other global companies in various stages of integrating its low-voltage Coil Driver technology into their products.
In June 2021, the company announced an agreement with Linamar Corporation, a global automobile parts manufacturer. The companies will test the Coil Driver in Linamar’s eAxle electric drive solution for EVs. However, because of supply chain issues, delivery of the eAxle Coil Driver has been delayed until later this year.
Other partnerships include:
– With Mexico City’s Potencia Industrial S.A. CE D.V., it has been road testing its Coil Driver-integrated electric motor in a light-duty cargo truck for over six months.
– In February, Cleveland-based Land Electric Motorcycles ordered up to 2,000 Coil Drivers from Exro for use in its District motorcycles. It’s currently in the final stages of validation testing.
– Exro also partnered with Finland’s Aurora Powertrains Oy in February, 2020. Aurora’s electric snowmobile — called the eSled – is expected to be outfitted with the Coil Drivers starting later this year.
Outside of its many partnerships, Exro recently launched an EV design and engineering service in Detroit, Mich. to help automakers improve the performance of their EV models, lower production costs and expand the Coil Driver’s reach.
Exro projects the global market for EV inverters is expected to grow to over $9.7 billion by 2025.
“Right now, the industry is trying to apply a one-size-fits-all solution, but that’s not how electrification succeeds, and the ability to scale will determine who succeeds versus who fails,” Ozdemir wrote.
“That is why we’re hyper-focused on proving Coil Driver’s ability to optimize performance across any powertrain requirements — from a single motor, using a single, scalable solution — and we are constantly on the lookout for new companies to partner with.”