You don't see many electric-powered sedans, sport utility vehicles or pick-up trucks rolling off assembly lines: bigger vehicles require bigger batteries and bigger electric motors that make them heavier and more expensive to manufacture.

It's a lucrative, untapped market that three Canadian automotive suppliers plan to aggressively target with a new, multi-speed drive train being developed in partnership with McGill University that increases efficiency, vehicle speed, and driving range without drawing more battery power.

The three-year project received $4.7 million from Automotive Partnership Canada to combine electric motor technology from TM4 Electrodynamic Systems of Boucherville, Quebec, with a multi-speed drive train from Linamar Corp.—a supplier in Guelph, Ontario.

"Partnering with Linamar to develop a smaller and integrated system—the drives, motors and power electronics—will open a larger market that we could become a leader in," says Stéphane Poulin, V.P. Engineering at TM4, which currently produces an electric motor for electric vehicles compact cars.

The new drivetrain would effectively leapfrog most competitors and overcome some of the major hurdles to mass-producing larger electric vehicles.

"The team of industrial partners is extremely complementary. There's no competition. Everyone's goal is to produce a highly efficient electric drivetrain that is flexible enough to address a larger segment of the car market, which also makes it more economical to manufacture," says McGill University researcher and principal investigator Benoit Boulet.

Montréal-based Infolytica Corp. will share its expertise in simulation to come up with the next-generation software needed to design these more advanced motors.

The new system has several competitive advantages. A smaller motor frees up room for a larger battery to provide a longer driving range. Combining that motor with a two-speed transmission also allows car manufacturers to meet two key performance criteria: "low-end torque so you have enough acceleration from stand still, and a reasonable top speed of around 160 kilometers per hour," says Boulet.

Multi-speed transmissions are commonplace in vehicles with combustion engines; however, the majority of today's EVs use a single-speed drivetrain—which means the motor is operating at reduced efficiency most of the time.

"Reducing manufacturing costs is a big issue," says Poulin. "When you go with more than one speed on the gearbox you can reduce the size of the power electronics and the motor. That means you can reduce the cost of your system."

The research team at McGill University began working with TM4 Electrodynamic Systems and Linamar Corp. two years ago on the first two-speed prototype, using a TM4 motor. Initial test results found that it performed better than the one-speed transmission. Next, the project will study three-speed and continuously variable transmissions (that allow you to move through gears without disengaging the engine) to see how they perform.

"This isn't blue sky research," says Boulet. "The companies want to have two-speed electric drive on the market in about three years."