Suzuki is working on a two-speed transmission for its electric cars
On January 11, 2023, Suzuki finally unveiled the eVX concept car. “The world’s first 100% electric car” from a Japanese manufacturer.
Electrifying its range has not been easy for a “small” brand that doesn’t have as many resources as big manufacturers like Suzuki. However, the Japanese managed to get out of the game with cars mild hybrid (48 V) followed by conventional hybrids and plug-in hybrids.
Also, thanks to the commercial partnership with Toyota that started in October 2016, Suzuki was able to carry out its technological transformation, thus allowing to reduce the development time of these new technologies, but above all the sharing of costs between the two companies. ..
Nevertheless, the development of an electric vehicle such as the eVX requires a large research effort that is financially burdensome to the Japanese company, hence the need for technological partnerships.
The latter is due to Inmotive, the Canadian company behind Ingear, a two-speed transmission for electric vehicles. According to Inmotive, this technology “Increases EV range by 15% and improves acceleration by 15%”, reasonably priced but not listed. As for the weight of this transmission, it would be negligible according to the manufacturer.
Suzuki’s next electric cars will be equipped with this transmission. On the other hand, the manufacturer has not specified whether the eVX will be equipped with this new transmission.
A precedent with the Porsche Taycan
Today, the entire electric vehicle fleet is equipped with a simple reduction mechanism, but the addition of a multi-speed transmission can improve efficiency and performance. In any case, this is the path chosen by Porsche (Taycan), Audi (e-tron GT) and Rimac (Concept_One, Concept_Two and Nevera). Thus, the two German manufacturers have installed a two-speed automatic gearbox connected to the rear engine, and the front is connected to a reduction gear. The second gear is activated as soon as the limit of 150 km/h is exceeded.
As for Bugatti’s owner, Croatian Rimac, its hypercars have one gearbox for each engine. Thus, their two rear engines are each mated to two-speed gearboxes, while their two front engines are linked to single-speed gearboxes.
Typical torque and power curves of an electric vehicle motor. © Geotab Inc.
This technological trend is not only good. Installing a gearbox adds complexity with limited benefit. The weight gain is inevitable and the cost of extra maintenance as well as extra parts just doesn’t seem justified. So it will be interesting to see how the Ingear transmission will fare in a production EV.
CVT transmission in Bosch
A very high-speed transmission dedicated to electricity is increasingly of interest to sector players such as Bosch. The German equipment manufacturer wants to equip electric vehicles with a continuously variable transmission (CVT). Preparation of the project in July 2021 Digital Bosch has announced that it has developed a transmission called the CVT4EV. Tested in the Volkswagen e-Golf, it gained about 4% efficiency.
The equipment manufacturer explained that at low speeds, the gearbox adopts a shorter ratio to improve acceleration. Torque also helps optimize towing and passing performance. At high speeds, a longer ratio increases top speed and improves efficiency, especially at steady speeds.
This CVT4EV box would be suitable for midsize cars, sports cars and even light electric utilities.
It remains to be seen whether other mainstream automakers will follow Suzuki’s example by equipping their EVs with gearboxes.
