A UK-based transmission specialist company called Zeroshift has made a significant breakthrough that could shape the way we drive electric vehicles in the future.
The firm has devised a multi-speed gearbox for electric vehicles that requires no clutch – instead a damper inside the gear hubs and electronic control of the motor allows the ratio changes to be seamless. This means there is no interruption in torque allowing the motor to run at a higher efficiency, which in turn extends the range and battery life by as much as 10 per cent.
Zeroshift's multi-speed transmission concept.
This potentially significant breakthrough would replace the synchromesh in a conventional manual gearbox with interlocking rings that change ratios. It also uses electronic control of the electric motor to match shaft speeds and an integrated passive damper system within the drive hub that can isolate vibrations. With sealed pockets of silicone fluid and mechanical compression springs, the shifts are virtually unnoticeable to occupants.
Now the concept is being developed using Zeroshift’s proprietary gear-shifting system. It is hoped that it could allow electric vehicle motors to be downsized and keep them running for longer at medium loads and speeds with peak efficiency of 95 per cent possible.
It is also believed that the improved efficiency could extend battery life. At the moment, electric vehicle drivers often drain the cells due to range limitations. However, improving the motor efficiency uses less of the energy stored for a journey, which eases the discharge-recharge cycles and cuts recharge time.
