While electric cars have been around since the turn of the 20th century, Mitsubishis MIEV technology breaks the mould. As implied by its name, the motors are located inside the cars wheels, as opposed to inside the body or chassis of the car. This new type of electrical motor benefits the car by taking up less space, allowing more batteries to be used, improving range and performance. Like many other electric vehicles, power is provided by a lithium-ion battery pack located inside the car. The MIEV system made its world debut this past May on the Colt EV with in-wheel motors propelling its rear wheels.
In the four months since its initial release, MIEV technology has taken one major step forward. The first-gen MIEV motor, like many other electrical motors, applied a conventional layout with the rotor (turning part) located inside the stator (the power-generating component). With the Lancer MIEV its the other way around. The rotor surrounds the stator, making for an empty doughnut-like hole in the center. This new design has three major advantages over the first-gen motor: it is more compact and lighter, reducing unsprung weight and therefore energy loss; the hollow space in the center of the unit is able to house discs and calipers for braking; and the speed reducer has been removed from the motor completely.
In order to uphold the Evos legendary performance name, which would require the new prototype to deliver performance that is equal if not better than the gasoline-powered version, each of the MIEVs motors produces 67-horsepower and a gargantuan 382 lb-ft of torque. In total, power output rivals the regular Evo at 268 total horsepower, but its 1,528 lb-ft of torque almost puts it in the same class as NHRA sanctioned top-fuel dragsters! OK, maybe not quite. Mitsubishi has yet to release any performance figures, but with more than three times the torque of the gas version available from zero rpm, this car will have a surreal amount of pull. Currently, the MIEV has a top speed of 111 mph and weighs 3,505 pounds, just 265 pounds more than the standard Evo IX. With a wheel providing thrust at each corner, this particular Lancer is significantly different than any production-series vehicle. Mitsubishi has gutted the standard turbo-four powerplant, including its gearbox, differentials, fuel tank and other driveline components. The lithium-ion battery pack used to power the car doesnt intrude into the cabin either, as everything fits in the space which the other drivetrain components previously occupied.
As exciting as the EVO IX MIEV is, Mitsubishi isnt about to rest on its highly charged laurels. Constant improvement is part of the program, with close focus on optimizing the cars all-wheel drive factor. Mitsubishis engineers are currently working on a program to individually distribute and adjust power to each of the cars wheels to mimic the fearsome grip and handling characteristics of regular Evos..
The previous design of the MEIV motor could only be used on the rear wheels due to conflicts with the steering system, one reason why the standard front-driven Colt was RWD. However, with this new kind of motor on board, and in use up front, the first four-wheel drive electric vehicle of its type is ready for action.
The Shikoku EV Rally is an annual event staged by scientists at the Shikoku University in Japan, which has been taking place since 1998. The main goal of the rally is to promote and educate the public about electric vehicles, and to give manufacturers a chance to do real-world tests on actual roads in Japan. This event will be important to Mitsubishi, giving its R&D team critical information on how the MIEV system reacts to the elements and constant use. Since the event started, Mitsubishi has become a regular participant, having entered models such as the Japanese-market FTO-EV, based on the Celica-sized FTO sports coupe, as well an EV-powered Eclipse.
Mitsubishi plans to development of the MIEV electric motor system, which it claims can be used for many different applications. While the Colt MIEV and Lancer Evo MIEV are purely electric, the system could be practically applied to next-generation hybrid vehicles, reducing the amount of product-specific or proprietary components, as well as in future fuel-cell vehicles. With core technologies relating to the innovative MIEV system already developed, Mitsubishi hopes to have some sort of vehicle powered by the systems brought to market by 2010.