MIT Electric Car May Rival Gas Models on Performance
Inside a plain-looking garage on the Massachusetts Institute of Technology's campus, undergraduate Radu Gogoana and his team of fellow students are working on a project that could rival what major automobile manufacturers are doing.
The team's goal is to build an all-electric car with similar performance capabilities of gasoline-only counterparts, which includes a top speed of about 161 kph, a family sedan capacity, a range of about 320 kilometers and the ability to recharge in about 10 minutes. They hope to complete the project, which they chronicle on their blog, by the third quarter of 2010.
Each member of MIT's Electric Vehicle Team works almost 100 hours a week on the project they call elEVen. "Right now the thing that differentiates us is that we're exploring rapid recharge," Gogoana said during an interview. He said that many of today's electric vehicles take between two to 12 hours to recharge and he doesn't know of any commercially available, rapidly recharging vehicles.
For this project, which is based on the body of a 2010 Mercury Milan Hybrid, the team plans to use lithium iron-phosphate cell batteries from A123Systems "because they have very low internal resistance and they've also been on the market for about three years," Gogoana said. The team's press materials added that, "electrochemistry [of the batteries] is less volatile than that of other types of lithium-ion cells, which makes these batteries desirable in applications where crash safety is a high priority."
The car's motor is an oil-cooled, three-phase AC induction motor from SatCon that weighs 138 kilograms including its controller. It was originally designed to be used in a 15,000 kg electric bus. So when it's installed in the 2,000 kg car, it should allow it to go from zero to 60 in under nine seconds and achieve a top speed of 100 mph at 12,000 RPMs.
In order to power the car's 250 horsepower, 187 kilowatt electric motor and give it similar performance to a gasoline engine, the team needs to wire a battery pack that includes 7,905 of the A123 cells. In order to rapidly recharge those batteries, they'll need 350 kilowatts. "That's enough power to blow the fuses on 20 residential homes at once ... so we'll be hooking up directly to MIT's power plant to get that kind of power," Gogoana said.
Obviously, not every home owner would have access to a power plant to charge their car, but Gogoana said the car could be charged overnight using a standard outlet. He hopes that once electric vehicles catch on and more charging stations are built, it will be "just as easy as filling your gas tank."
He said it's like "a chicken or the egg scenario" and wondered whether a charging infrastructure or the rapid recharge car should be built first. "We feel that right now it's easier to build a car that can do it rather than set up an infrastructure," he said.
Some companies are working on building nationwide charging stations. One such is Coulomb Technologies, which has about 40 ChargePoint networked charging stations across the U.S. The CT1000 ChargePoint can output 1.4 kilowatts, or 120 volts at 12 amps, which wouldn't be enough to rapidly recharge MIT's car. In fact, in order to charge MIT's car in about 10 minutes, the team needs 356 volts at 1,000 amps.
This isn't the first time the team has worked on an electric vehicle, though. In 2006, the year the team started, they modified a 1976 Porsche 914 to run on battery power. The end result was a car that could travel 161 km before it needed an 8-hour recharge on a 220-volt outlet. The battery pack contains 18 lithium iron magnesium-phosphate battery modules arranged in a series for a nominal pack voltage of 230.4 volts and a capacity of 100 amp-hours. The Porsche uses a 3-phase AC induction motor from Azure Dynamics, with a peak power of 74 horsepower and a top speed of about 161 kph at 12,000 rpm. It can go from zero to 60 mph in 20 seconds.
One of the biggest differences between the Porsche and the current project is the ability to completely charge in about 10 minutes. The team is also using the current project to do research on the impact of rapid recharges on the batteries. "Rapid recharging is a little bit harder on the batteries, but these cells have been charged in five minutes, so we're not being too harsh on them," Gogoana said.
Gogoana placed the cost of the project, excluding labor, at around $200,000, but much of the materials were donated and the Electric Vehicle Team isn't paid. The batteries alone hold a price tag of about $80,000, but Gogoana said that as more batteries and cars are produced, cost should be driven down.
While installing the 7,905 battery array is the team's end goal, they plan to test the car with a smaller battery array by mid-August. Once those tests are completed, they hope to finish the car, which includes installing the larger array and finalizing the rapid recharge system.
(Justin Meisinger in Boston contributed to this report.)