(August 2, 2009) In conjunction with the grand opening of its new world headquarters in Japan, Nissan is unveiling its all new battery electric car the LEAF. The LEAF is a five door, five passenger compact car that is slightly larger than the current Versa hatchback. This will be the first of a series of electric vehicles to be introduced over the next several years by Nissan and its alliance partner Renault.

Over the past two years Nissan has been heavily promoting its vision of electric vehicles for the future. In that time it has formed nearly 30 partnerships with government and private entities to promote the build-out of the infrastructure necessary to support the widespread use of electric vehicles. These include programs such as the collaboration with Better Place and the Israeli government to create a network of charging stations and several similar partnerships with governments and utilities in the United States.

The LEAF is five door hatchback similar in size to the current Sentra. It has an overall length of 175 inches with a wheelbase of 106.3 inches. It spans 69.7 inches and stands 61 inches tall. It's body styling is unique to the lineup with a short sharply downward sloping nose that contains the electric motor that drives the front wheels. So far Nissan has not quoted a specific mass for the LEAF but the battery pack weighs about 440 pounds. The automaker claims the overall weight should be close to a similarly sized conventional car like the Sentra thanks to the reduced mass of the motor compared to an engine and transmission. That should put the LEAF in the neighborhood of 2,900-3,000 pounds.

The 80 kW AC motor produces 206 lb-ft of torque which is enough for a top speed of about 90 mph. Nissan's aim with the LEAF is to produce a real world usable electric car that is also affordable so this vehicle is optimized specifically for this purpose. By creating a purpose built EV, rather than a conversion from an existing car, Nissan claims to have been able to reduce the complexity of the car.

Like other Mitsubishi, Toyota, and Daimler, Nissan has aimed to ensure the availability of its battery supply through a joint venture. In this case Automotive Energy Supply Corp (AESC) is jointly owned by Nissan and NEC. The first AESC factory is in Japan, but additional battery plants will be built in the US and Europe as Nissan and Renault expand electric vehicle applications.

As most automakers and battery suppliers are doing, AESC has developed a flat, laminated cell design that can be packaged with greater density in a car. The cells in the LEAF battery pack are arranged into 48 modules and installed below the floor and rear seat of the car. The AESC cells have a rated power density of 2.5 kW/kg while the energy density is 140 Wh/kg. That is slightly less than the 150 Wh/kg claimed for the LG Chem cells used in the Chevrolet Volt. The total capacity of the pack is 24 kWh and Nissan claims the LEAF will run about 100 miles per charge based on the LA4 test cycle.

LA4 test cycle

The LA4 cycle is an urban driving test that runs 7.5 miles and has an average speed of only 19.6 mph. The maximum speed is 56.7 mph on one short stretch but for the most part the driving is at 30 mph or less. The frequent starts and stops are likely to aid the range somewhat through the car's regenerative braking capability, but in real world conditions drivers are more likely to see less than 100 miles of range especially in particularly hot or cold weather conditions.

Because the range of electric vehicles is much shorter than for internal combustion vehicles and "re-fueling" is more problematic, Nissan has incorporated a number of features in the LEAF to mitigate "range anxiety" for drivers. The LEAF actually has two separate charging ports. The ports are located at the front of the car under a flap above the bumper.

The standard port on the right is the new SAE standard J1772 port that will incorporated by most automakers developing plug-in vehicles. This five pin coupler supports charging at 110-220 volts as well as two way communications. The communications aspect will be important in the future to allow for vehicles to be identified at public charging stations for billing purposes. A full charge from a 200V home AC outlet is expected to about eight hours.

The second larger charge port on the left supports quick charging from a 480 volt / 50 kW three-phase supply. With this charger, the battery can be replenished to 80 percent of full charge in under 30 minutes. Once the battery gets to 80 percent of capacity, the charging rate is slowed down to prevent overheating and overcharging the pack which could cause permanent damage to cells. If high power charge ports are available at public locations, drivers would be able to take a short break or going shopping and get their vehicles topped up. However, it is likely to be a number of years before such stations are available. Currently all of the announced plans for public charging, use only 110 or 220V outlets.

A second feature that Nissan has incorporated to address range anxiety is its connected mobility IT system. The LEAF will be able to display the car's current maximum driving radius on the navigation screen based on information from the battery management system. The system will also be able to download the location of public charging stations and display them on the map allowing drivers to find the closest place to top up.

Drivers will also be able to get an application for smart-phones like the Apple iPhone that will allow them to remotely manage the car's climate control system. A user could use the phone or a standard computer web browser to activate the climate control system while the car is still plugged in. This would allow the car to use grid power for the most energy intensive part of the air conditioning or heating cycle, that of bring the car from ambient temperature to a comfortable one. The same functionality can also be activated with an in-car timer that can be pre-programmed.

The LEAF will go into production at Nissan's Oppama Japan factory in late 2010. It will initially be leased to government and commercial fleets for field testing. Later in 2011 and into 2012 production rates will be ramped up as the LEAF becomes commercially available in markets around the world. Nissan plans to add production of both batteries and the LEAF at its Smyrna TN factory in 2012 with funding from a $1.6 billion loan recently approved by the US Department of Energy under the Advanced Technology Vehicle Manufacturing Incentive Program. Nissan won't quote a specific price yet but has indicated that it should come in well under $30,000 in the US market. That price will presumably be after taking into account various tax incentives.
 

NISSAN LEAF Specs

Dimensions
Length: 4445 mm / 175.0 in.
Width: 1770 mm / 69.7 in.
Height : 1550 mm / 61.0 in.
Wheelbase: 2700 mm / 106.3 in.

Performance
Driving range over: 160km/100miles (US LA4 mode)
Max speed (km/h): over 140km/h (over 87 mph)

Motor
Type: AC motor
Max power (kW): 80kW
Max torque (Nm): 280Nm

Battery
Type: laminated lithium-ion battery
Total capacity (kWh): 24
Power output (kW): over 90
Energy density (Wh/kg): 140
Power density (kW/kg): 2.5
Number of modules: 48
Charging times: quick charger DC 50kW (0 to 80%): less than 30 min; home-use AC200V charger: less than 8 hrs
Battery layout: Under seat & floor