Nissan’s green Leaf uncovered

IT MAY seem a pie-in-the-sky fantasy now, but the day when you can drive home, plug in your car for an electricity recharge and then drive for up to 160km the next day is only two years away if Nissan Australia’s plans for its small electric vehicle (EV), the Leaf, come to fruition.

Production of the Leaf will begin in Oppama, Japan, later this year, followed by Smyrna, Tennessee, in 2012, and Sunderland, in the UK, in early 2013.

And despite rumours to the contrary, the Leaf will not have a quick-change, drop-out battery as promoted by recharge company Better Place, instead having a conventional permanent rechargeable battery, at least initially.

Nissan held a media workshop in Sydney last week, in part to explain the technology of its new EV that is expected to arrive in Australia next year for fleet trials and then go on sale in 2012.

Not only did Nissan’s senior EV staff from Japan address the media, but also the NSW energy minister John Robertson and Sydney Lord Mayor Clover Moore. The latter said the City of Sydney planned to install its first public recharge point at the end of this year.

The five-seater Leaf hatch will be positioned as a premium model in the small-car market dominated by the likes of the Mazda3 and Toyota Corolla.

Nissan says it believes it can sell the Leaf at a reasonable, comparable price with these vehicles, even though its senior vice president of global planning, Dr Andy Palmer, says the EV cost about 50 per cent more to develop than a convention internal-combustion car.

“We want this to cost you no more than say a Golf or a Toyota would cost you in the C-segment today,” Dr Palmer said.

The Leaf is within the loosely defined spectrum of the small-car class, at 4445mm long, 1770mm wide and 1550mm high. This makes the Nissan EV about 100mm taller than the Mazda3 but within millimetres for length and width.



The Leaf is also longer and slightly taller than another popular seller in the class, the Corolla hatch.

Unfortunately GoAuto was not given the opportunity to drive the Leaf, but we did get the chance to sit in a pre-production car and were given a demonstration of its IT capabilities.

Also, while Nissan has not released a full technical run-down on the as-yet unreleased Leaf, the company fleshed more of the previously fragmented information on how the new vehicle works and its features, courtesy of Nissan’s general manager technology and marketing, Kazuhiko Doi.

As he explained, the Leaf will have a mobile telephone link, allowing various functions such as cabin climate and charging times to be controlled via the internet and mobile phone.

“It is the most interesting part for customers of the Leaf. The Leaf will have 24-hours connection from a mobile.

“The customer can start the heating or air-conditioning from a mobile at home or office, and also receive updates on when new charging stations are added.” The cabin was trimmed in a pale beige that should’ve made the Leaf feel light and airy, but the Nissan EV seemed smaller inside than expected. The dashboard’s LED display showed information such as battery range via a scroll-through menu.

The rear seat space was acceptable rather than cavernous for the small class, but the cargo space under the hatch was a neat, squared off and relatively big area.

Nissan said that while the Leaf will have a conventional hydraulic four-wheel-disc braking system (except that it has regenerative braking as with the Toyota Prius and other such hybrids), along with drive-by-wire steering.

Options such as a sunroof will not be available until Nissan works out how to overcome the aero drag, which can compromise battery range.

The powertrain is a Nissan-developed 80kW/ 280Nm AC electric motor set-up that comprises an inverter, electric motor and reduction gear set. The output shafts connect via a CV joint to hub-and-carrier assemblies.

The Leaf will carry fewer flammable liquids than today’s cars, with engine oil, transmission oil and engine coolant unnecessary. It will only need brake fluid for the hydraulic brake system and windscreen washer fluid.

The Leaf employs a 24kWh laminated lithium-ion battery made in conjunction with Automotive Energy Supply Corporation.

Nissan expects the battery pack to last about five years, although heavy use will reduce the lifespan. Charge capacity also reduced as the battery nears the end of its life.

Quick charging will pump the battery to 80 per cent from zero in 26 minutes, while home charging using 220 volts will take around eight hours.

As battery range becomes low, the Leaf will go to a reduced output level to extend the range.

The charging point is under a flip-up hatch on the bonnet.

Mr Doi said fire risk – already well documented in lithium-ion laptop batteries – was not an issue, as Nissan’s lithium-ion battery in the Leaf features a stable constituent metal – manganese.

“The reason why we took 18 years to develop the lithium-ion battery was for reliability, basically, and the material for the battery is based on manganese,” he said.

“Manganese is a stable material, but it is difficult to extract power.

“We started from this stable material, and then work on how to get increased power.” Despite the relationship touted between charging company Better Place and Nissan for building new infrastructure, Nissan appears to have cooled the relationship. The Leaf is not designed to have its battery pack changed at a quick-drop station, as mooted by Better Place.

“This is not designed like that. Of course we can change it at our dealers, but it is not a quick drop system,” Mr Doi said.

When asked how the Leaf will cope with environments that have a steep terrain, Mr Doi said power consumption had increased significantly.

“We have a similar test course at Nissan, so we are doing experiments in hilly conditions. Definitely, the energy consumption is much higher. You cannot see 160km.” Nissan says most owners will charge the Leaf at home overnight, and while some areas of Australia might rely on brown coal to supply the grid, Mr Doi said zero-emissions solar panel recharging would be sufficient.

“I don’t know the average energy use in Australia, but in Japan’s case, the capacity of the Leaf battery is almost the equivalent of 2.5 days electricity usage in the house.

“From our studies – and of course it depends on the size of the solar panel – a panel on a normal house can charge enough to recharge a Leaf,” said Mr Doi, who floated the idea of community grids of EVs.

“In the future, we are thinking of using the Leaf to plug into the grid,” he said. “We want to make it to discharge, to share the energy. In the future we can see these types of communities, a local grid.”