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Updated Nissan LEAF available in Japan; range improved by 14%; new motor uses 40% less dysprosium

Nissanmotor
Nissan’s grain boundary diffusion process allows it to reduce the use of dysprosium in the traction motor in the updated LEAF by 40%. Click to enlarge.

Nissan Motor Co., Ltd. released the updated Nissan LEAF electric vehicle (EV) in Japan. The battery-electric LEAF, now in its second iteration, is now available at Nissan dealers nationwide. With the updates, range at full charge on the JC08 cycle is expected to be 228 km (141 miles)—a 14% improvement over the original version of the LEAF with a 200-km range (124 miles) on the JC08 cycle.

Among the enhancements to the updated LEAF is a newly developed electric motor that will reduce the use of the rare earth element (REE) dysprosium (Dy) by 40% compared to conventional EV motors. The new synchronous AC motor offers the same power output (80 kW) as its predecessor, but less torque: 254 N·m for the new motor, vs. 280 N·m for its predecessor.

In addition to the LEAF, Nissan plans to use the lower dysprosium motor in future hybrid electric vehicles (HEVs).

Using a neodymium-based (NdFeB) magnet, motors used in electric vehicles need to be compact in size with high performance. Dysprosium is added to neodymium magnet’s to strengthen heat resistance. In conventional electric motors, dysprosium is uniformly added to the neodymium magnet, but the new motor—developed in a joint effort with Nissan’s suppliers—features a breakthrough grain boundary diffusion process.

Instead of uniformly adding the dysprosium to the magnets, the new process distributes dysprosium around each crystal grain’s boundary, which improves the magnet’s heat resistance while maintaining high performance levels. The result of this process is a 40% reduction in dysprosium use while still keeping heat-resistance levels comparable with conventional electric motors.

Nissan says this new electric motor is only the first step in the process to limit the use of rare earth elements. The company plans to adopt the grain boundary diffusion process for its hybrid motors, with the goal to ultimately achieve zero usage of dysprosium in other components as well.

With all its the enhancements, the updated LEAF has reduced its power consumption: 114 Wh/km on the JC08 vs. 120 Wh/km earlier. (Battery pack capacity remains the same: 24 kWh.) Other enhancements to the basic LEAF powertrain include:

  • The high voltage power electronics (inverter and DC/DC converter) and electric motor were integrated, resulting in a 30% volume reduction and a 10% mass reduction.

  • Weight is reduced by about 80 kg (176 lbs) compared to previous model. This was achieved via the combined powertrain unit, integrated functions, streamlined battery module and case structure, and use of lighter parts.

Driving performance is enhanced by improved steering response in the medium-speed range and optimized suspension characteristics associated with weight reduction. In addition, changes to the regenerative brake control system enable more efficient power generation when the brakes are operated.

Auxiliaries also have reduced power consumption with a heat-pump cabin heater, heated seat for all seats, heated steering wheel and heat shield ceiling.

A long-life charging mode—in which the battery is charged to 80% to extend the battery life—is now available in any charging mode.

The navigation system also provides a “Stop-off charging spot guidance” function, “Power-saving route guidance” function and “Battery capacity at a destination forecast” function which can allay potential range anxiety New ways to search for and locate charging spots easily and quickly. There is also a “Charging spot availability information provision” function, “Quick charger location display” function and “Unavailable charging spot display” function.

At present, there are approximately 400 sales outlets in Japan that are equipped with quick chargers. In order to offer even better convenience and accessibility for LEAF owners, Nissan plans to expand the availability of quick chargers to 700 sales outlets in Japan. When the expansion is completed, one-third of dealers will be able to offer quick charging service.

Since its debut in December 2010, Nissan has sold more than 43,000 units of the LEAF worldwide.

Comments

Davemart

ChrisL:

There are two issues here.

The first is that if anyone did buy the Leaf instead of leasing it, which seems a pretty daft thing to do now that the facts are in, then without an assured plan or price for a battery replacement then depreciation will by horrific right up until the point that the true costs are known.
Effectively almost all of the value of the car will disappear over 5 years, as selling a Leaf with maybe 80% only of its battery capacity left doesn't bear thinking about.

The second issue is that the only reason electric cars appear in any way reasonable in cost is due to the $7,500 subsidy.

This is not available on replacement batteries and that seems to me to be the likely reason that Nissan has not even made any plans to offer one.

So at present prices batteries may cost around $500 kwh, and the Nissan pack perhaps $12,000.

That is not a reasonable repair cost to pay on a 5 year old car, and even the most generous assumptions on falling battery prices make dubious sense when other chemistries should comfortably last as long as the car.

In my view Nissan have chosen the wrong chemistry, particularly in view of their not putting in liquid cooling, and competitors like the Chevy Spark simply will not have this problem.

Lad

A few positives: less weight of about 175 lbs, consolidation of units and more efficient units, a new battery chemistry from Hitachi (LiFePo, I believe) with better temperature specs...all translates to Nissan trying to reduce the cost of the car and at the same time increasing the range. When I bought my car, #669, I figured that this would be the case, i.e., that Nissan would continue to make improvements in each generation of the car.

I am disappointed at the progress of their battery technology because I fear it is still too expensive and their attempts to increase the car's range have been pretty weak. It seems to me they need to improve the range to an honest 100 miles at freeway speeds of 65 mph; never mind the fancy EPA specs, they mean nothing unless they can meet this practical requirement. That means a more energy dense battery; I don't see it yet and until they listen to the early adopters and can do this, they will not meet the expectations of most U.S. drivers.

Davemart

'a new battery chemistry from Hitachi (LiFePo, I believe)'

Huh? I was aware that Hitachi were now a second tier supplier, but had they gone to LiFePo then presumably they would make a big deal of it, as the cycle life is radically better than manganese spinel, and would if not solve at least greatly reduce durability issues.

Still manganese spinel AFAIK.

Mannstein

What remarkable nonsense just to drive an over priced electric vehicle. The consumer is now put into the position to worry about a stable supply of dysprosium, lithium, vehicle range, and battery life. Who needs it? It's going from the frying pan into the fire. When the enabling technology finally arrives call me, in the meantime go back to the lab.

Davemart

@Mannstein:
Absolutely!
Its a great thing that oil dependence causes no problems, does not cause wars and will exist in abundance forever from its abiotic supplies!

kelly

"It seems to me they need to improve the range to an honest 100 miles at freeway speeds of 65 mph; never mind the fancy EPA specs, they mean nothing unless they can meet this practical requirement."

"..and until they listen to the early adopters and can do this, they will not meet the expectations of most U.S. drivers."

Makes a lot of sense, esp. with US distances.

Another 20% range improvement could meet this minimum.

With web sites announcing multi-factor battery improvements weekly for years/decades - no problem.

Since gas prices have often doubled in weeks - repeated gas prices doubling during 5 or 10 years of future vehicle ownership seems likely.

Also, electric hardware costs fall over the years and a one moving part power train is cheaper to maintain then a thousand ICE moving parts.

wintermane2000

For the next 10-15 years you would have to be rather daft to BUY an eletric car instead of lease one.

SJC

Pay for batteries or fuel.

wintermane2000

Yup but still for now its FAR smarter to lease the car and thus its battery then it is to own it. Specialy concidering some of these companies are going to go belly up.

SJC

The replacement cost for the batteries will be included in the lease payments, so you pay for that anyway. It is the residual value that matters, I would not say Nissan is likely to go "belly up".

Herm

Perhaps it is best to think of replacing batteries as maintenance, not "repairs".. like a very expensive set of tires.

Mannstein

@ Davemart

What makes you think if dysprosium, or lithium get tight there won't be wars over those commodities as well? Like I say from the frying pan into the fire.

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