## Nissan unveils next-generation XTRONIC CVT, new 1-motor, 2-clutch FWD hybrid system, new fuel cell stack

##### 13 October 2011
 The new XTRONIC CVT features a sub planetary gear to enable a higher ratio coverage. Click to enlarge.

At a technical briefing in Yokohama, Nissan Motor Co., Ltd. unveiled its new generation XTRONIC CVT (Continuously Variable Transmission) for 2.0 to 3.5-liter engine vehicles as well as a new front-wheel-drive parallel hybrid system using the one-motor, two-clutch design earlier applied in the rear-wheel drive Infiniti M35 (earlier post).

The company also released its Next Generation Fuel Cell Stack (2011 Model) for Fuel Cell Electric Vehicles (FCEV). Through improvements to the MEA (Membrane Electrode Assembly) and the separator flow path, Nissan significantly improved the power density of the stack to 2.5 times greater than its 2005 model, achieving 2.5 kW per liter—the world’s best among auto manufacturers, Nissan said.

XTRONIC CVT. The new generation XTRONIC CVT model achieves an improvement in fuel economy of up to 10% compared to previous CVTs for comparable vehicles, based on in-house measurements using US (EPA) combined mode. The new transmission features a ratio coverage of 7.0 using a sub planetary gear to switch between low and high ranges, allowing smaller pulleys to reach higher transmission ratio coverage. This raises responsiveness on startups and at low speeds while allowing lower engine rpm at high speeds, resulting in higher fuel economy. Nissan also reduced friction by 40%.

 Main technologies of the XTRONIC CVT. Click to enlarge.

Combined with Adaptive Shift Control (which adapts shifting patterns to match each driver’s style and the road), the new generation XTRONIC CVT delivers responsive and powerful acceleration. It also helps keep the engine from revving too fast at high speeds and minimize noise. The new generation XTRONIC CVT will be introduced in North America from 2012, then globally thereafter.

By combining smaller shaft-diameter pulleys with a new and differently shaped belt, the range of ratios between the two pulleys has been expanded with only minimally increased axial distance. The resulting ratio coverage of 7.0 sets a new benchmark for CVTs for 2.0-liter-plus vehicles around the world, Nissan said.

The adoption of a more compact oil pump was achieved by reducing oil leak and reducing necessary oil pressure resulted from the interface increase between the pulleys and the belt. This, plus the use of specially formulated low viscosity oil, has reduced friction. Also approximately 60% of the component parts have been modified to reduce friction.

Adaptive Shift Control (ASC) senses each driver’s intentions through the way he or she accelerates and the choices made in handling and speed. Based on these preferences, ASC selects a gear ratio optimal to the specific conditions and the driver’s intention. ASC’s linear shift control function gives the driver a more direct sense of acceleration by coordinating engine speed (RPM) with vehicle speed as the car accelerates.

New hybrid system for FWD vehicles. Nissan’s new system incorporates one electric motor and two clutches into the new generation XTRONIC CVT and combines this with a compact lithium-ion battery and a 2.5-liter supercharged engine.

 The new hybrid system combines an efficient CVT with Nissan’s own one-motor two-clutch system; a downsized, supercharged engine; and a high-output lithium-ion battery. Click to enlarge.

The result is a compact, versatile powertrain that does not require a specially designed body. It delivers power equivalent to a 3.5-liter engine but with much better city and highway fuel economy. Nissan plans to release a new hybrid vehicle in North America in 2013, and later in global markets.

Fuel cell stack. In addition to significantly increasing the power density, Nissan molded the supporting frame of the MEA integrally with the MEA enabled stable, single-row lamination of the Fuel Cell, thereby significantly reducing its overall size by more than half compared to conventional models.

 Click to enlarge.

Additionally, compared with the 2005 model, both the usage of platinum and parts variation has been reduced to one quarter, thereby reducing cost of the Next Generation Fuel Cell Stack to one-sixth of the 2005 model.

From the Nissan pdf:
http://www.nissan-global.com/COMMON/PDF/TECHNOLOGIES/te_111013-01-06-e.pdf

'So can we expect to see a Nissan Fuel Cell Electric Vehicle (FCEV) coming round the corner soon?
“We are now ready to go to market at any time,” Yanagisawa says. “The only hurdle remaining is hydrogen
distribution. Give us the hydrogen and we’ll give you an FCEV. We’re good to go!”'

Pulleys, belts, and two clutches? Eww. Toyota and Ford hybrids have none of those unreliable designed-to-wear-out components.

Are complex mechanical marvels the best solution? It may be part of the solution to extend ICE life a few more decades.

Those improved, lower cost, higher power density FCs may have a bright future and could compete with batteries and ICE in many applications.

Two interesting developments.

This new improved fuelcell pave the way to broad applications for cars, suvs, farm tractors and machineries, motorcycles, cigarette lighters, chainsaws, lawn mowers, radio guided small hobby airplanes, tractor-trailers trucks, delivery vans, motorized campers, dump trucks, water powered electrical generations, buses, mining equipments, factory machineries, airplanes, ships, luxury liners, spaceships, portable computers, etc.

Nissan seam ready to commercialize this, they should sell home hydrogen makers instead of relying on third party hydrogen infrastructure.

Nissan are going flat out trying to get charge points installed for electric vehicles at the moment. I think they will make their move on hydrogen infrastructure later, perhaps around 2014.

Electric Home hydrogen makers, if ever affordable, would be ideal in our area with very low cost clean hydro electricity. In many areas, hydrogen makers could operate at low night time rates. Quick fill of the hydrogen tanks at larger commercial stations should not be a major change.

Renewable energy development is very important, and that includes BEV charging infrastructure, PHEV charging receptacles at work place and shopping places, and H2 filling stations, all linked to solar PV panels and wind electricity. Oil companies have plenty of money to invest in H2 infrastructure. The only thing needed is governmental policies to discourage fossil fuel usage while give incentives for renewable energy developments.

A lot of new jobs will be created, so the gov. should help in this regard. No need to spend more taxpayers money, however, the income tax rates should be rolled back to Clinton era, while tax shelters given for those who invest in renewable energy infrastructures, so, for those who want to invest in helping society and the world, there would be no effective increase in tax.

It's good that more and more auto mfg's are offering hybrid drive train. Nissan's HEV layout is similar to Hyundai except for the CVT in place of the 6-speed automatic tranny, and that's practical because much less development cost than Toyota's Hybrid Synergy drive, not having to pay royalty to Toyota, and sharing common drive train components with non-hybrid will reduce manufacturing cost.
Furthermore, an HEV with sufficient electric power is only one battery size away from being a PHEV, a notch higher in the Green ladder.

Nissan seems to have eggs in all baskets!

Hydrogen contains around 40kwh per kg, equivalent to a US gallon.
A home fuel cell might be 70% efficient to turn it into hydrogen, as an SOFC can be used instead of the less efficient PEM in cars.
So you are putting in around 57 kwh per kg of hydrogen.
At 10 cents/kwh that is $5.70, not counting the cost of the equipment. That is just about do-able, as the Hyundai Tucson for instance gets around 72 per kg, but hardly attractive. In reality a home hydrogen set-up would simply turn natural gas into hydrogen, as home fuel cells already are in Japan. Even that is not really an urgent need though, as there are not major problems is producing hydrogen, it is installing the pumps which needs to happen. DaveM, I'd love to see an SOFC in the mix, but I haven't been following their development that closely the last 6 months or so. Is anyone pursuing that path? DaveD: Panasonic for instance is hoping to get costs down for reforming NG in the home and using a fuel cell down to competitive levels as early as 2013. They have tens of thousands of higher cost ones in Japanese homes already: http://news.bbc.co.uk/1/hi/sci/tech/8563928.stm However, I was mistaken and Panasonic use a PEM, not SOFC: http://panasonic.net/ha/e/FC/doc01_02.html I had improperly generalised from Ceres use of SOFC for homes - I think the smallest they do is for one sharing power for a couple of homes though: http://www.cerespower.com/Technology/TheCeresCell/ Hmm, I seem to have trouble being accurate today. 'Tens of thousands in homes' s/be 'thousands'. DaveM, LOL No worries. Even for home use, SOFC is an interesting proposition to me. I was assuming the cost per/kWh was way too high, but would love to see them living in homes and being fed NG. I still think a PEM system could be useful as there would be ways to engineer it so the PEM could be swapped and recycled. Once they realise what is going on, the renewables crown won't be too happy. If you are piping gas into homes and using it not only to supply electricity but hot water, then it is somewhere between tough and impossible to ramp madly up and down to cater for the vagueries of wind. Most renewables rely on using huge quantities of NG rather inefficiently, and that use is built in for decades to come. The new reduced size Nissan 85 Kw FC is 66% lighter, has 63% less volume and cost 83.3% less than the previous model. This is a major breakthrough for automotive FCs. This new FC can be fitted under the floor. Wouldn't be surprised to see a Leaf-FC with 300+ miles range within about 5 years. Hydrogen supply and distribution will be a challenge to solve but it is not an impossibility. Henrik...Nissan many sell close to 25,000 Leaf this year...not by 2020. By 2020, Leaf-2, Leaf-3, Leaf-America and extended range Leaf-FC will sell worldwide at the rate of 500,000 a year and may be built in Japan, China, USA, EU, Canada, Australia and Brazil. You may be under-estimating what good (Nissan-Renault) management can do. Apparently they are aiming for a price of 10 million yen. I don't think sales will be massive at$130,000 each.

The mass produced price of the new 85 Kw FC is estimated at $90K/6 = about$15K. Of course one has to add the cost of the Hydrogen tank and controls. The vehicle cost should be much the same as a BEV without the batteries or a PHEV without the ICE and batteries or a HEV without ICE and most mechanical associated parts.

With continued evolution in FC and hydrogen storage tank, a $50K (2010$) mid-size FC car could be reality by 2020/2025 or so.

Hydrogen tank and controls would cost around \$2000-3000 currently.
Hydrogen filling stations can be built quickly and cost-effectively anywhere, requiring only an electrical supply, a high-pressure electrolyzer, storage tanks, and dispensing nozzles. H2 stations can take advantage of solar and wind electricity fed into it, thereby avoiding the use of fossil fuels, while solving the intermittency problem of renewable energy.

Yes, being able to store large quantities at relative lower cost is an asset for hydrogen energy carrier. Whenever, FCs cost is further reduced, it may become a worthwhile alternative for clean running ground PHEVs.

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