Toyota FCV Mirai launches in LA; initial TFCS specs; $57,500 or $499 lease; leaning on Prius analogy
18 November 2014
|Mirai. Click to enlarge.|
In addition to the vehicle’s introduction in Japan, Toyota launched the Mirai—a four-door, mid-size fuel cell sedan with performance that fully competes with traditional internal combustion engines—in Los Angeles on the eve of the Los Angeles Auto Show. The hydrogen fuel cell electric vehicle re-fuels in 3–5 minutes, travels up to 300 miles (482 km) on a full tank, and will be available to customers in California beginning in fall 2015. Additional markets will follow, tracking the expansion of a convenient hydrogen refueling infrastructure.
The Mirai uses the Toyota Fuel Cell System (TFCS), which features both fuel cell technology and hybrid technology, and includes proprietary Toyota-developed components including the fuel cell (FC) Stack, FC boost converter, and high-pressure hydrogen tanks. The TFCS is more energy-efficient than internal combustion engines and emits no CO2 or substances of concern (SOCs) when driven. The system accelerates Mirai from 0–60 in 9.0 seconds and delivers a passing time of 3 seconds from 25–40 mph. Fuel consumption figures are to come.
|Mirai powertrain. Click to enlarge.|
Toyota FC Stack. The new Toyota FC Stack achieves a maximum output of 114 kW (153 hp). Electricity generation efficiency has been enhanced through the use of 3D fine mesh flow channels. These channels—a world first, according to Toyota—are arranged in a fine three-dimensional lattice structure and enhance the dispersion of air (oxygen), thereby enabling uniform generation of electricity on cell surfaces. This, in turn, provides a compact size and a high level of performance, including the stack’s world-leading power output density of 3.1 kW/L (2.2 times higher than that of the previous Toyota FCHV-adv limited-lease model), or 2.0 kW/kg.
|The compact Mirai FC stack generates about 160 times more power than the residential fuel cells on sale in Japan.|
Each stack comprises 370 (single-line stacking) cells, with a cell thickness of 1.34 mm and weight of 102 g.
The amount of water on fuel cell electrolyte membranes has a substantial influence on electricity generation efficiency. Control of the amount of water is carried out using an internal circulation system for circulating the water created when generating electricity—meaning the Toyota FC Stack, unlike systems used in all other previous Toyota fuel cell vehicles, does not require the use of a humidifier.
The stack, with a significantly reduced size, fits under the front driver and passenger seats.
|“Our fuel cell vehicle runs on hydrogen that can be made from virtually anything, even garbage.”|
—Akio Toyoda, Toyota Motor Corporation President/CEO
High-pressure Hydrogen Tanks. Two tanks with a three-layer structure made of carbon fiber-reinforced plastic and other materials are used to store hydrogen at 70 MPa (approximately 700 bars or 10,000 psi). The three layers are:
- Inner layer: plastic liner (prevents hydrogen leakage)
- Middle layer: carbon fiber reinforced plastic (structural element)
- Surface layer: glass fiber reinforced plastic (protects outer surface from abrasion)
Compared to the high pressure hydrogen tanks used in the Toyota FCHV-adv model, tank storage has been increased by approximately 20% while both weight and size have been reduced to achieve a world-leading 5.7 wt% .
The front tank holds 60.0 liters, the rear tank, 62.4 liters. Total hydrogen storage mass is about 5 kg.
|Under the hood. (Power control unit on top, traction motor beneath.) Click to enlarge.|
Electric traction motor and battery. Current-generation hybrid components were used extensively in the fuel cell powertrain, including the electric motor, power control and main battery. The electric traction motor delivers 113 kW (152 hp) and 335 N·m (247 lb-ft) of torque. Toyota is using a NiMH battery in the Mirai.
Safety. Toyota began fuel cell development in Japan in the early 1990s and has developed a series of fuel cell vehicles, subjecting them to more than a million miles (1.6 million km) of road testing. In the last two years alone, fuel cell test vehicles have logged thousands of miles on North American roads. This includes hot testing in Death Valley, cold testing in Yellowknife, Canada, steep grade hill climbs in San Francisco and high altitude trips in Colorado. The Toyota-designed carbon fiber hydrogen tanks have also undergone extreme testing to ensure their strength and durability in a crash.
This extended legacy of research and development is reflected in Mirai’s safety and reliability. At Toyota’s advanced Higashifuji Safety Center, the vehicle has been subjected to extensive crash testing to evaluate a design specifically intended to address frontal, side and rear impacts and to provide excellent protection of vehicle occupants. A high level of collision safety has also been achieved to help protect the fuel cell stack and high-pressure tanks against body deformation.
The high pressure hydrogen tanks have excellent hydrogen permeation prevention performance, strength, and durability. Hydrogen sensors provide warnings and can shut off tank main stop valves. The hydrogen tanks and other hydrogen-related parts are located outside the cabin to ensure that if hydrogen leaks, it will dissipate easily.
The vehicle structure is designed to disperse and absorb impact energy across multiple parts to ensure a high-impact safety performance that protects the Toyota FC Stack and high-pressure hydrogen tanks during frontal, side or rear impacts.
The Toyota FC Stack frame is constructed from a newly-developed thermoplastic carbon fiber-reinforced plastic, which is light, strong, and easily mass-produced. This protects the Toyota FC Stack by absorbing impact shocks from road bumps and other road interference.
In addition to the physical safety measures, the Mirai features a full range of advanced drive assistance and safety systems appropriate for next-generation vehicles.
A Pre-collision System (with millimeter-wave radar) helps prevent collisions or reduce collision damage through alerts and brake control if a high likelihood of collision is detected.
A Lane Departure Alert system uses a camera to detect white or yellow lane markings and alerts the driver when the vehicle is about to deviate from its lane.
Drive-start Control limits sudden starts or sudden acceleration during gear-shift operation.
A Blind Spot Monitor uses radar to detect vehicles in adjacent lanes and helps rear view confirmation when changing lanes.
Design. Like the Prius, Toyota designed the Mirai to be immediately recognizable. A new technique has been employed in the front face design to emphasize the left and right grilles that draw in air for the oxygen supply and for FC system cooling. The novel front face is intended to underscore the vehicle’s individuality.
Toyota says that the side profile evokes the flowing shape of a droplet of water to express the vehicle’s characteristic of drawing in air and emitting water. The roof-side rails and hood appear to pop out of the body to create the impression of a low-to-the-ground vehicle while communicating a futuristic feeling.
The rear of the vehicle presents a bold profile with a trapezoidal shape extending from the license plate garnish to the bottom of the bumper corners and out toward the wheels, while the top of the bumper emphasizes width and expresses a powerfully stable stance. It is also to create an agile and clean impression of air passing through and under the bumper.
The headlights exhibit high-tech and sophisticated luxury through a novel design that presents an ultra-thin profile with an inline arrangement of four LED lights plus visible heat sinks and other optical equipment. The front turn signals and clearance lights are separate from the headlights, contributing to an ultra-thin headlight profile at the same time as merging with the side grilles. This creates an advanced clean design with aerodynamics that improve airflow.
The Mirai comes with 17-inch aluminum wheels that have been made lighter using an engraving process.
Handling stability and quietness. Handling stability and ride comfort are both improved through the location of major parts such as the Toyota FC Stack and high pressure hydrogen tanks centrally under the floor to achieve a low center of gravity and superior front-and-rear weight distribution, as well as the use of a high-rigidity body, which features enhanced rigidity around the rear suspension.
The full under-floor cover and aerodynamically designed clearance lights reduce wind resistance and contribute to improved fuel efficiency and handling stability. Aero fins employed at the side of the rear combination lamps also improve straight-driving stability.
Outstanding quietness is achieved by electric motor drive at all speeds and reduced wind noise, plus full sealing of all body parts, and the use of sound-absorbing and sound-blocking materials optimally arranged around the cabin, including the use of noise-reducing glass for the windshield and all door windows.
Brake support mode makes efficient use of regenerative braking and improves braking performance when the driver wishes to greatly reduce vehicle speed such as when negotiating long downhill sections of road.
Large external power supply system. The Mirai will come with a power supply system with a large capacity of approximately 60 kWh and maximum power supply capability of 9 kW for use during power outages, such as those following natural disasters. (After DC/AC conversion by power supply unit. Power supply capacity varies according to power supply unit conversion efficiency, amount of remaining hydrogen and power consumption.) When a power supply unit is connected, it converts the DC power from the CHAdeMO power socket located inside the trunk to AC power and can power a vehicle-to-home16 system or a vehicle-to-load system. Consumer electronics can also be connected directly and used from the interior accessory socket (AC 100 V, 1,500 W).
Sales and Marketing. In the US, customers will be able to take advantage of Mirai’s $499 per month/36 month lease option, with $3649 due at lease signing, or purchase the vehicle for $57,500. With combined state and federal incentives of $13,000 available to many customers, the purchase price could potentially fall to below $45,000.
The vehicle will be matched by a comprehensive, 360-degree Ownership Experience offering a range of services, including:
24/7 concierge service, with calls answered by a dedicated fuel cell representative;
24/7 enhanced roadside assistance, including towing, battery, flat tire assistance, trip interruption reimbursement, and loaner vehicle;
Three years of Toyota Care maintenance, which covers all recommended factory maintenance, up to 12,000 miles annually;
Eight-year/100,000-mile warranty on fuel cell components;
Entune and three years of complimentary Safety Connect, including hydrogen station map app; and
Complimentary hydrogen fuel for up to three years.
Building a convenient refueling infrastructure. In addition, Toyota continues to support the development of a convenient and reliable hydrogen refueling infrastructure. Research at the University of California Irvine’s Advanced Power and Energy Program (APEP) has found that 68 stations, located at the proper sites, could handle a FCV population of at least 10,000 vehicles. Earlier post. Those stations are on their way to becoming a reality. By the end of 2015, 3 of California’s 9 active hydrogen stations and 17 newly-constructed stations are scheduled to be opened to the general public, with 28 additional stations set to come online by the end of 2016, bringing the near-term total to 48 stations.
Nineteen of those 48 stations will be built by FirstElement Fuels, supported by a $7.3 million loan from Toyota. The company has also announced additional efforts to develop infrastructure in the country’s Northeast region. In 2016, Air Liquide, in collaboration with Toyota, is targeting construction of 12 stations in five states – New York, New Jersey, Massachusetts, Connecticut, and Rhode Island.
The Prius analogy. In both the Japan and US introductions of the Mirai, Toyota executives carefully drew a comparison between the launch of the Mirai and the development and launch of the first Prius. For example:
A quick flashback to the year 2000. I am just starting my new job as the GM in the Los Angeles region, our largest company owned distributor covering Southern California. Our first major task...launch a new Prius, a new hybrid. Fuel is very affordable and there is no market or awareness for this new technology, a gas electric hybrid.
Our dealers were apprehensive but trusted our vision and instincts. We never worked harder to produce 5500 sales in six months in my life. As you know by 2012 we were selling over 235k Prius family sales a year, and it has become the best selling vehicle in California the last two years in a row.
And here we are again, at another turning point in technology. Launching a disruptive technology is a challenge, it’s true… But we did learn a thing or two when we launched Prius 15 years ago… When you launch a new technology, education is key. We learned this with Prius.—Bill Fay, Group Vice President, Toyota Motor Sales and General Manager, Toyota Division
As John pointed out in his introductions of me and Chairman Uchiyamada, we have worked together for many years on this vision of future mobility… involving first the hybrid Prius… and now the fuel cell Mirai. I cannot help but think that to some people, our collaboration—our adventurous road trip—must seem quixotic; idealism without regard for practicality. I, of course, would not agree with that… but at least I know… who is Don Quixote and who is Sancho Panza.
Uchiyamada-san said earlier that Hydrogen, and Hydrogen fuel cell technology will be a societal and economic game changer… and that it will be the fuel for the next century. Frankly speaking, I think I feel a little more optimistic than that. I believe this technology… is going to change our world; and sooner… rather than later. That, in fact, is why we named this car Mirai. We see it as the vehicle that will open the door to future for Toyota.
Of course not everyone agrees. For many years, the use of hydrogen gas to power automobiles has been seen by many smart people as a foolish quest. That point of view is much like opinions 20 years ago of how the Prius hybrid was nothing more than a science project… and economically unfeasible. Sometimes change can happen quickly; a disruption of convention for the better. Other times, change takes persistence. And a long view.
… for any product to revolutionize a market… it must fit neatly and comfortably and conveniently into the everyday lives of the consumer, accomplishing more, without asking for more, of the owner. For all of its technical wizardry, its zero emissions and its bold styling, it needs to be, at the end of the day a regular car. That’s what made Prius a success. We hope that is what makes Mirai a success as well.—Satoshi Ogiso, Managing Officer, Toyota Motor Corporation
Ogiso was one of the original engineers in the Prius program and later the chief engineer for the Prius program.
Prius means “go before,” and for nearly twenty years, Prius paved the way by demonstrating to mainstream buyers that the future in mobility would include electric motors. But “the future” that Prius went before will be the car we will talk about today: the Toyota Mirai hydrogen fuel cell electric vehicle. … The gas-electric hybrid technology in the first Prius blazed a new trail, that many critics said could not be blazed. The hydrogen fuel cell technology in the new Mirai will do the same.—Takeshi Uchiyamada, Chairman of Board, Toyota Motor Corporation
Expectations. Despite the two decades of work preceding Mirai, Toyota views its introduction as only an early step on a much longer road that will entail not just further vehicle development, but also major progress in hydrogen production, infrastructure development, and so on.
Initial delivers may be slow, Toyota noted in Japan, as the vehicles are going to be built meticulously.
We are just at the starting point. Today is not the day of completion and perfection. We will continue our efforts with fresh devotion. Mirai contains two innovations: innovation for mobility, and innovation to realize a hydrogen based society.
Many challenges still remain before these two innovations can be perfected at higher levels. Production, sales and service systems all need to be reinforced for customer to use them with a sense of security. Despite those challenges, Toyota has decided to introduce this vehicle and to take a step forward toward making a difference for the future.—Mitsuhisa Kato, Executive Vice President, Toyota Motor Corp. at the Japan launch of Mirai
The figure that hits me is the storage tank with 5.7% hydrogen by weight.
That exceeds the DOE's just released target for 2020 of 5.5% by weight!
Great job, Toyota.
The 650 Volts used and that it does not need a humidifier are also interesting advances.
Posted by: Davemart | 18 November 2014 at 12:54 AM
The car does not have a practical trunk (half of its space is taken by the hydrogen tank and the battery. It costs 57.5k USD but only does 0 to 60 in 9 sec. If you are lucky enough to find a fuel station you will need to pay more for hydrogen than you pay for equivalent gasoline not to speak of the cost of electricity. For a car that needs to be refueled at a remote public hydrogen tank its range of 300 miles is not nearly enough. Range anxiety will be a real problem here. Of cause Toyota knows it is a hard sell and they only plan to sell a few hundred of them globally in 2015. Basically it is testing program in the public. The auto industry is still a decade away from mass production of hydrogen cars if that ever happens. If the car cannot be made for the same price as a gasser or less (considering its shortcomings relative to gassers and BEVs) it will fail IMO. It cannot do anything better than a gasser so people in general will not pay more for it. At least BEVs can be refueled anywhere (at home 95% of the time). That and lower refueling costs and better trunk space are the main selling points for BEVs over gassers and fuel cell cars.
Posted by: Account Deleted | 18 November 2014 at 12:54 AM
This car has 1865Wh/kg.
After allowing for losses in the fuel stack that comes out to around 1100Wh/kg battery equivalent.
The best batteries in a BEV are in the Tesla, and come out to around 150Wh/kg at the pack level.
Unless that gap can be closed very, very significantly there is a place for fuel cells, but it is a moving target as the energy density of the hydrogen system is increasing also.
Lithium air or something might reduce the place for hydrogen, but we are nowhere remotely near batteries which are in the same ball park in energy density.
Posted by: Davemart | 18 November 2014 at 01:36 AM
Wonder why they made it so slow....
And why couldn't they design better trunk space?
The complexity does make an EV more appealing.
What burns me up is a headline that read - First mass market zero emissions vehicle. Can me guess when this will exceed the 2014 Leaf's sales numbers - 2025?
EVs have a big head start. But at least for Californians who don't have access to home charging, this is a an option between the Leaf and Tesla.
The rest of the country will wait for 2025 but I'm guessing cheaper batteries will come first.
Posted by: David Pilati | 18 November 2014 at 03:12 AM
I agree on the grill and trunk space, and the Hyundai FCEV is far better and more practical in my view.
It is not just California though, Toyota are helping in the build of 12 hydrogen stations in the North East, where cold weather can mean severely restricted range for BEVs in winter, so fuel cells have more going for them.
As you say though, much depends on how fast batteries improve.
Posted by: Davemart | 18 November 2014 at 03:41 AM
Fuel cells have traditionally been aimed at larger cars, basically to fit the stuff in.
Toyota have tried to take it down a size, to something similar to the Prius, and in the process with this generation of technology have significantly compromised the car, aside from its weird styling.
However, getting five years ahead of the game in, for instance, weight reduction in the CF tank is a staggering engineering achievement, and such a rate of progress explains Toyota's enthusiasm for fuel cells compared to the rather delayed progression in energy density in batteries.
Personally I am cheering both on, and hope for as swift as possible progress on all fronts.
Posted by: Davemart | 18 November 2014 at 05:08 AM
Though again, it's another year until a few FC cars MAY actually be sold in California - ONLY with "the rubber hits the road" data, perhaps during the next five years, will the market settle fuel cell cars and use.
Posted by: kelly | 18 November 2014 at 06:16 AM
Though again, it's another year until a few FC cars MAY actually be sold in California - ONLY with "the rubber hits the road" data, perhaps during the next five years, will the market settle fuel cell cars and use.
Posted by: kelly | 18 November 2014 at 06:16 AM
In other news, Toyota has said that fuel cell cars will be more expensive to refuel than gasoline cars for the forseeable future:
They estimate $50 for a full tank of H2 and 300 miles range. Compare this with a Prius, which is cheaper, can refuel at any gas station, has a range of 595 miles, and the gasoline would cost $18 to go 300 miles. With competition like that, the FCV could be a difficult sell, even in Japan.
Posted by: clett | 18 November 2014 at 06:34 AM
They should have made it more visually appealing. It looks like a corolla with flared out fenders. For the price, and inconvenience of finding fueling stations, they really should have done something interesting with the design. Very ugly in my opinion.
Posted by: EStorageGuy | 18 November 2014 at 07:00 AM
There is some amazing technology in this vehicle. Most of the auto companies are planning some type of fuel cell electric vehicle(FCEV). Though there is still some debate about the Hydrogen infrastructure (both the on-board vehicle H2 storage and the necessary refueling process, i.e using compressed H2 gas).
Maybe the technology that GE is investigating concerning Liquid Fuel Cells will change the perspective of FCEV, further blurring the lines between Battery Electric Vehicles and FCEV (reference: http://www.beilstein-journals.org/bjnano/single/articleFullText.htm?publicId=2190-4286-5-153 or here:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4168903/)
Posted by: Account Deleted | 18 November 2014 at 09:10 AM
Indeed, Clett, and there's the WTW efficiency to consider. Which burns less fuel: the Mirai running on H2 from SMR, or a Telsa charged on juice from CCGT?
Posted by: Engineer-Poet | 18 November 2014 at 09:59 AM
The Mirai is better WTW, by a distance, not that there is any real way of sorting out the electricity you get from your wall socket to just tun on CCGT instead of the much more common single cycle, with average natural gas efficiency in the US of 42% before T & D losses.
The Tesla has very low efficiency per mile for an electric car.
Here is ORNL:
(Follow pdf link)
So why am I quoting a link which appears to show the opposite of that which I am arguing, that it is more efficient to burn NG to create electricity for an EV than to use it to make hydrogen for a BEV?
For a start check out fig 14.
The BEV running on electricity from NG is shown as more efficient than the H2 FCEV.
However the Tesla's use a lot more juice than most BEVs, so adjust by however much you feel appropriate for that.
The real kicker though is in table 3, where the efficiency Well to pump of the hypothetical CNG fuel cell with onboard reforming is cited as 85%, whilst the H2 FCEV is only 55%, IOW reforming losses are clearly taken out at that point.
Astoundingly however the efficiency of the CNG fuel cell vehicle at 38.5 mpge where the onboard reforming has still to take place is shown as identical to the H2 FCEV where the reforming has already taken place.
If you put in a more realistic 50-60 mpge there is only one winner.
A FCEV using reformed natural gas is more efficient in its use of the gas than any BEV, let alone the more energy consuming Teslas.
Posted by: Davemart | 18 November 2014 at 10:56 AM
Extended range, very quick refills, better cold weather operation etc may be enough to select this FCEV over an equivalent BEV in many places.
At $42,000 (NET) + free H2 for three (3) years this FCEV may be cheaper than an equivalent fully equipped BMW Series 5?
More H2 stations have to be installed but that will come in due time.
Posted by: HarveyD | 18 November 2014 at 12:33 PM
All those bar graphs are a bit hard to interpret, and I don't see citations for their source calculations.
Figure 14 puts CNG fuel cell vehicle slightly more efficient than the CH4-to-H2 FCEV; certainly the heat of reforming can be put to better use that way. The EV+charger using NG power is given at ~130 gCO2/km, but that's using the lowball CCGT efficiency figure of 51% given in the paper. Modern plants exceed 60%.
This DOE overview shows SMR requiring 137 kBTU of NG, plus 9200 BTU of electricity, to produce and dispense 116 kBTU (1 gge) of H2. If we assume the same 60% efficiency of the electric supply, there's another 15.3 kBTU of gas burned there for a total of 152.3 kBTU input. The pipeline-to-tank efficiency is 76%. You'd need a fuel-cell efficiency of 80% to get the overall efficiency to 60%.
Let's see... 116kBTU of methane @ 60% yields 68.6 kBTU or 20.4 kWh. Running at 380 Wh/mi, that yields 53.6 miles. This is roughly a tie between your 50-60 MPGe FCV and the Tesla, but the Tesla can run on anything that makes electricity while a system running on SMR is tied to NG. Plus, the Tesla Model S can seat 5 adults, 2 kids in jump seats, plus baggage in the frunk. Advantage, Tesla.
Posted by: Engineer-Poet | 18 November 2014 at 01:02 PM
On the lines of comparison to Tesla... 0-60 in 5 sec vs 9 secs
But from a practical standpoint, anyone with a plug at home would have to prefer that to going to a hydrogen station. A 24 hr hydrogen station? A secure location? Close to home?
At least now we can start to have a comparison between EV and FCEV. Looks like for now, the main FCEV advantage is for apartment dwellers. Sure Toyota is subsidizing the cost so if you can get it, it will be cheaper than Tesla - but uglier, slower, smaller, less luxurious. Toyota does have some interesting 120V capability though.
Posted by: David Pilati | 18 November 2014 at 01:17 PM
There is no real way of separating out the CCGT from the grid to use the best theoretical efficiency.
What could be done however is install a SOFC fuel cell in the house or in a small unit, which does run at ~60% efficiency, and the rest can mostly be used for hot water!
So if you run your electric car from a home fuel cell unit, you would be getting pretty good efficiency! ;-)
BTW, being able to seat 5 adults, 2 kids in jump seats, plus baggage in the frunk is not really a sign of efficiency in cars which usually carry 1-2 people!
Posted by: Davemart | 18 November 2014 at 01:23 PM
That's weasel-wording. Just about everything else, save nuclear or wind, would be worse. You can't really use PV because you'd need to size all of your gear for the noon peak.
And I miscalculated the CO2 cost above. To calculate equivalency to the Mirai, the Tesla should be allowed between 8 kg (for 137 kBTU of NG, assuming 100% carbon-free electricity) and 10.5 kg (coal-fired electricity @ 950 gCO2/kWh) for 50-60 miles. 137 kBTU through a CCGT @ 60% will drive the Model S roughly 63 miles.
If you have carbon-free electricity for direct use the Tesla cannot be beat, period. Just the electricity required to reform and pump 1 gge for the Mirai will drive a Model S for 7 miles.
So if you downsized to a vehicle with just 4 seats and a Mirai-sized trunk, you'd have much lower NG consumption and CO2 emissions even if you ran completely on NG.
Posted by: Engineer-Poet | 19 November 2014 at 12:22 PM
It is a real problem that the design of this fuel cell car does not allow for a full size trunk. So what could be done to remedy this? You can't insert a fuel tank in the front of the car as that area is needed as crumble zone for car crashes. There is space at the back seats but then the car would become a two seat car which is unacceptable. The only solution I see is to do like Tesla and make a thick floor in the car and use that for storing five or four long hydrogen cylinders that go from the front wheels to the back wheels. Because of the lower packing efficiency and low volumetric energy density of the hydrogen cylinders the floor would need to be two or three times as thick as the floor in the Tesla. The car would look different than other cars being 10 to 15 inches taller than other cars with the same cabin space but otherwise it will have a full size trunk. The fuel cell could still be packed under the front seats and the battery pack under the back seats. I also think you could store more than 5 kg of hydrogen in such a floor based system. 8 kg would probably increase range to 460 miles and make it more practical as well. It would of cause cost more to use four or five tanks in the floor rater than just two tanks. However, the current design is impractical (limited trunk and not enough range) and an effective show stopper for fuel cell calls so something else has to be done.
Posted by: Account Deleted | 20 November 2014 at 12:18 AM
That thick floor design with gas cylinders could also be used to make a long-range (460 miles) car that run on compressed natural gas. Such a car would cost about 10k USD more than an ordinary gasser solely because of those tanks and even in mass production but NG is also only half the cost or less of diesel or gasoline. If the price of oil ever reaches 200 USD per barrel and stay above that price such a NG car could become popular.
Posted by: Account Deleted | 20 November 2014 at 12:32 AM
Designing a FCV with a trunk is no problem if you reform liquid hydrocarbon fuels into hydrogen on board. Liquid fuel has higher energy density than CNG or H2.
Posted by: SJC | 23 November 2014 at 02:39 PM