Altair's fuel-cell program with MIT
Altair Technologies and the Massachusetts Institute of Technology (MIT) announced in August that the company and university are jointly developing a nanostructured fuel-cell system for direct hydrocarbon conversion. The research program seeks to tackle the major challenges currently present in hydrocarbon-powered fuel cells by combining Altair's materials technology with novel nanostructured anode and cathode catalysts developed by MIT.
The research program will focus on the synthesis and fabrication of enhanced anode and cathode materials and the integration of these structures with the yttria-stabilized zirconia (YSZ) thin film electrolyte for mechanical and thermal stability. It will examine Altair's stable porous structures as support materials for the cathode and anode catalysts.
MIT will deposit its nanostructured anode and cathode catalysts onto Altair's porous supports in conjunction with the YSZ electrolyte thin film. The high porosity and thermal stability of the formed-in-place porous structures should provide superior dispersion of anode and cathode catalysts compared to conventional porous substrates. This would allow MIT to achieve improved hydrocarbon conversions and oxygen adsorption in fuel-cell applications.
The research program to be undertaken at MIT will be directed by Professor Jackie Y. Ying, Associate Professor of Chemical Engineering at MIT.
A month before announcing its joint venture with MIT, Altair announced that it had begun developing ceramic-oxide fuel-cell membranes and reactive catalyst support structures for the development and manufacturing of fuel cells. According to Ken Lyon, President, Altair Technologies, the company's research work in crystalline catalyst bases and surface chemistry control of nanoparticle-sized titanium dioxide led it to the decision to support development teams to research further the technologies.
"We are optimistic that the unique nature of our process for growing crystalline TiO2 from dense films will allow us to overcome the deficiencies normally encountered in high-temperature fuel cells," said Dr. Bruce Sabacky, Altair's principal scientist involved in fuel-cell development. Altair had previously demonstrated its ability to grow porous (greater than 50% void space) interlocked structures of 1-2 µm (40-80 µin) by 8-10 µm (315-400 µin) rutile crystals. This base shows very high structural stability up to around 1100°C (2012°F), according to Sabacky. Surface chemistry control methods will be used to apply catalyst and conductivity components as an integral feature of the support structure. The company is attempting to use this reactive base to support oxygen transfer membrane films using established sol gel techniques.
Jean L. Broge
Volvo's performance concept
Volvo has revealed a high-performance version of the S60 sedan with what it terms a "continuously controlled chassis." The system has been developed in cooperation with damper specialist Ohlins Racing AB.
According to Volvo, the system dubbed Four-C can collect "huge amounts" of information about the way a car moves and can respond instantly by adjusting the damper characteristics. Every alternate millisecond, the system's microprocessor monitors the precise position of each wheel, assesses information such as its degree of grip, and alters the damping characteristics of each individual wheel accordingly.
| 1. Steering sensor 2. Four-C control module 3. Central electronic module (CEM) 4. Dynamic Stability and Traction Control (DSTC) 5. Accelerometer 6. Height sensor |
7. Continuously controlled damper |
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Volvo's Four-C system (Continuously Controlled Chassis Concept) is designed for more responsive automotive handling.
Most information comes from height sensors and body-mounted accelerometers that measure the position and movement of each wheel and the car's body. The car's onboard computer system also supplies information to the dampers to enable the system to foresee events such as a driver braking hard. In such a case, the braking information will reach the dampers before the brake pads touch the discs. Within a few milliseconds, the Four-C microprocessor will have calculated how much the car will want to pitch once the brake pads are actually activated and, using this information, will instantly reset and prepare the dampers to maximize control and roadholding before the body has time to alter its pitch. If ABS is activated, the dampers will set to maximize tire grip.
Hard acceleration or rapid steering inputs will also activate Four-C. The driver can manually select Comfort, Sport, or Advanced Sport modes, although these are system indicators rather than firmly fixed settings, according to Volvo. The Volvo S60 performance concept has DSTC (Dynamic Stability and Traction Control) and electronically managed all-wheel drive that is linked to the car's multiplex system. Volvo is a member of Ford's Premier Automotive Group.
Stuart Birch
Toyota Prius IC/electric hybrid update
Since the launch of the Prius, the world's first volume production internal
combustion (IC) engine/electric hybrid car in October 1997, Toyota Motor Corp.
has sold more than 40,000 units in Japan alone. According to a senior Toyota
executive, the Prius has surpassed the 
world's entire
electric vehicle population. Serious marketing efforts have begun in the U.S.,
and the upright, curious-looking (styled in California), but admirably functional
four-seat sedan has been officially introduced at the Paris Auto Show, with
a fleet of the vehicles driving on the Champs Elysees.
The updated Prius IC/electric hybrid features
body color-keyed bumpers.
The Series-II Prius is faster, cleaner, more frugal, and practical, with a number of significant improvements and refinements. Larger bumpers are now color-keyed to the exterior color. Headlights, rear lights, and wheels have been redesigned. In the interior, by far the most useful feature is a 60/40-split rear seatback that may be individually folded flat to add to the compact car's cargo-carrying versatility. This feature is accomplished with a new, compact nickel/metal-hydride battery pack.
A compact propulsion battery pack
allows the 60/40-split seatback to be
folded flat.
The Series-II battery module is rectangular vs. the Series-I's cylindrical one. Consequently, the 38 modules stack tighter and the battery pack is placed lower behind the rear seat, enabling the seatbacks to fold, connecting to the trunk. Each module is comprised of six 1.2-V cells. The battery pack is cooled by air introduced from the intake on the rear parcel shelf, circulated by an electric cooling fan, and exhausted to the rear of the vehicle.
The 1NZ-FXE dual-overhead-camshaft, four-valves-per-
cylinder, 1.5-L inline
four-cylinder engine specifically designed for the Prius and operating in the
late intake-valve-closing Atkinson-cycle (or Miller-cycle) has been uprated.
It now produces 53 kW (72 hp) at 4500 rpm and 115 N•m (85 lb•ft) at
4200 rpm on a slightly lower compression ratio of 13.0:1 vs. the Series-I's
output of 43 kW (58 hp) at 4000 rpm and 102 N•m (75 lb•ft) at 4000
rpm produced on a 13.5:1 compression ratio. Intake and exhaust valve timings,
air inlet size, and knock-control strategy have been optimized, and various
internal components have been strengthened.
The new nickel/hydride battery module contains six batteries,
with 38 modules making up the battery pack.
The fuel injector now has 12 tiny holes instead of the previous four, promoting finer fuel atomization and contributing to improved fuel consumption and lower emissions. The Prius is the first Toyota car to adopt a 900-cell three-way catalytic converter, which must be one of the most dense substrates in an automotive application. The ceramic monolith has wall thickness less than 0.5 mm (0.02 in) and is coated with palladium and rhodium active substances. The new catalyst volume is reduced from the previous 1.08 to 0.87 L (66 to 53 in3).
Thus equipped, the Prius now qualifies for ULEV classification, both in Japan and the U.S. The recently updated Lexus LS430 also employs the 900-cell catalytic converter. The Japanese version of this full-size luxury sedan, powered by the quad-cam, 32-valve V8 engine, has been certified a SULEV, whose status is matched only by the Sunny (Sentra) compact sedan no mean feat, indeed.
The
propulsion motor/generator has also been upgraded to produce maximum power of
33 kW (44 hp) at 1040-5600 rpm and a peak torque of 350 N•m (225 lb•ft)
at 0-400 rpm, increased from the previous 30 kW (40 hp) and 305 N•m (225
lb•ft), respectively.
The Prius features a more powerfulI
C/electric power unit.
Electric power steering and hydraulically operated brake systems were less than admirable features of the Series-I Prius. Toyota's chassis engineers and electric/electronic specialists must have burnt the midnight oil, for they are much more pleasant now. The brake system incorporates electronically controlled brake distribution feature (EBD) as well as standard ABS.
Jack Yamaguchi
