Fill ‘Er Up With Hydrogen

Japanese car makers ready zero-emission fuel cell vehicles, opening new opportunities for car electronics.

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Japan’s Nihon Keizai Newspaper reported recently that Toyota and Honda would release fuel cell vehicles (FCV) in 2015 at a price of 10 million yen ($98,000) or less. This follows a decline in popularity of electric vehicles due to limited range per charge. FCVs use a generator rather than a battery, which means they need to be filled with hydrogen.

The current cost of an FCV is more than 100 million yen, or $980,000, but if production can be increased to 1,000 vehicles per year, the price will drop by a factor of 10 or more.

The big advantage of FCVs over electric vehicles is range. Toyota, for example, said a single tank of hydrogen would power a car for 830 kilometers, or 516 miles (Reference 1). Currently, electric cars can run about 250 to 300km (155 to 186 miles) on a single charge. A car with a 400km (249 miles) range has been announced and is being tested. Toyota and Honda both got a late start on electric cars, but they are attempting to catch up with the market with the FCV. Nissan also has developed a FCV, and is promoting a low cost fuel cell system (Reference 2).

According to the Nikkei, Honda plans to launch a five-passengers Sedan FCV next year, with a range of 500km per fill-up. The company will produce 5,000 units in five years. Honda has been working with General Motors for the past 13 years to commercialize fuel cells and significantly drop their cost. Toyota, meanwhile, is planning to produce 1,000 FCVs per year initially, with up to 1 million units produced each year by 2020.

One big catch: Fuel-cell vehicles will require hydrogen filling stations. Nikkei reported that from this summer, JX Nippon Oil & Energy and Iwatani International Corporation would begin to develop the hydrogen filling stations. JX Energy is mainly going to serve in the form of establishing the gas station, and is assumed to open 40 locations around Kanto in 2015. The State of California also has plans to set up hydrogen filling stations around the state over the next few years.

FCV are essentially generators. In electric vehicles, in order to increase the torque of the motor and lighten the weight, a thin wire that can handle high voltage is necessary. In electric vehicles, 90 to 100 Lithium ion cells, each about 3.5V, are connected in series. For a FCV to generate the same voltage, 300 to 400 sheets of cells are stacked to produce 600V. Even though current IGBTs can handle these high voltages, further improvements in fast switching and current capacity are expected with silicon carbide; increasing the frequency of the DC-DC converter can reduce the size of inductors and capacitors.

One of the important components that impacts FCV costs is the use of platinum as a catalyst. Platinum is expensive, and the goal is to reduce the use of platinum as much as possible. The Nikkan Kogyo newspaper reported that a team in Kyushu University has developed a technology for depositing platinum particles on the surface of the carbon nanotube (CNT) which has a large surface area. By reducing the particle size of the platinum particles and adjusting the distance between particles the mass activity was increased eight times over conventional approaches.

While the focus on FCV is gaining momentum, there also are improvements under way for gasoline engines. On March 24, Renesas Electronics announced the commercialization of a power management (PM) IC and microcomputer for transmission control and automotive engine control. The IC product is not for a fuel cell vehicle, but for the powertrain device (ECU) required for a finer control in reducing exhaust from conventional gasoline engines. The 40nm ECU has up to 4 Mbytes of built-in flash memory capacity, with operating frequency of 320MHz.

Reference Document

  1. Fuel Cell Vehicle, Toyota homepage
  2. “Expectations for E-PowerTrain as seen from the fuel cell vehicles” Akihiro Iiyama, 1st Green Innovation Symposium (Feb. 26)

The Japanese version of this article is located here.