Toyota Outlines Technology Strategy for Alternative Powertrains: Right Vehicle, Right Place, Right Time
|Toyota says it is pursuing all of these energy and powertrain pathways. The brick walls in the diagram represent barriers to be overcome. Click to enlarge.|
In a presentation at the recent Toyota Environmental Forum held in June in Japan, Masatami Takimoto, Executive Vice President, outlined the company’s technology strategy for meeting the needs of a “sustainable mobility society”. (Earlier post.)
Hybrid—and plug-in hybrid—technology is core to Toyota’s plans, but Takimoto described a range of efforts across conventional powertrain development, alternative fuels, biofuels, electricity, and hydrogen pathways that Toyota believes will be required.
Because of the many obstacles that must be overcome because of alternative energy source, more than one type of vehicle will have to be used to obtain the sustainable mobility society, and because in each region, the energy situation is different.
Toyota believes it is important to provide different vehicles with different powertrains capable of using the remaining precious oil carefully, and using alternative energy sources. Based on the energy market situation from region to region, our goal is to achieve CO2 emissions reduction and cleaner atmosphere with the right vehicle, in the right place, at the right time.
Therefore, as described in the dotted line in the graph [see above], we plan to combine hybrid and plug-in hybrid technology with various types of different powertrains to help solve the environmental and energy issues we face and to achieve a sustainable mobility society.—Masatami Takimoto
Takimoto discussed five broad categories of development work:
- Further development of gasoline- and diesel-fueled combustion engines;
- Hybrids and plug-in hybrids;
- Alternative fuels, including synthetics and biofuels;
- Electric vehicles; and
- Hydrogen fuel cell vehicles.
|Toyota’s directions in powertrain development. Click to enlarge.|
Gasoline and diesel combustion engines.Gasoline and diesel will remain the mainstay for the time being, Takimoto said. Because peak oil is “undoubtedly getting closer”, it is important to use the remaining oil carefully. Toyota is trying to improve fuel economy by making smaller, lighter-weight vehicles and improving powertrain efficiency.
The company believes that it will be necessary to improve vehicle weight and size reductions in the future, and to be applied in all its vehicles.
Toyota is introducing new 1.3- and 2.5-liter gasoline engines this year. The 1.3-liter engines applied in upcoming vehicles will have a new stop-start system. By the end of 2010 TMC will complete the transition to a new series of highly efficient engines and transmissions.
Important directions for future engine development includes downsizing through the use of direct injection and supercharging; work on homogeneous charge compression ignition, and work on a variable compression ratio mechanism.
Hybrids and plug-in hybrids. Toyota’s goal is to have hybrid models for all its vehicle series by 2020. Achieving that will require ongoing reduction in the size and weight of the component technology, Takimoto said.
With its most recent electric motor (in the LS600h), Toyota is delivering output density of 3x that of the current generation Prius. Likewise, the inverter output density ratio has also increased 3x from the current Prius generation.
Toyota is also increasing the output density of its NiMH battery packs. Although Toyota has Li-ion work under development, NiMH will remain a major chemistry for its hybrids, Takimoto said. Toyota plans differentiated usage of NiMH and Li-ion, with the lithium-ion packs heading initially to plug-in hybrid vehicles and to small, short-distance electric vehicles. Future, larger EVs will be based on a next-generation battery chemistry.
The plug-in hybrid, Takimoto said, “is the most realistic option for utilizing electricity [as an alternative fuel] at the present time.”
He re-affirmed that Toyota will introduce a Li-ion-based plug-in by 2010 geared toward. Toyota, which is also researching photovoltaic power generation and biofuels, suggests that supplying PV electricity to a biofuel plug-in is a means of completely eliminating CO2 emissions.
Alternative fuels. With a diminishing conventional oil supply, Toyota sees the coming shift of production to nonconventional crude such as deep sea and oil sands as increasing and raising cost.
From a medium-term perspective, automobiles will have to use gas fuels such as natural gas, or synthetic fuels made from coal or biomass. However, with gas fuels, the limited cruising distance proves difficult. With synthetic fuels, we need low cost and reduced CO2 emissions during fuel synthesis. Therefore, from the viewpoint of reducing CO2 emissions, it will be necessary to utilize biofuels such as bioethanol and biodiesel.—Masatami Takimoto
Toyota is conducting research on the conversion of wood chips and other biomass to ethanol, and is also partnering with Nippon Oil on researching Bio Hydrofined Diesel (BHD)—a renewable diesel produced by the hydrotreatment of vegetable oils or fats.
Electricity. Despite the attraction of electricity as a power source for transportation, a number of issues remain, Takimoto said, including the energy density of the batteries; infrastructure issues (such as recharging facilities); and the greenhouse gas output from thermal power generation.
|Toyota is targeting “revolutionary” energy storage systems. Click to enlarge.|
Although Toyota plans to accelerate its development of small electric commuting vehicles, it is focusing on the development of next-generation batteries with greater energy densities than offered by current lithium-ion systems before ordinary vehicles can become EVs. The company is establishing a battery research department “to accelerate R&D on these new revolutionary batteries”. Examples of such batteries adduced in the presentation include solid-state lithium, and metal-air batteries, with the potential for a “Sakichi” battery.
Sakichi Toyoda, the inventor of Japan’s first power loom and called by some the father of the Japanese industrial revolution, founded in 1926 the Toyoda Automatic Loom Works and what would eventually become the Toyota Group. A “Sakichi” battery would represent breakthrough innovation that would re-define an industry.
Hydrogen fuel cells. Toyota continues to develop its fuel cell vehicles, most recently introducing its latest version of the FCHV. (Earlier post.)
On top of the challenges of the vehicle technology, the hydrogen related infrastructure and CO2 emissions reduction needs to be established in related areas. We shall aggressively cooperate with related parties.