state-of-the art energy storage systems are typically rated for 8 years of life.

— Expand the acceptable operating temperature range for lithium-ion batteries, currently at 0 to 55°C, by 2017.

— Develop battery technologies that will significantly increase power and energy densities.

— Proposed cost targets:

°    $45/kW and/or $500/kWh for an energy battery by 2017;

°    $40/kW and/or $300/kWh for a power battery by 2020; and

°    By 2016, the cost of the overall battery pack should not exceed the cost of the cells themselves by more than 20 percent.

— Establish an “end-of-life” strategy for advanced batteries and provide the necessary funding related to either the remanufacturing or recycling of batteries by 2017.

Summary of Revised Heavy-Duty Hybrids Goal 4—Hybrid System Optimization, Medium Duty: To develop and demonstrate medium-duty hybrid system technology that can deliver substantial increases in fuel economy, beyond what is available with today’s systems.

— Potential applications for demonstration include medium-duty shuttle buses, vocational trucks, or on/off highway medium-duty work trucks.

— A vehicle demonstration program that provides a platform for developing these medium-duty technologies (similar to the SuperTruck program for heavy-duty technologies) is one potential approach, with development and demonstrations to be completed by 2017.

Summary of Revised Heavy-Duty Hybrids Goal 5—Hybrid System Optimization, Heavy Duty: An overarching goal is to develop and demonstrate heavy-duty hybrid system technology that can deliver substantial increases in fuel economy.

— For urban, heavy start-and-stop driving cycles, a stretch goal of 60 percent (38 percent reduction in fuel consumption) has been identified.

— For regional haul and line-haul applications, the percentage improvements would be more modest, with a stretch goal of 25 percent (20 percent reduction in fuel consumption).

— Additional review and development need to be considered for those vehicles that would possess alternative anti-idling devices that could be provided without additional infrastructure changes.

Summary of Revised Heavy-Duty Hybrids Goal 6—Electrified Power Accessories: Develop robust, durable, efficient electric power accessories for use with medium- and heavy-duty hybrid systems.

— Electrifying accessories such as power steering, air compressors, and air-conditioning compressors can achieve significant reductions in parasitic losses by powering them “on demand.”

— Targeted availability of such improved accessories: 2016.

Comments on New Hybrid Goals

Some of the metrics from the three 2007-2010 goals discussed earlier in this chapter have been carried over to these revised new goals. Specifically,

•   The new revised Goal 1 for electric machines carries over the 15-year design life and cost of no more than $50/kW for the drive-unit system from the 2006 Goal 1.

•   The new revised Goal 3 for energy storage systems carries over the 15-year design life for the energy storage systems. However, the revised Goal 3 specifies a higher cost of $40/kW peak electric power, whereas the 2006 Goal 2 specified a lower cost of no more than $25/kW peak electric power.

•   The new revised Goal 5 for Hybrid System Optimization, Heavy Duty, specifies a stretch goal of 60 percent improvement in fuel economy (38 percent reduction in fuel consumption), which is the same as the 2006 Goal 3.

The committee agrees with the white paper (DOE, 2011) that these goals are indeed “stretch goals.” They appear to be reasonable technical goals, although the 21CTP did not provide the rationale for developing them. The cost and design-life objectives in the 2006 goals had been identified earlier by the 21CTP as necessary for achieving commercially viable heavy-duty hybrid vehicles. Although the 21CTP did not provide specific plans for achieving the six new revised goals, a significant budget is expected to be required through the target dates specified in the goals. Such a significant budget would require a significant increase from the zero budget for heavy-duty hybrid R&D over the past 3 years (FY 2007 to FY 2010).

Finding 4-6. Six new stretch technical goals have been established by the 21CTP for heavy-duty hybrid vehicles. The committee agrees with the 21CTP that these are indeed stretch goals. Specific plans for achieving these new goals, some of which were carried over from the previous three goals that had been set for hybrids, were not provided to the committee. Nor was the rationale provided for these new goals, although they are appropriately focused on fuel consumption reductions, cost reduction, and a 15-year design life for the technologies. They appear to be reasonable technical goals. The cost and design life objectives in the previous goals had been identified earlier by the 21CTP as being necessary for achieving commercially viable heavy-duty hybrid vehicles. It is expected that a significant budget would be required through the target dates specified in the new goals, and a sig-



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