BOX 4.2
Status of Advanced Battery Technology
Lead acid batteries were invented in the 19th century and are still the standard battery technology in vehicles today. The GM EV1, a production battery-electric vehicle (BEV), used this battery technology as recently as 1999, and then transitioned to the nickel-metal hydride (NiMH) battery.
The next generation of batteries, based on lithium-ion chemistry, is widely deployed in consumer electronic devices. Of course, the power and energy storage requirements of these devices are much smaller than those of electric vehicles.
Hybrid-electric vehicles (HEVs) require batteries with high power (commonly stated in units of watts per kilogram). Plug-in HEVs (PHEVs) and BEVs require significant energy storage (along with sufficient power). Today’s batteries have an energy storage capacity of 150–200 Wh/kg. A typical vehicle consumes approximately 0.25 kWh per mile in all-electric mode. Typical electric motors that can propel a vehicle require power ranging between 50 and 150 kW.
Chemistries
Table 4.2.1 summarizes the promising advanced battery chemistries and their performance characteristics. Significant amounts of research and development are being devoted to promising new versions of the chemistries of cathode materials, anode materials, and electrolytes, as well as to manufacturing processes.
TABLE 4.2.1 Lithium-ion Battery Cathode Chemistries
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Lithium Cobalt Oxide
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Lithium Manganese Spinel
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Lithium Nickel Manganese Cobalt
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Lithium Iron Phosphate
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Automotive status
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Limited auto applications (due to safety concerns)
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Pilot
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Pilot
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Pilot
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Energy density
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High
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Low
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High
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Moderate
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Power
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Moderate
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High
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Moderate
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High
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Safety
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Poor
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Good
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Poor
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Very good
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Cost
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High
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Low
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High
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High
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Low-temperature performance
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Moderate
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High
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Moderate
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Low
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Life
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Long
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Moderate
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Long
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Long
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Source: Adapted from Alamgir and Sastry, 2008.
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