Battery Availability for Near-Term (1998) Electric Vehicles 911914
Battery Requirements were determined for a wide spectrum of electric vehicles ranging from 2-passenger sports cars and microvans to full-size vans with a payload of 500 kg. All the vehicles utilize ac, high voltage (340-360 V) powertrains and have acceleration performance (0-80 km/h in less than 15 seconds) expected to be the norm in 1998 electric vehicles. Battery packs were configured for each of the vehicles using families of sealed lead-acid and nickel-cadmium modules which are either presently available in limited quantities or are being developed by battery companies which market a similar battery technology. It was found that the battery families available encompass the Ah cell sizes required for the various vehicles and that they could be packaged in the space available in each vehicle. The acceleration performance and range of the vehicles were calculated using the SIMPLEV simulation program. The results showed that all the vehicles had the required acceleration characteristics and ranges beween 80-160 km (50-100 miles) with the ranges using nickel-cadmium batteries being 40-60% greater than those using lead-acid batteries.
Significant changes in the design of electric vehicles over the last fifteen years are noted. These changes make the design of the batteries more difficult by increasing the peak power density required from about 60 W/kg to 100-150 W/kg and by reducing the Ah cell size needed from about 150 Ah to 30-70 Ah. Both of these changes in battery specifications increase the difficulty of achieving low $/kWh cost and long cycle life. This is true for both lead-acid and nickel-cadmium batteries.