Page 393 - Battery Reference Book

33/8 Nickel batteries
night by coal-burning or nuclear base-load plants. The Bipolar batteries have been under development,
battery could then discharge energy to the network using boiler plate pressure vessels. Design feasibil-
during the day when demand is highest. This would ity has been demonstrated, and the program is now
reduce the need for gas- or oil-burning turbine gen- being directed to design and demonstrate bipolar flight
erators. The successful development of batteries for batteries for high power pulse applications.
either application would reduce dependence on for-
eign sources of oil and also have beneficial effects on
overall fuel costs. 33.4 Nickel-metal hydride secondary
batteries
33.3 Nickel-hydrogen secondary These batteries are under evaluation for application to
electric vehicle traction. The target energy density for
batteries
this application is 80 W hkg-l and 70 W hlkg-' has
Some likely key future developments for nickel- already been achieved in trials. The target power den-
hydrogen batteries could include: (1) increasing the sity is 200 W h/kg-' and the target cycle life is 1000
cycle life for low earth orbit applications to 40000 plus cycles. Other applications include camcorders,
cycles (6.9 years) at modest to deep depths of cellular telephones and computers. This battery may
discharge (40% to 80%); (2) increasing the specific overtake nickel-cadmium types in output and applica-
energy from the state-of-the-art (SOA) 50 W h kg-' to tions by the end of the century.
100 W h kg-' for geosynchronous orbit applications,
and (3) developing a bipolar nickel-hydrogen battery 33.5 Nickel-iron secondary batteries
for high pulse power applications.
lmproving the cycle life will reduce satellite cycle Applications for this type of battery include motive
life costs by reducing the frequency of battery replace- power for industrial trucks, tractors and mine loco-
ment. This may be accomplished by modifying the motives, and also electric vehicles. An energy density
state-of-the-art design to eliminate identified failure of 50 W hlkg-* has been achieved. Electric vehicles
mechanisms and by using 26% rather than 31% (SOA) have achieved a range of 200km on a single charge
KOH electrolyte. and the batteries are currently achieving cycle lives of
As the power required for satellites increases, the 1000-2000 cycles.
fraction of satellite mass occupied by the SOA power
system will also increase, reducing payload mass.
This situation can be altered by increasing the battery 33.6 Sodium-nickel chloride
specific energy. For a given fixed power requirement, secondary batteries
increasing the specific energy will increase the payload
mass or decrease the launch mass. Increased specific The 2.6V sodium-nickel chloride battery is at the
energy could be accomplished by operating at a deeper pilot plant production stage as a possible battery for
depth of discharge and using a thick light-weight nickel electric passenger vehicles and buses. Eagle Picher
electrode substrate which has a high porosity and is are leading workers in this field. Over 1000 charge-
heavily loaded. discharge cycles have already been achieved.