Page 448 - Battery Reference Book

Other power sources for vehicle propulsion 43/7

Figure 43.5 Ten-cell lithium aluminium alloy-iron sulphide ten-cell module for vehicle propulsion (Courtesy of Eagle Picher)

Westinghouse are developing a 36 V electric vehicle In the 1980s both Gould and Exxon curtailed their
lithium-aluminium-iron sulphide battery which has a work on this development and transferred it to other
specific energy of 112 W h/kg on the basis of cell mass companies-Johnson Controls Inc. (USA), Meiden-
and 98 W h/kg-' on the basis of battery module weight sha Electric Co. (Japan) and SEA GmbH (Austria).
including heat dissipating system. No commercial battery has yet emerged from these
This gives the battery a 100-mile range under stan- activities.
dard electric vehicle test profiles. The battery has a
cyclic life of 120 cycles. 43.2.6 Lithium solid state batteries
Westinghouse batteries for vehicle production in
the 2.5 to 7.5 W h range are near to commercial pro- This type of battery has been considered for vehicle
duction. propulsion and scaling-up programmes hopefully lead-
In general the technology of lithium-aluminium- ing up to demonstration units are underway at Harwell
iron sulphide cells for electric vehicle applications is Atomic Energy Establishment UK.
now estalished but needs evolutionary improvements
to become fully commercial. 43.2.7 Sodium sulphur battery
A target energy density is 150 W h kg-'.
This battery has not yet been developed to the com-
43.2.4 Aluminium-air batteries mercial stage, despite intensive efforts by several
companies.
It has been shown that an aluminium-air battery Calculations show that battery specific energies of
could power a compact car provided 14kg of fresh around 100-150 W h/kg-' and peak power capabilities
aluminium and 23 litres of water could be installed of 120 Wkg-' are needed for traffic compatible elec-
every 400km and 41 kg of hydroxide sludge disposed tric delivery vans with worthwhile ranges, with even
of. Clearly, this is a very speculative project. Alcan, more demanding requirements for smaller vehicles
US has carried out some work on the development of such as automobiles.
this type of battery. To put this into perspective, specific energies cur-
The latest development of the Alcan aluminium air rently being achieved by lead-acid, nickel-iron and
battery is a hybrid unit comprising eight lead-acid iron-air batteries are respectively 25-45, 50 and
batteries and a bank of aluminium-air batteries to 20 W h kg-' .
power a small hatchback vehicle. The target is a range Several manufacturers are attempting to develop
of 105 miles at 30mph. Eltech Corporation US are sodium-sulphur batteries for electric vehicle applica-
developing a 100 V aluminium-air traction battery. tions. Some of the advantages of sodium-sulphur bat-
teries are: low rising resistance during cycling (by
43.2.5 Zinc Bromine batteries control of impurity levels), no memory effects, no sec-
ondary reactions, unlimited charge retention, amp hour
Exxon Research and Engineering Co., and Gould Inc., capacity independent discharge rate and high shelf life.
both of the USA have done extensive research and Chloride Silent Power are developing a 960 cell bat-
development and engineering work, funded by the US tery which has been tested at Ford Motor Company.
Department of Energy and the Electric Power Research The delivery van (GM GriHon van) constructed by
Institute, on the development of a zinc-bromine battery Chloride Silent Power has a range of 163 miles at
for electric vehicle use. 35 mph or 120 miles at 50 mph. Chloride Silent Power