||Why Choose zinc-air
On December 12, 2001, Dr. Fritz R. Kalhammer of Electric
Power Research Institute (EPRI) in Palo Alto, California,
presented his research paper entitled Status of EV Batteries
at the EVAA Electrical Transportation Industry Conference
& Exposition. In his paper, Dr. Kalhammer reviewed
the battery development goals set by United
States Advanced Battery Consortium (USABC) and provides
a clear comparison on all possible candidate batteries
for Electric vehicles.
The chart lists all of the existing battery candidates.
According to Dr. Kalhammer, the actual specific
energy is approximately 1/3 ~ 1/3.5 of the theoretical
specific energy. Therefore, the theoretical specific
energy should be at least 500Wh/kg in order to meet
the requirement of the specific energy set by USABC.
There are only five types of battery, as shown on
this chart, are qualified: Na/S, Li/V2O4.3-5
, Li/S, Al/O2, and Zn/O2.
Candidates of the Battery Used for Electric Vehicles
|| Na/S battery
is a high temperature battery, not suitable for
and Li/S-redox polymers battery are far from mature.
|| Li/S battery
is at early stage of development.
battery is another metal-air battery. Aluminum is
used as anode. Because the recovery of aluminum
from aluminum oxide will consume Electricity 6~7
times more than that of zinc, it is not economically
battery (or zinc air Fuel Cell), however,
is the only type that is a feasible power source
for EVs. According to the final report of ¡°Performance
and Reliability of Batteries for Electric Vehcicles:
A Report of the Battery Technical Advisory Panel¡±,
which was submitted to CARB by the Battery Technical
Advisory Panel on December 11, 1995, the theoretical
specific energy for zinc-air fuel cell is 1085Wh/kg.
The Battery Technical Advisory Panel is co-chaired
by Dr. Fritz.Kalhammer (Electric Power Research
Institute), Dr. Carl Moyer (Acurex Environmental
Corporation), Dr. Akiya Kozawa (Union Carbide Company,
retired), and Dr. Boon Owens (Research International).
Other technical publications set the theoretical
specific energy at 1350Wh/kg¡£
|| Other existing
batteries such as Ni/MH, Ni/Zn, Ni/Cd, LiC6/MnO2
and Pb-acid batteries just cannot meet the USABC¡®s
cell is not Included in the chart. This is because hydrogen
fuel cell technologies are still in the development
stage, meaningful commercialization remains at least
a decade away from being realized. Professor Chan, Chin
Chuan of Hong Kong University, one of the directors
for China¡¯s 863 project Electric Vehicle program, addressed
in National Electric Vehicle Drive Systems Seminar in
late September 2002 in Shanghai, hydrogen-oxygen fuel
cell vehicles will be unavailable until 15 years from
now. As officers of US Department of Energy (DOE) also
stated during their visit to Powerzinc Electric (Shanghai),
Inc. on September 13, 2001, ¡°For stationary use, the
Hydrogen-oxygen Fuel cell will come soon; for powering
vehicles, there is still a long way to go.¡±