Page 192 - Lindens Handbook of Batteries

AN INTRODUCTION TO PRIMARY BATTERIES 8.5

popular anode material for primary batteries because of its good electrochemical behavior, high
electrochemical equivalence, compatibility with aqueous electrolytes, reasonably good shelf life,
low cost, and availability. Aluminum is attractive because of its high electrochemical potential
and electrochemical equivalence and availability, but due to passivation and generally limited
electrochemical performance, it has not been developed successfully into a practical active
primary battery system. Magnesium also has attractive electrical properties and low cost and
has been used successfully in an active primary battery, particularly for military applications,
because of its high energy density and good shelf life. Commercial interest has been limited and
use by the U.S. military has terminated. Magnesium also is used as the anode in reserve batteries.
There is an increasing focus on lithium, which has the highest gravimetric energy density and
standard potential of all the metals. The lithium anode battery systems, using a number of dif-
ferent nonaqueous electrolytes in which lithium is stable and different cathode materials, offer
the opportunity for higher energy density and power density in the performance characteristics
of primary systems.

8.2.1 Characteristics of Primary Batteries
Typical characteristics and applications of the different types of primary batteries are summarized
in Table 8.1.

TABLE 8.1 Major Characteristics and Applications of Primary Batteries

System Characteristics Applications
Zinc-carbon (Leclanché), Common, low-cost primary battery; Flashlight, portable radios, toys, novelties,
Zinc/MnO 2 available in a variety of sizes instruments
Magnesium (Mg/MnO ) High-capacity primary battery; long shelf Formerly used for military receiver-
2
life transmitters, and aircraft emergency transmit-
ters (EPIRBs)
Mercury (Zn/HgO) Highest capacity (by volume) of conven- Hearing aids, medical devices (pacemakers),
tional types; flat discharge; good shelf life photography, detectors, military equipment, but
in limited use at present due to environmental
hazard of mercury
Mercad (Cd/HgO) Long shelf life; good low- and high- Special applications requiring operation under
temperature performance; low energy extreme temperature conditions and long life;
density in limited use
Alkaline (Zn/alkaline/MnO ) Most popular general-purpose battery; Most popular primary battery; used in a variety
2
good low-temperature and high-rate of portable battery operated equipment
performance; low cost
Silver/zinc (Zn/Ag O) Highest capacity (by weight) of conven- Hearing aids, photography, electric watches,
2
tional types; flat discharge; good shelf missiles, underwater and space application
life; costly (larger sizes)
Zinc/air (Zn/O ) Highest energy density; low cost; not Special applications, hearing aids, pagers,
2
independent of environmental conditions medical devices, military electronics
Lithium/soluble cathode High energy density; long shelf life; good Wide range of applications requiring high
performance over wide temperature range energy density, long shelf life, e.g., from
utility meters to military electronics
applications
Lithium/solid cathode High energy density; good rate capability Replacement for conventional button and
and low-temperature performance; long cylindrical cell applications, such as digital
shelf life; competitive cost cameras
Lithium/solid electrolyte Extremely long shelf life; low-power Medical electronics
battery