17 November 2008
Alkaline storage battery
The nickel-iron alkaline battery was a lightweight,
inexpensive portable power source for vehicles with electric motors.
The people behind the invention:
Thomas Alva Edison (1847-1931), American chemist, inventor,
Henry Ford (1863-1947), American inventor and industrialist
Charles F. Kettering (1876-1958), American engineer and
A Three-Way Race
The earliest automobiles were little more than pairs of bicycles
harnessed together within a rigid frame, and there was little agreement
at first regarding the best power source for such contraptions.
The steam engine, which was well established for railroad and ship
transportation, required an external combustion area and a boiler.
Internal combustion engines required hand cranking, which could
cause injury if the motor backfired. Electric motors were attractive
because they did not require the burning of fuel, but they required
batteries that could store a considerable amount of energy and
could be repeatedly recharged. Ninety percent of the motorcabs in
use in New York City in 1899 were electrically powered.
The first practical storage battery, which was invented by the
French physicist Gaston Planté in 1859, employed electrodes (conductors
that bring electricity into and out of a conducting medium)
of lead and lead oxide and a sulfuric acid electrolyte (a solution
that conducts electricity). In somewhat improved form, this
remained the only practical rechargeable battery at the beginning
of the twentieth century. Edison considered the lead acid cell (battery)
unsuitable as a power source for electric vehicles because using
lead, one of the densest metals known, resulted in a heavy
battery that added substantially to the power requirements of a
motorcar. In addition, the use of an acid electrolyte required that
the battery container be either nonmetallic or coated with a nonmetal
and thus less dependable than a steel container.
The Edison Battery
In 1900, Edison began experiments aimed at developing a rechargeable
battery with inexpensive and lightweight metal electrodes and an
alkaline electrolyte so that a metal container could be used. He had already
been involved in manufacturing the nonrechargeable battery
known as the Lalande cell, which had zinc and copper oxide electrodes
and a highly alkaline sodium hydroxide electrolyte. Zinc electrodes
could not be used in a rechargeable cell because the zinc would
dissolve in the electrolyte. The copper electrode also turned out to be
unsatisfactory. After much further experimentation, Edison settled
on the nickel-iron system for his new storage battery. In this system,
the power-producing reaction involved the conversion of nickel oxide
to nickel hydroxide together with the oxidation of iron metal to
iron oxide, with both materials in contact with a potassium hydroxide
solution. When the battery was recharged, the nickel hydroxide
was converted into oxide and the iron oxide was converted back to
the pure metal. Although the basic ingredients of the Edison cell were
inexpensive, they could not readily be obtained in adequate purity
for battery use.
Edison set up a new chemical works to prepare the needed materials.
He purchased impure nickel alloy, which was then dissolved
in acid, purified, and converted to the hydroxide. He prepared
pure iron powder by using a multiple-step process. For use
in the battery, the reactant powders had to be packed in pockets
made of nickel-plated steel that had been perforated to al-
low the iron and nickel powders to come into contact with the electrolyte.
Because the nickel compounds were poor electrical conductors,
a flaky type of graphite was mixed with the nickel hydroxide at
Sales of the new Edison storage battery began in 1904, but within
six months it became apparent that the battery was subject to losses
in power and a variety of other defects. Edison took the battery off
the market in 1905 and offered full-price refunds for the defective
batteries. Not a man to abandon an invention, however, he spent the
next five years examining the failed batteries and refining his design.
He discovered that the repeated charging and discharging of
the battery caused a shift in the distribution of the graphite in the
nickel hydroxide electrode. By using a different type of graphite, he
was able to eliminate this problem and produce a very dependable
The Ford Motor Company, founded by Henry Ford, a former
Edison employee, began the large-scale production of gasolinepowered
automobiles in 1903 and introduced the inexpensive, easyto-
drive Model T in 1908. The introduction of the improved Edison
battery in 1910 gave a boost to electric car manufacturers, but their
new position in the market would be short-lived. In 1911, Charles
Kettering invented an electric starter for gasoline-powered vehicles
that eliminated the need for troublesome and risky hand cranking.
By 1915, this device was available on all gasoline-powered automobiles,
and public interest in electrically powered cars rapidly diminished.
Although the Kettering starter required a battery, it required
much less capacity than an electric motor would have and was almost
ideally suited to the six-volt lead-acid battery.
Edison lost the race to produce an electrical power source that
would meet the needs of automotive transportation. Instead, the internal
combustion engine developed by Henry Ford became the standard.
Interest in electrically powered transportation diminished as
immense reserves of crude oil, from which gasoline could be obtained,
were discovered first in the southwestern United States and
then on the Arabian peninsula. Nevertheless, the Edison cell found
a variety of uses and has been manufactured continuously throughout
most of the twentieth century much as Edison designed it.
Electrically powered trucks proved to be well suited for local deliveries,
and some department stores maintained fleets of such
trucks into the mid-1920’s. Electrical power is still preferable to internal
combustion for indoor use, where exhaust fumes are a significant
problem, so forklifts in factories and passenger transport vehi-
cles at airports still make use of the Edison-type power source. The
Edison battery also continues to be used in mines, in railway signals,
in some communications equipment, and as a highly reliable
source of standby emergency power.
Thomas Alva Edison
Thomas Alva Edison (1847-1931) was America’s most famous
and prolific inventor. His astonishing success story, rising
from a home-schooled child who worked as a newsboy to
a leader in American industry, was celebrated in children’s
books, biographies, and movies. Corporations still bear his
name, and his inventions and improvements of others’ inventions—
such as the light bulb, phonograph, and motion picture—
shaped the way Americans live, work, and entertain
themselves. The U.S. Patent Office issued Edison 1,093 patents
during his lifetime, the most granted to one person.
Hailed as a genius, Edison himself emphasized the value of
plain determination. Genius is one percent inspiration and 99
percent perspiration, he insisted. He also understood the value
of working with others. In fact, one of his greatest contributions
to American technology involved organized research. At age
twenty-three he sold the rights to his first major invention,
an improved ticker-tape machine for Wall Street brokers, for
$40,000. He invested the money in building an industrial research
laboratory, the first ever. It led to his large facilities at
Menlo Park, New Jersey, and, later, labs in other locations. At
times as many as one hundred people worked for him, some of
whom, such as Nikola Tesla and Reginald Fessenden, became
celebrated inventors in their own right.
At his labs Edison not only developed electrical items, such
as the light bulb and storage battery; he also produced an efficient
mimeograph and worked on innovations in metallurgy,
organic chemistry, photography and motion pictures, and phonography.
The phonograph, he once said, was his favorite invention.
Edison never stopped working. He was still receiving patents
the year he died.