The Dickinson press., 1917-09-29
MOTOR NEWS.
. 9 o o @ 9 @ 9 o 8

Only those who are familiar with
the storage battery industry and have
closely watched the development of
this important part of the motor
car can fully appreciate the signifi-
canoe of the recent announcement by
the Willard Storage Battery Company
of Cleveland, that it has been able to
perfect a threaded rubbed insulation
for starting and lighting batteries.
For years, so it appears, storage
battery makers have been struggling
with the problem of adapting rubber
for insulation in the motor car bat
terry, only to be baked by some one
factor.
Rubber has the durability necessary
for protection of the plates, but this
livery virtue presents an obstacle in
practice; for solid rubber would pre-
vent free circulation of the electrolyte
and decrease the voltage necessary for
reliable starting.
P~erforation of the rubber was re-
sorted to but that raised new diff
%culties, it being impractical to make
perforations which would not allow
bridging" or "treeing" of the active
material from plate to plant and con-
sequent degeneration and ultimate de-
struction Of the battery.
Many devices have been tried out,
such as introducing other separators
in addition to a perforated or solid
rubber insulation, but this again in
creased the size and weight of the
battery beyond the limits which have
been found commercially practical.
The problem was then to use rub
Der without decrease of voltage, with
out increasing battery size, without
holes that would allow the active ma
terial to bridge and without adding 70
the number of parts.
It is interesting to note that in
solving this perplexing problem the
Willard company departed entirely
from the idea of boring holes and re-
sorted to a method as surprisingly m
genious as it is affective. The use of
thousands of tiny threads-196,OO0 to
an insulator-which serve as wicks
and thus permit the circulation of the
electrolyte is something entirely new.
These threads are imbedded in the
rubber and are only as lone as it's in
%sulation is thick-piercing it from
surface to surface. The battery solu-
ton is drawn through the threads Dy
capillary attraction-but there are no
holes through which a contact can be
established from plate to plate by
freeing"
After the idea of accomplishing the
perfection of rubber installations with
the aid of these myriads of threads
was developed, a way had to be de-
'vised to put it into operation. This in
itself was no small task. 1t called
for special machines, and these the
Willard company produced.
Before the Willard company made
general public announcement of the
"Still Better Willard Battery with
Threaded Rubber Insulation" $4,000
of them had been in use over two
years. The kind of service they have
been giving may be judged from the
performance of n Of them in
Georgetown, British Guiana, where
the extreme heat usually limits the
life of wood separators to a year or
less.
The battery went into service Octo-
Der 1, 1915. About August LIST, of
this year, the dealer who sold. the bat
terry wrote to the Willard factory to
say that after twenty-five months of
hard service it was still right on the
job. During all this time it had had
only a few minutes attention a
week-that is, filled, with distilled
water and the specific gravity taken
with a hydrometer. Climatic condi-
tions make frequent filling with water
necessary. After twenty-five months
the car owner, merely as a matter of
precaution, had the battery taken out,
washed with cleaan water and refilled,
and it went back into service appar-
emily good for another long period Of
real work.