Improvements in Electrical Secondary Batteries.
Year: 1889

page_text: Date of Application, 10th Dec., 1889-Accepted, 11th Jan., 1890
COMPLETE SPECIFICATION.
Improvements in Electrical Secondary Batteries.
We, JAMES KENT PUMPELLY, residing at 3205, Cottage Grove Avenue, Chicago,
Illinois, United States of America, Electrician, and FRANK DAVID THOMASON,
residing at 539, Sixtieth Street, Chicago, Illinois, United States of America
Lawyer, do hereby declare the nature of our invention and in what manner the
same is to be performed, to be particularly described, and ascertained in the following
statement:-
Heretofore electrical storage batteries have been constructed in such manner that
the electrolitic rapidly evaporates and being in a liquid mass, splashes and spills
out of the cells when placed in a moving vehicle for motive and illuminating
purposes.
Besides this objection the manner of constructing the metal plates of the electrodes
of the battery preparatory to " forming" especially with reference to the application
of the active material (peroxide of lead) thereto, has been such that unnecessary time
is lost in "forming" the plates and considerable difficulty is experienced in retaining
the active material in the same when in practical use.
It is the object of our invention to avoid the objections enumerated above, and
this we are enabled to do by means of certain material and the manipulation thereof
in a manner at once simple and comparatively inexpensive, substantially as herein-
after fully explained and as illustrated in the drawings, in which :--
Figure 1 shows a cross section of an electrical secondary battery with my improve-
ments applied thereto, and,
Figure 2 shows the manner in which we prepare the metal plates of the electrodes,
of the battery.
In the drawings A represents the cell; B represents the pole of the negative
electrode, and the pole of the positive electrode. Each electrode is composed of
a set of metal plates; those of the negative electrodes marked a, a, a, alternating
with those of the positive electrode marked b, b, b, which generally has one more
plate than the negative electrode substantially as shown in the drawings. Each plate
of each electrode has applied to it in some suitable manner the active material c, we
prefer, however, in order to obtain the best results, to adopt and use plates having
perforations in them in which the active material is placed, as shown in figure 1, in
those plates which we have shown in cross section.
Now in constructing these plates we place them with their perforations empty on
same plane surface and then place under them a porous pad d whose surface next to
the plate is plane and even so as to make a temporary bottom for each perforation
of the plate. We then fill the said perforations with dry powdered peroxide of lead in
the condition in which it is usually obtained in the open market, and then securing
said pad to the plate put it in the electric current and charge it. It is of course
preferable to construct the full set of plates it is intended to use in a cell in the
manner above described; connect them in a suitable manner, and put them in their
respective cells in the electrolite, and then turn on the current so as to "form" them
all at once.
This is the most expeditious way of "forming" the plates, and is the way we prefer
when manufacturing for the market.
The constructing of the plates in this manner gives freer and quicker molecular
and chemical action than the old way, which involved the applying of the active
material to the plates in the form of a paste, then drying the same and finally after

page_text: connecting the plates placing them in the electrolite and forming them, and thus we
are enabled to shorten the time required to "form" plates (that is reduce them to
that condition in which they are ready for practical use) from twenty down to about
five hours.
After the plates are formed we remove the pads d and empty the fluid electrolite,
and then fill the cell with cellulose made from fibre D, packing the same between
and around the plates so that it covers the electrodes entirely. We then pour back
into the cell the fluid electrolitic solution, or so much thereof as is necessary to
thoroughly saturate the cellulose D, whereupon we have an electrolite which, because
of its superior capillary properties, offers very little more internal resistance, if indeed
any more, than the electrolitic liquid solution itself.
It effectually prevents the possibility of the plates from "buckling" (short
circuiting), and prevents the dislodgment of the active material. Besides doing this
it equalizes the efficiency of the electrolitic action throughout the cell, whereas
heretofore, where the liquid solution was used, the specific gravity of the acid being
greater it concentrated in the bottom of the cell, and while increasing the efficiency
of action between the lower plates slightly, greatly decreased the efficiency of the
upper plates.
Cellulose made from fibre by the process of its manufacture is perfectly inert both
to the electrical and chemical action of the battery. It therefore lasts indefinitely.
It also retains its moisture for months without replenishing with the solution, and
being of a porous character readily permits the escape of the gases generated by the
action of the battery.
.
Owing to its perfectly inert cbaracter we much prefer, to and in practice do use
pads d made of cellulose made from fibre.
We do not wish to be confined to the use of cellulose made from fibre in the loose
form only, because it is evident that it can be compressed into a compact form and
when saturated with the electrolitic solution answer the purposes of our invention.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :
First An electrolite for electric batteries consisting of cellulose made from fibre
saturated with the electrolitic solution.
Second-The combination with an electric battery of cellulose made from
fibre packed around the electrodes thereof and saturated with the electrolitic
solution.
Third-The combination with an electrical secondary battery and the negative
and positive electrodes thereof consisting of a suitable number of plates alternating
one with the other, of cellulose made from fibre packed between and around said
plates and saturated with the electrolitic solution, as set forth.
Fourth-The combination with the electrodes of an electrical secondary battery,
of metal conductor plated, the active material of which was applied thereto in a dry
powdered state, and held in position by a suitable porous pad while the same was
placed in the solution and subjected to an electric current and formed.
Fifth The method of applying active material to the plates of an electric
secondary battery consisting of applying to said plates the active material in a dry
powdered state and placing against each plate so treated a pad before said plates are
immersed in the electrolitic solution.
Sixth-The method of applying active material to the plates of an electrical
secondary battery consisting of applying to said plates the active material in a dry
powdered condition, and placing against each plate so treated a pad made from cellulose
made from fibre, before said plates are immersed in the electrical solution.
Seventh-The combination with the electrodes of an electrical secondary battery
the plates of which had the active material applied thereto in a dry powdered state

page_text: which was held in place by a porous pad while said plates are being formed, of
cellulose made from fibre packed in said battery and saturated with the electrolitic
fluid as set forth.
Dated this 10th day of December 1889
HUGHES, ELI & HUGHES,
76, Chancery Lane, London, W.C., Agents for the Applicants.