A Plate for Secondary Batteries.
Year: 1889

page_text: Date of Application, 13th Aug., 1889-Accepted, 14th Sept., 1889
COMPLETE SPECIFICATION,
A Plate for Secondary Batteries.
I, WILLIAM PRESCOTT KOOKOGEY, of the City of Brooklyn in the County of
Kings and Stato of New York, United States of America Gentleman do hereby
declare the nature of my invention and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
My invention relates to the plates in a secondary or storage electrical battery; and
it consists of a plate made upon a principle differing from any heretofore known.
My invention consists in general of the combination of a supporting plate of some
solid material which is not destructively acted upon by the acid of the battery, and
which has a low difference of potential with lead (such as wood), such plate being
pierced with openings into which the active material or the material intended to be
made active, is placed; the two plates being held tightly together. The objects
attained by it are, that it lasts very much longer than any plate heretofore known, and
more efficiently, owing to its completely avoiding or greatly diminishing the common
faults which lead to the destruction of the ordinary plate, such as buckling, scaling,
disintegration, reduction of the solid frame of the plate, etc.; and that it is very
much lighter and cheaper, owing to the material used and the ease of manufacture.
In the specification the term "active material" is used to signify the plastic
material held by either the positive or negative plate or electrode; being (after
reduction) peroxide of lead, in one of the plates, and spongy lead in the other.
The positive" plate herein signifies, the active plate, that is, the one holding
the peroxide of lead; and the "negative" plate being the one holding the spongy
lead.
"
At the commencement of the art, the storage battery plates consisted of metallic
lead simply, the active material being formed on their surface by the action of a
charging current. The first improvement upon these consisted of spreading plastic
layers of oxide of lead and litharge, respectively, upon the two lead plates, by which
the forming" of the battery was accomplished more quickly, and a deeper layer of
active material obtained. The chief difficulty with such plates lies in the difficulty
them; the
of keeping the active material (especially in the positive plate), upon
numerous devices to accomplish this heretofore known fall into two classes; (a) the
first class consisting of some change of form in the supporting plates; such as, to
roughen their surface with acid, or mechanically; casting them in the form of a
grid, in the perforations of which, the active material is placed under pressure; or
casting them with inclined pockets in which the active material lies; (b) the second
class consisting of the addition of a cover of some part, to hold the layer of the
active material against the plate by mechanical pressure; such as a porous cover of
tough cloth or a perforated cover of non-conducting, non-corrosive, and non-flexible
material, such as ebonite.
Some of these devices may have been more or less improvements; but the main
difficulty still remains in large measure. The active material on the two plates must
have a certain exposure to the electrolyte, and the plates must be placed very near
together, in order to produce a practical cell. The active material (especially on the
positive plate), still tends to swell and fall away from the lead supporting plate,
causing not only its own loss, but the exposure of more of the lead supporting plate
to the electrolyte, and so leading to the gradual destruction of the plate, and often
causing short-circuiting between the plates. The plate bends or buckles owing to
its character (lead), which buckles under the action of the electric current.
there still remains the tendency of the lead of the plate to be formed into active
material, thus again leading to the destruction of the plate. If the lead supporting
plate is made heavy enough so that it cannot buckle, and will not under the ordinary
And

page_text: action of the battery be injured by reduction of the metallic lead, it then becomes
too heavy and too costly for practical use. If the insulating cover placed over the
layer of active material to keep it on, is made close and thick enough to accomplish
that object, and to prevent buckling, it seriously increases the internal resistance of the
battery by separating the plates; and also decreases the efficiency by retarding the
circulation of the electrolyte.
The invention herein described differs in principle from all that has preceded it.
The essential feature of a storage battery is that the active material a
more or less
plastic substance, must be supported by some solid, and must be held in close contact
with the conductor leading to the terminal, and must also be free to the electrolyte.
In all prior inventions this active material has been supported by the conducting
plate itself. This has been accomplished by means of the molecular attraction, as in
the Plante Plate, or by means of its own adhesive power solely, or by its adhesive
power with the help of projections from the conducting plate, or with the help of a
cover of some sort fastening it to the plate, or by its being placed actually within the
perforations in the plate, or by the combination of two or more of these agencies. In
this invention, however, the conductor is in no way a support. The active material
is supported entirely by an additional plate, which is made of a material not injuriously
affected by the acid or the action of the battery, and the conducting plate is used
simply as a conductor.
In the accompanying drawings in which the same letters indicate the same
parts:-
Fig. 1, is a perspective view of a battery plate, made according to the invention.
Fig. 2, is a perpendicular sectional view of the same on the line a a of Fig. 1.
Fig. 3, is a sectional view with two similar supporting plates, one on each side of
the conducting plate.
The supporting plate a, consists of some material not injuriously acted upon by the
acid, and having a low conducting quality; it has slots or other shaped openings c,
cut entirely through it; in these the active material is designed to lie, in contact with
a thin plate of lead or other conducting material, b. The two plates a and b, being
bolted together by the bolts d, or held in contact in any other appropriate method.
The thickness of the plate a, may be an inch, or any other thickness suitable to the
special use to which the battery is to be put ; and sufficient to prevent buckling of the
plate and the lead plate b, may be quite thin, say, one-eighth of an inch or less,
depending upon circumstances. In Fig. 3, the plate f, is a perforated plate, exactly
similar to the supporting plate a, placed upon the other side of the conducting plate 6,
and also designed to hold active material. The openings of the two plates a and f,
may or may not be opposite each other.
Any material may be used for the supporting plates a and f, which is not corroded
or injuriously acted upon by the acid of the battery; and which has no difference of
potential, or a very low difference of potential with the conducting plate b, such as
hard rubber, chonite, glass etc. The conducting plate b, is preferably made of lead.
The active material may be placed in the openings c, without the use of pressure, and
without skilled labor. If the openings c, are made to present a larger surface to the
lead plate b, than on the outside, it will tend to keep the active material in good
contact with the plate b.
Scaling and disintegration are greatly lessened, if not entirely prevented, by this
invention, inasmuch as the same quantity of active material may be used, as in the
prior forms, with a greatly less surface area exposed to the liquid. Buckling is
entirely overcome by the thickness of the supporting plates a and f, and there is no
danger from reduction of the plate b; the lead of the plate b, which comes opposite
to the wood of the plate a, is entirely protected from reduction, and enough of it will
therefore always remain, to serve the purpose of a conductor; the plate, therefore,
practically is indestructible. With these advantages there is another important one ;
that all the active material in the supporting plates a and f, is available, and it may
all be entirely reduced without injury to the structure of the plate; while in prior
forms only a certain small percentage can be reduced with safety. The result is, that

page_text: for the same amount of active material this plate is many times as efficient as prior
ones. In a battery there is a great saving in weight owing to the comparatively small
quantity of lead needed in the conducting plate. The space occupied for a given
capacity is about the same.
In addition to these general advantages, there are other special advantages in the
use of wood rather than glass, ebonite, etc., for the supporting plate a. They are:
it is light, cheap, easy to manufacture; when saturated with the liquid of the battery
has a certain low conductivity; it has a certain elasticity, thus allowing the blocks
of active material in the perforations c, to swell slightly as they do under the action
of the battery without falling out. The swelling will merely keep them in better.
The best kind of wood, so far as I know now, for this purpose is ash; if treated
with hot paraffine, it will not warp in the liquid of the battery.
The principle of the invention is applicable to the negative as well as the positive
plate, but with greater advantages in the case of the positive plate. The form of
the plate and its perforations may also be varied.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is:
1. In a secondary electric cell, as one of the elements or electrodes thereof, the
combination of active material; a support therefor, which consists of a substance not
injuriously acted upon by the liquid, and has a low difference of potential with lead ;
and a conductor leading to the terminal of the cell, and held in contact with the
active material; substantially as and for the purpose described.
2. A plate for a storage battery consisting of the combination of a supporting plate
having perforations in which the active material lies, such plute being of a material
which is not injuriously acted upon by the liquid, and has a low difference of potential
with lead; and a thin plate of lead fastened to the supporting plate; substantially as
and for the purpose described.
3. A plate for a storage battery consisting of a supporting plate of wood, having
perforations in which the active material lies; and a conducting plate of lead fastened
to such supporting plate; substantially as and for the purpose described.
4. A plate for a storage battery consisting of a wooden plate, a, having perforations c,
to receive the active material, and a thin lead plate b, bolted thereto; substantially as
and for the purpose described.
Dated this Twelfth day of August 1889
CRUIKSHANK & FAIRWEATHER,
62, Saint Vincent Street, Glasgow, Agents.