Improvements relating to the Manufacture of Plates or Electrodes for Primary or Secondary Electric Batteries and to Apparatus therefor.
Year: 1887

page_text: Date of Application, 19th Feb., 1887
Complete Left, 19th Nov., 1887
Complete Accepted, 20th Jan., 1888
PROVISIONAL SPECIFICATION.
Improvements relating to the Manufacture of Plates or Electrodes
for Primary or Secondary Electric Batteries and to Apparatus
therefor.
I, CARL LUDWIG RUDOLPH ERNEST MENGES, of 86 Bali Straat, The Hague, in the
Kingdom of the Netherlands, Electrical Engineer, do hereby declare the nature of this
invention to be as follows:-
My invention relates to primary or secondary batteries of the kind or class wherein
the electrodes are formed with a core which may assist in the generation of electricity,
but which serves chiefly as a support for the active material.
My said invention comprises special forms of these supports or electrodes and a
peculiar manner of producing the same by casting.
These supports can be made of different materials according to circumstances, for
example of lead or of an alloy of lead when compounds of lead or spongy lead are
used for generating the current, or of a non-metallic substance, for instance an india-
rubber compound which is electro-plated with copper, for oxide of copper batteries and
the like.
In electric batteries of this kind or class, the active material frequently separates
from the support. Various forms of supports have been heretofore devised to obviate
this defect, but with some of these forms the desired object is not obtained, whilst
the other forins give rise to inconveniences at least as serious as that which is to be
obviated. The chicf defects or inconveniences of the forms of electrodes heretofore
devised are the following, viz:-
1st. The desired object might be obtained provided there were complate coherence of
the active material, but the form of the electrode does not prevent the falling of the
active material when it loses its coherence, which it generally does sooner or
later.
2nd. The form of the electrode does not permit the free liberation of the gases, and
the area of the surface acted upon by the liquid, that is to say, of the active service is
consequently diminished.

page_text: 3rd. The electrode is not perforated or made in the form of trellis-work, and
consequently it is heavy and does not permit a proper circulation of the liquid.
4th. The area of the metallic or conducting surface is insufficient in proportion to
the thickness of the plate.
5th. The electrode has only continuous metallic parts in a single direction and not
in two directions as in a trellis-work electrode. It is, therefore, not only much less
rigid than an electrode of trellis-work, but it prevents the uniform extension of the
current.
6th. The manufacture of the electrode is difficult and expensive, as it cannot be
made in a single moulded piece but must be composed of several pieces joined
together.
All these inconveniences are obviated in my improved form of electrode.
In the ordinary trellis-work electrodes, the transverse section of the bars or parts
which intersect each other has the form of a very elongated rectangle. My im-
proved electrode, however, has this peculiarity, that the bars or parts which intersect
each other have the form in tranverse section of channels or gutters, that is to say,
they are V-shaped or of similar form; therefore the active material cannot leave the
support either in a downward direction or in a lateral direction, even if the mass should
no longer possess any cohesion at the centre of the plate.
The plate thus formed is very rigid by means of the V-shaped section of the bars.
If the sides of the channels or gutters meet at a right angle, the area of surface of
the electrode is 1.41 times larger than that of an ordinary trellis-work electrode of
the same thickness. Moreover the gases generated can easily escape.
The plate or electrode can be cast in a single piece by means of a peculiar arrange-
ment of the mould. Instead of ensuring the proper position of the two parts of the
mould relatively to each other by means of bolts or bars placed so as to pormit the
movement of one part only in a direction perpendicular to the plane of separation of
the two parts, the mould is arranged in such a manner (by means of inclined bolts or
by other suitable means) that, on opening it, one half or part shall be compelled to
move in the direction of the line of intersection of the sides of the channels or
gutters.
With this arrangement, moulds of sand or of metal can be employed. Moreover,
in order to permit the moulding, it is only necessary that the lines of intersection
shall be parallel; it is not necessary that the channels or gutters shall be parallel.
The shrinkage of the lead and its want of rigidity render it difficult to remove an
ordinary trellis-work plate from a mould of metal or other solid material; too much
inclination must not be given to the sides of the bars or parts which intersect each
other, because that would facilitate the separation of the active material.
With my
improved form, the plate can be removed by pulling at the lower edge, whereby the
entire plate is lifted, because the inclined sides of the channels or gutters act like
wedges. By providing the mould with a device hereinafter described, the removal of
the plates is facilitated. For this purpose, the two parts of the mould are not adjusted
one upon the other by means of bolts, as is ordinarily the case, but by means of
triangular pieces which are fastened to one of the said parts and which engage with
V-shaped pieces secured to the other part. The upper part of the mould can then be
moved along the sides of the triangular pieces in either direction. When this move-
ment is effected in one direction, the cast plate will remain in the lower part of the
mould. By replacing the upper part and effecting the movement in the other direction,
the plate will be detached from the lower part and will remain in the upper part
of the mould. As, however, the plate had already been removed from this part
of the mould, it adheres but slightly thereto and can be easily taken out.
Other devices are provided for effecting the necessary movement of the part or parts
of the mould. The object is to move one of the parts of the mould alternately in
opposite directions, both parts remaining parallel to each other; the devices hereinafter
described are given as examples of the mode of carrying this part of my invention
into effect; I can employ other suitable devices for attaining the desired object.

page_text: As the object is only a relative motion of the two halves or parts of the mould, it
is evident that the two parts can be made movable, and it will then be sufficient to
impart to each of them a motion in one direction.
I employ, for this purpose, levers, screws, wedges or the like. It may be preferable,
in order to diminish the friction, to employ rollers bearing upon each side of the
triangular pieces. In some cases, however, the sides of the triangular pieces are used
as points of support for the levers.
It will be understood that the forming of the active material would be prevented if
each cell of the trellis-work had only a single lower surface in the form of a channel
or gutter, instead of two surfaces. The channels or gutters can then be placed
horizontally. The channels or gutters may have either plane or curved surfaces.
The bars or intersecting parts of the trellis-work are arranged at right angles or at
any other suitable angles to each other; or these two arrangements are combined in
one plate.
Dated thin and day of Santember 1887
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.

page_text: 1 CARL LUDWIG RUDOLPH ERNEST MENGES, of 86 Bali Straat, The Hague, in the
Kingdom of the Netherlands, Electrical Engineer, do hereby declare the nature of
this 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 primary or secondary batteries of the kind or class wherein
the electrodes are formed with a core which may assist in the generation of electricity,
but which serves chiefly as a support for the active material.
My said invention comprises a support of a special form and a peculiar manner of
producing the same by casting.
These supports can be made of different materials according to circumstances, for
example of lead or of an alloy of lead when compounds of lead or spongy lead are
used for generating the current, or also of a non-metallic substance as for example a
composition of india-rubber, covered with a coating of copper by galvanic action, for
batteries of oxide of copper.
It frequently happens in electric batteries of the above described type that the
active material is separated from the support. To obviate the above defect several
forms of supports have been already devised but with some the desired object is not
obtained, whilst the others give rise to inconveniences at least as serious as that which
it is intended to obviate. The principal inconveniences of the forms of electrodes
heretofore devised are due to the following causes.
1st. The desired object might be obtained provided there were complete coherence
of the active material, but this form of the electrode does not prevent the falling of
the active material when it loses its coherence which generally takes place.
2nd. The form of the electrode does not permit the free liberation of the gases,
which reduces the area of the surface acted upon by the liquid, that is to say, of the
active surface.
3rd. The plate is not perforated and consequently it is heavy and does not permit a
proper circulation of the liquid.
4th. The insufficiency of metallic or conducting surface in proportion to the thickness
of the plate.
5th. The electrode has only continuous metallic parts in a single direction and not
in two directions as in a trellis-work-plate. The electrode is, therefore, not only much
less rigid than a trellis work plate, but it also prevents the uniform extension of the
current.

page_text: 6th. The manufacture of the electrode is difficult and expensive, as it cannot be
made in a single moulded piece, the electrode being composed of several pieces joined
together.
All these inconveniences are obviated in the form of electrode that I am about to
describe.
Figure 1 represents in elevation a part of the plate not filled with active material;
presents the form of a trellis. In the ordinary trellis-work-plate the section of the
parts which intersect each other has the form of a very elongated rectangle, but
the new electrode, has this speciality that the parts which intersect each other have the
form of channels or gutters, in such a manner that a section of the plate filled with
active material presents the appearance of Figure 2. The general appearance of the
sections in the directions a b, a c and d e, figure 1, is similar, and it will be seen that
the active material cannot leave the support either in a downward direction or to the
right or to the left even if the mass should no longer possess any cohesion in the
interior of the plate m Figure 2.
The plate is very rigid thanks to its V-shaped section. If the sides of the gutters
meet at a right angle, the surface is 2-141 times larger than that of an ordinary
trellis-work of the same thickness. Moreover it will be seen that the gases generated
can easily escape.
The plate can be cast in a single piece by means of a special arrangement of the
mould. Instead of ensuring the proper position of the two parts of the mould, a and b,
Figure 5 relatively to each other by means of bolts or pins placed so as to permit
the part a to move only in a perpendicular direction to the plane of separation c the
mould is arranged in such a manner (by means of inclined bolts or by other suitable
means) that, on opening it, the half a will be compelled to move in the direction of the
dotted line which is the line of intersection of the sides of the gutters. This line f
Figure 5 is therefore the same as the line, Figure 2, if this Figure represents a
section of the plate according to a b, Figure 1.
With the arrangement described moulds of sand or of metal can be employed. It
will also be seen that in order to permit the moulding, it is sufficient to have all the
lines of intersection parallel, but it is not necessary for the gutters to be
parallel.
The shrinkage of the lead and its want of rigidity are the cause of the difficulty
in removing an ordinary trellis-work plate from a mould of metal or other solid
material, (too much inclination cannot be given to the plates because that would
facilitate the separation of the active material) but with the new form, the plate can be
removed by pulling by the lower edge, whereby the entire plate is lifted, because the
inclined sides of the channels act like wedges. By means of a device added to the
mould the plates can be still more easily removed. For this purpose, the two parts of
the mould are not adjusted one upon the other by means of pins, as is ordinarily the
case, but by means of triangular pieces g Figure 5 fastened to the part 6 of the
mould, and which engage with pieces h secured to the part a. The upper part of the
mould can then be moved along the sides of the triangle g either in the direction of
the arrows d or in the direction of the arrows e. It will be seen that in the first
action the cast plate p will remain in the lower part of the mould. By putting after-
wards the part a in its place, and carrying out the second motion the plate will be
detached from the lower part and will remain in the upper part of the mould. But as
the plate has already been removed from this part of the mould it adheres but slightly
thereto and can be easily taken out.
P
Other devices for effecting the necessary action of the mould are shown in
Figures 6 and 8. As will be seen the object here is to move the two parts of the
mould alternately in opposite directions parallel to each other; the devices described
and illustrated must therefore only be regarded as examples of forms of carrying out
this invention; but I reverse the right to employ also other mechanism for attaining
the desired object.
As the object is only a relative motion of the two halves of the mould, it is evident
that the two parts can be made movable, and it will then be sufficient to impart to

page_text: each part a motion in one direction. An example of an arrangement giving this
result is shown in Figure 9, but arrangements similar to the other figures can also be
employed.
To facilitate the operation of the mould levers, screws, wedges or the like can be
employed. Examples of these kinds of devices are shown in Figures 6, 7, 8 and 9.
The operation by means of the lever i Figure 6 can also be applied to the other devices
illustrated, for example to Figure 5, but it is preferable, owing to the friction to
employ rollers bearing upon each side of the triangular pieces g instead of the pieces h.
The arrangements with levers i, Figure 8, can likewise be applied to Figure 6 or to
Figure 5, and, in the latter case the sides of the triangles g can serve as points of
support for the levers.
It will be easily understood that the falling of the active material would be also
prevented if each cell of the trellis-work had only a single lower surface in the
form of a gutter instead of two surfaces, as shown in Figure 1. The gutters could
then be placed horizontally, as shown in Figure 3, the section being similar to
Figure 2.
In Figure 2 are shown gutters with plane surfaces but they can be curved as shown
for example in Figure 4.
The devices shown in Figures 1 and 3 can also be combined in a single plate.
Having thus particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :-
First. As a support for the active material in primary or secondary electric
batteries. a plate in the form of trellis-work the cells of which have sides
in the shape of gutters so placed that the lines of intersection of the parts of the
trellis-work which cross each other form groups of parallel lines so as to permit the
moulding of the model, or the removal of the casting from the mould in the
direction of these lines.
Second. For the removal of the plates herein before described from a mould of
metal or other material, the employment of mechanism which permits the parts of
the mould to be moved parallel to each other in two different directions, in such a
manner, that during the first movement, one of the parts of the mould is lifted from
the cast plate, whilst, during the second movement the cast plate remains in this par
and is removed from the other part of the mould.
Dated this 18th day of November 1887.