Improvements in Secondary-battery Supports or Grids.
Year: 1897

page_text: Date of Application, 5th Jan., 1897-Accepted, 27th Feb., 1897
COMPLETE SPECIFICATION.
Improvements in Secondary-battery Supports or Grids.
I, JOHN, JOSEPH ROONEY, of No. 59 St. John's Place, Brooklyn, County of Kings
State of New York, United States of America, 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 object is to construct an inexpensive support or grid, for the active material
or material to become active, which shall be light and non-oxidizable, and at the same
time possess the properties of porosity, elasticity and insulation in a higher degree
With these objects in
than grids of wood, paper, earthenware or similar material.
view I adopt as the material of which the grid shall be made preferably woollen
felting, and I produce the grid by laying strips of wool-felt in parallel rows lying
in two directions at right angles to each other so that the two sets of rows of strips
form rectangular pockets or holes for the active material. I use an odd number
of layers of strips laid in one direction and an even number of layers of strips laid in
another direction, and make such difference in the thickness of the strips as will
bring the two sets of strips on either face flush with each other. These strips are
fastened together in any suitable manner, but I prefer to fasten them with any
insoluble sealing or cementing composition which is hard when cold but softens under
the influence of heat.
Referring to the accompanying sheet of drawings, which form à part of this
specification,
Figures
and 2 are perspective views of a grid constructed according to my
invention, a metallic conductor being shown in Fig. 2 within one of the rows of
holes.
Fig. 3 is a side view of the construction frame used in preparing the grids, the
frame being high enough to permit the construction of a number of grids at once.
Fig. 4 is a side view of the same construction frame as it would be seen at either
the right or left hand end of the grids shown in Fig. 1 and Fig. 2.
Fig. 5 is a top view of the frame shown in Figs. 3 and 4, the top plate
being broken away at the right where three strips running up and down the sheet
appear.
Fig. 6 is a plan view of a modification of the construction frame of Figs. 3 4 and 5,
the conductors like c of Fig. 2 appearing in the dotted lines.
Fig. 7 is a side view of the modification of the frame shown in Fig. 6, similar in
other respects to Fig. 3.
The construction frame of Figs. 3 4 and 5 is made up of a base plate d provided
with rows of upright chimneys disposed symmetrically throughout the area of the plate
so as to form intersecting channels between the rows of chimneys. These channels
cross each other at right angles and form the guides in which are laid the strips of
material to be fastened together. At the end of each row of chimneys along all four
sides of the frame are set upright sheets of about the width of that side of the end of
the chimney turned toward these sheets. These upright sheets are provided with
ribs r to stiffen them. The sheets and chimneys are perforated to allow circulation
of hot air used. This base plate d is provided with downwardly extending ribs,²
forming feet. Upon the base plate may be set a false bottom d' provided with
handles forming a sort of a tray upon which the grids are built up and by which

page_text: they can be lifted off from the construction frame. This tray, of course, is provided
with rectangular perforations which fit over the chimneys. It may, of course, be
made up of a few slats, but its use is not important. The frame is provided with
three ribs, upon which pressure can be brought to bear.
Instead of the chimneys above referred to, I may substitute mere upright posts as
shown in Figs. 6 and 7. There is a post at each corner of each rectangle of Fig. 6
and posts around the outer edges, one of which lies opposite each of the posts at
an outside corner of an outside rectangle of the base plate. The base plate is
marked in these figures d2 and the upright posts u. The base plate d is provided
with foot-ribs similar to those marked in Fig. 3, and in Fig. 7 are shown
strips of felting marked 11 21 31 a and b, which are similar to parts shown in
Figs. 1 to 5.
I build up the grid by laying a row of strips as 1, of wool-felt along each of the
channels lying in one direction, then placing upon each of these strips a sealing-wax
strip w made up as hereafter explained, then laving a row of strips, as a, through cross
channels with a sealing-wax strip w upon each of these strips as before. This method
of building up is continued by laying strips of wool-felt and wax, 2 w 63, until the
desired thickness is obtained, there being as is shown in Figs. 1. 2 3 and 4 an odd
number of layers of strips of wool-felting in one direction and an even number in the
other direction, and the strips in the two directions alternating.
It will be seen by reference to Fig. 1 that for each three strips laid in one direction
which may be called longitudinal strips, I use two strips which may be called
cross strips, laid across these longitudinal strips. Wax is placed between the
intermediate longitudinal strip and each of the outside longitudinal strips, and between
the two cross strips. Having built up one set of layers to form one grid in this way,
I may, as shown in Figs. 3 and 4, begin immediately a set of layers to form another
grid by duplicating the last set of layers of one grid without putting any sealing-wax
between these duplicate layers, then treating the second of these duplicate strips as
the first row of the new set of strips, I build up the second grid in the manner
already explained. Figure 3 shows strips disposed to form two grids, and it is clear
that the frame will hold the layers for a third grid. When the strips have all been
properly disposed, and the frame is as full as is desired, heat is applied through
the chimneys. These chimneys may be sealed at the top and hot air forced in
at the bottom. This air will be forced out through the perforations in the side of
the chimneys, and into the mass of wool-felting and sealing-wax, thus melting the
The top t is brought down on the pile of strips, and pressure is applied so as to
force the strips into close contact. The heat is then withdrawn and the mass held
under pressure until the sealing-wax thoroughly hardens, when the pressure is
relieved, the top is taken off and the false bottom is lifted out with the grids lying
upon it.
wax.
I prefer to apply the sealing-wax by taking unsized cotton-tape and passing it
through a bath of molten sealing-wax. This forms a thoroughly manageable strip of
sealing-wax which can be used to stick the strips of wool-felt together. If the
sealing-wax be laid on the tape quite thick it gives quite a stiffness to the grid,
especially if a number of the layers of the wax are used. Instead of putting these
strips into the frame by hand, I may feed them in from a machine.
By painting or coating one side of the felt sheet with the melted sealing composition,
and then cutting it up into strips of suitable lengths, the use of the prepared tape may
be dispensed with and the operation of building up the grids quickened. The strips
of wool-felt are then laid in the form and under the influence of heat and pressure
the layers are firmly cemented together.
4
As shown in Fig. 1, the ends of the longitudinal layers may extend out in one
direction to form foot-rests for the grid, and as is shown in Fig. 2, I may place between
some of the layers preferably the cross-layers, conductors c which are disposed so as
to lie along the middle of the holes or pockets formed in the grid. Instead of this
method of getting the metallic contact, I may wrap metallic strips around the outside
of the grid, these strips lying along each layer of perforations, but both the outside

page_text: and intermediate contact pieces may be used together. But I prefer the first method
above described, because where the conductors are laid between strips so that one
conductor shall lie in each row of holes or pockets and midway between the faces of
the grid, these conductors are never exposed to the solution except through the active
material. Therefore, in charging, there is no shunting of the current or any part of
it, but the entire current must traverse the pellets of active material. I make up my
plate by filling the pockets or holes with active material or material to become active,
and I may so construct the plate that it shall be bi-polar or uni-polar as is preferred.
It is obvious that I may make the grids in large sections and then cut them up to
suit. It is unnecessary that the work be done by hand, but it is not material whether
the grid is handmade or done by machinery. The grid can, of course, be made up of
strips of wool laid in one direction and of asbestos laid in the other direction, or with
the strips of wool and asbestos otherwise combined to form the grid, and the strips
themselves can be made of mixed wool and asbestos.
In carrying out my invention I do not limit myself to the precise details here
shown, and may adopt instead other methods of securing and holding the active
material in place such as are shown in my British Patent No. 20431, dated the
29th of October, 1895.
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. A grid for a secondary battery plate made up of layers of strips of wool-felt
laid together in sets of rows which cross each other so as to form pockets or holes
between the rows, substantially as described.
2. A grid for a secondary battery plate made up of layers of strips of wool-felt,
the strips forming the different layers being fastened together by sealing-wax; the
strips being laid in sets of rows which cross each other, so as to form pockets or
described.
holes between the rows of strips, substantially as
3. A grid for a secondary battery plate made up of layers of strips of insulating
rows which cross each other,
and porous material, the strips being disposed in
forming rows of holes or pockets between the rows of strips and conductors laid
between the strips, one along each row of holes or pockets and midway between
the faces of the grid, substantially described.