Year: 1888

page_text: Date of Application, 9th May, 1888
Complete Specification Left, 11th Mar., 1889
Complete Specification Accepted, 13th Apr., 1889
I, MORITZ IMMISCH, of 119 Torriano Avenue, Camden Town, London, in. the
County of Middlesex, Electrician, do hereby declare the nature of this invention to
be as follows:―
The object of this invention is to do away with certain imperfections appertaining
to storage batteries in which peroxide of lead is used as the active material. One
great objection is the liability of the positive plates to get distorted and by doing
so producing false contacts and short circuits in the cell, and moreover causing the
active material to break away from the conductor. This in my opinion is owing to the
peroxide of lead being interspersed with conducting material, which latter cannot follow
the expansions and contractions attending irregular and copious discharges of current
such as take place when accumulators are used for tramcar work for instance.
.
Other inventors have already recognized the fact that the interspersion of the
conductor with the active material is unnecessary, and have used plates of solid
peroxide of lead. Inasmuch however that with such irregular and sometimes
excessive discharges as already mentioned, a solid plate is very liable to break, and
as the conductor although not inside the plate is nevertheless permanently and
securely connected to the peroxide plate, such a breakage is fatal to the efficient
working of the cell.
I obviate this difficulty by using solid peroxide strips or bars arranged transversely
in relation to the conductors, which are brought into contact with both sides of
the bars forming the positive plates, such conductors being in the shape of combs
made of lead, compounds of lead, or other non-oxidizable metal.
The prongs of the combs are not permanently connected to the bars of peroxide of
lead forming the positive plate, but only rest upon and are kept in contact therewith
by pressure as hereinafter described.
The negative plates are supplied with similar conductors on both sides. The
positive and negative plates with their conductors are then placed side by side and
separated by a sheet of non-conducting material which is perforated. The perforations
and the conductors are so arranged that the prongs of the two plates are opposite each

page_text: other and pass through the centre of a row of perforations. By these means the con-
ductors are brought into close proximity to each other, thus lessening the internal
resistance of the cell, while at the same time the plates themselves are separated by
comparatively wide spaces, thus affording room for a large volume of liquid between
them. These features form an important improvement over the cells as hitherto
constructed, inasmuch as in the latter the conductors forming part of the plates, it
was necessary to place the plates themselves near together in order to diminish the
internal resistance, while at the same time lessening the space for the fluid between
the plates.
Experience has shown that the surfaces of the liquid layer between the plates have
to be a certain distance apart in order to get good results. It will be seen that I get
the requisite distance without increasing the internal resistance, by means of the close
proximity of the conductors.
The prongs are placed upright in order to facilitate the escape of gases.
When a sufficient number of plates have been built up as described, the pile of
plates is furnished with a strong plate of suitable material at each end. The whole is
then submitted to pressure and while in that state the ends of all the negative con-
ductors are connected together and secured to the outer surface of one of the end
plates to form a terminal, while those of the positive plates are similarly connected
and led to the other end plate to form the other terminal. The pile in this com-
pressed state is then inserted into a suitable box, through two opposite sides of
which at points in line with the centre of the end plates holes are formed and
fitted with screwed bushes, made of lead or other non-oxidizable material. Pressure
screws work through the bushes and bear upon the terminals on the end plates, such
screws serving to maintain the pressure on the pile of plates and also form the
external terminals. The pressure is rendered yielding by interposing elastic washers
between the flanges of the bushes and the inner surfaces of the box. This pressure,
as all the surfaces are flat and the conductors straight and equal in thickness, is
sufficient in itself to keep everything in position, while allowing the necessary play
when any expansions or contractions take place, but for extra security strips of lead
or other suitable material may be placed round the edges of the spaces occupied by
the peroxide bars, thus forming a kind of enclosing frame for them.
The elastic washers with which the bushes are provided further serve to render
the bushes water-tight.
By causing the terminals to pass through the water-tight joints in the sides of the
box, I am enabled to cover the whole with liquid without leaving any terminals
exposed to the corrosive influence of the nascent oxygen evolved, which is a great
drawback in the form of accumulators at present in use.
Dated to 1
1000

page_text: COMPLETE SPECIFICATION.
Improvements in Storage Batteries.
I, MORITZ IMMISCH, of 119 Torriano Avenue, Camden Town, London, in the
County of Middlesex, Electrician, 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 :-
The object of this invention is to do away with certain imperfections appertaining
to storage batteries in which peroxide of lead is used as the active material. One
great objection is the liability of the positive plates to get distorted and by doing so
producing false contacts and short circuits in the cell, and moreover causing the active
material to break away from the conductor. This in my opinion is owing to the
peroxide of lead being interspersed with conducting material, which latter cannot
follow the expansions and contractions attending irregular and copious discharges
of current, such as take place when accumulators are used for tramcar work for
instance.
Other inventors have already recognized the fact that the interspersion of the con-
ductor with the active material is unnecessary, and have used plates made of solid
peroxide of lead, generally perforated in the centre with the conductor firmly secured
in the middle of the plate. This mode of connection, however, often causes the plates
to break with excessive and irregular discharges, and does not offer sufficient contact
between the active material and the conductor.
A further difficulty consists in the injurious effects of the fumes evolved by electro-
lysis upon the conductors, which are directly exposed to their action, causing
deterioration of the material and making it difficult to maintain good contact between
the conductors proper of the accumulator and the connections of the leads which must
be mechanically attached to these conductors.
I obviate these difficulties by my invention, which is illustrated in the accompanying
drawing, in which Fig. 1 is a longitudinal section, and Fig. 2 a transverse section of
my improved secondary battery.
I preferably use bars or strips of solid peroxide A, arranged transversely in relation
to the conductors B, which are brought into contact with both sides of the bars A
forming the positive plates, such conductors being in the shape of combs made of
lead, compounds of lead, or other non-oxidizable metal.
The prongs of the combs B are in the form of loops and are not permanently con-
nected to the bars A of peroxide of lead forming the positive plates, but only rest
upon and are kept in contact therewith by pressure as hereinafter described.
Instead of bars or strips of peroxide of lead, I may use plates of same for the
positive plates, which the conductors surround as above described.
The negative plates are supplied with similar conductors B₁ on both sides. The

page_text: positive and negative plates with their conductors are then placed side by side and
separated either by a sheet of non-conducting material which is perforated, or by
strips D of such material arranged parallel to the bars of peroxide A and trans-
versely to the prongs of the conductors B, B¹.
By these means the outer surfaces of the conductors B, B¹, are brought into close
proximity to each other, the distance being determined by the thickness of the
insulating material D, whereas the space between the positive and negative plates is
comparatively large, allowing plenty of liquid to be used, which has been found in
in practice to be advantageous.
The prongs of the combs B, B₁, are preferably placed upright (as shown in the
drawings), in order to facilitate the escape of the gases evolved.
When a sufficient number of plates have been built up as described, the pile of
plates is furnished with a strong plate E of suitable material at each end. The whole
is then submitted to pressure, and while in that state all the negative conductors B'
are connected together and secured to one of the end plates E to form a terminal,
while the conductors B of the positive plates are similarly connected and led to the
other end plate E to form the other terminal. The pile in this compressed state is
thon inserted into a suitable box F, through the opposite ends of which it points in
line with the centre of the end plates, holes are formed and fitted with screwed
bushes G, made of lead or other non-oxidizable material. Pressure screws H work
through the bushos and bear upon the terminals on the end plates E, such screws
serving to maintain the pressure on the pile of plates and also form the external
terminals to which the leads are to be connected. The pressure is rendered yielding
by interposing an elastic washer I between the flange of bush G and the inner surface
of the box F. Moreover when the box F, as is generally the caso, is made of some
elastic material, the action of the screws H working through the bushes G and bearing
against the end plates E, bulges the ends of the box outward, thus enhancing the
yielding nature of the pressure.
Although a considerable pressure has to be used to keep the whole in proper
position, especially when bars or strips of peroxide are used for the positivo material,
by arranging my conductors in such a way that they shall be exactly opposite each
other a very great pressure can be exercised without fear of breakage, because the
material, although brittle and consequently liable to give way to a bending force, is
not friable.
The pressure, as all the surfaces are flat and the conductors straight and equal in
thickness, is sufficient in itself to keep everything in position, while allowing the
necessary play when any expansions or contractions take place, but for extra security
strips of lead b, 61, or other suitable material may be placed round the edges of the
spaces occupied by the peroxide, and connecting the loops of the conductors B, B¹,
respectively, thus forming a kind of enclosing frame. The loops B, B', forming such
frames may bo cast in one with the connecting strips b, 61, and the frames of the
different positive and negative plates are preferably connected together by broad
thin metal strips X, X', which may be burnt on in the usual way, and then connected
to the respective terminal plates E.
The elastic washers 1 with which the bushes G are provided further serve to render
the bushes water-tight.
By causing the terminals H to pass through the water-tight joints in the ends of
the box F, I am enabled to cover the whole with liquid, without leaving any terminals
exposed to the corrosive action of the injurious gases evolved.
The bushes G are so shaped or so mounted in the ends of the box F, that they
will not turn therein.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The construction of accumulators in which both the positive and negative plates
are surrounded by conductors, substantially as described and shown.

page_text: 2. The construction of accumulators in which the conductors surrounding the
plates (as specified in the preceding claim) are connected together, substantially as
described and shown.
3. The construction of accumulators in which both the positive and negative plates
and their respective conductors are firmly held in position with a yielding pressure,
substantially as specified.
4. The construction of accumulators in which all the plates are immersed in the
liquid, while the terminals pass through the ends of the enclosing box, substantially
as specified.