Improvements in Secondary Batteries
Year: 1897

page_text: I, ERNEST SCHATTNER of 146 Hithergreen Lane Lewisham London S.E. do
hereby declare the nature of this invention to be as follows:-
A total change in the construction of the plate.
My plate is as follows:-(1) The grid is made of a thin sheet of lead (or lead &
antimony) corrugated by special rollers.
In this grid slots are cut or stamped, to enable contact between the paste on each
side. The so constructed grid is pasted on each side in the ordinary way with the
ordinary paste. (2) The plate thus got is covered on each side by a flexible, porous
& acid-proof material, for instance the paper used by type writers as drying paper,
dipped into a solution of tungstate of soda or the like. (3) On each side of this
covered plate I put 2 (or more) long shaped slabs of porous earthenware.
The slabs on the top side are laid in opposite direction to the slabs on the bottom
side, thus giving great strength to the whole plate. These porous slabs are per-
forated by holes to enable the gas which is evolved while the cell is at work, to
get off. The 2 or more slabs covering each side are connected with each other
by a strip or strips of sheet indiarubber stuck on by Chatterton's compound or
indiarubber solution or the like. (4) Then the 2 sets of porous plates on each side
are connected also by indiarubber strips as above, so as to form a complete &
closed envelope. The reason of using indiarubber sheet to complete the envelope
is to prevent the porous plates from cracking, by the pressure of the paste when
expanding. (5) My plates do not stand up as in most cells but lie flat one on top
of the other, with separators between them.
Improvements in Secondary Batteries.”
I, ERNEST SCHATTNER, of 146 Hithergreen Lane, Lewisham, in the County of
Kent, 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 ascer-
tained in and by the following statement:-
-
My invention relates to certain improvements in secondary batteries and is
directed to the construction of the individual plates composing same with the object

page_text: of getting a plate which will have a greater life and less weight for a given capacity
than those at present employed.
I will describe my invention by reference to the accompanying drawing in
which,
Fig. 1 is an elevation of one side of a plate constructed according to my inven-
tion.
Fig. 2 is a section of same on line -- looking upward, and
Fig. 3 is an elevation of the other side.
In the drawings the section Fig. 2 is shown' of a considerably greater thickness
than it would be in practice for a plate of the proportions shown in Figs. 1 and 3
but this I have done for the purpose of clearness.
The usual grid a is made of a thin sheet of lead or lead and antimony alloy and
is preferably corrugated. In this grid slots b are cut or stamped to afford a hold
between the peroxide of lead or active material or paste c on both sides.
This paste c is covered on each side with a flexible, porous and acidproof material
such for instance as a stout blotting or drying paper d dipped into a solution of
tungstate of soda or the like.
On each side of this covered plate are two or more perforated slabs ee of porous
earthenware, acidproofed wood, wood boiled in paraffin wax, or other suitable
stiff or rigid acidproof material. The plates I prefer should not stand up when im
use but lie flat and the slabs e e which are on the upper side are laid in the
opposite direction to the slabs f f on the bottom side, thus giving great strength
to the whole plate.
I prefer also to form the perforations in the upper slabs e e larger than those
in the lower slabs f f to allow of the better escape of the gases evolved when the
plate is working.
The two (or more) slabe e eff on each side are connected with each other at
their four edges by strips of indiarubber sheet g g g g or the like. These strips
are bent over so as to enclose the edges and are secured to the slabs by cementing
them thereto with what is known as Chatterton's compound or with an india rubber
solution or the like. The two sets of slabs è e or fif are also connected by strips
such as h h which are also cemented down on the slabs. The slabs and strips. thus
form a complete and closed envelope of an elastic character the india rubber allow-
ing the porous plates to yield to the pressure of the paste when expanding so that
they are prevented from cracking.
The stiff or rigid perforated slabs further serve to effectively hold the paste in
position on the grid and to support same when the plates are in a horizontal
position. In fact the grid need only act as the electric conductor the perforated.
slabs taking the weight of the paste. The effect of supporting this paste by the
rigid slabs is that I am enabled to "form" the plate to a greater extent than is
possible with plates at prosent known to me as the paste though softening is
readily kept in position.
The plates are laid flat in the cells as stated, one on top of the other with
separators between them if necessary and an additional separator under one side
of the bottom plate, thus giving all the plates a slight slope upwards. Round the
whole section one or more indiarubber bands may be stretched to keep them
together.
I am aware that it is not new to employ a plate composed of a grid having the
active material on both sides, a retaining fabric or material and a perforated outer
cover, and I do not claim such as my invention but-
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 secondary batteries a plate in which the active material is supported or
protected by a perforated stiff or rigid slab or the like on each side which

page_text: 2. In secondary batteries a plate in which the active material is supported or
protected on each side by two or more slabs of perforated earthenware or suitable
stiff material, the slabs on one side being laid in the opposite direction to the slabs
on the other and being secured to each other by strips of india rubber or the like
elastic material substantially as and for the purpose described.
3. In secondary batteries a plate, the paste or active material of which is sup
ported or held to the grid with a uniform pressure all over same by a perforated
rigid envelope having elastic connections inserted in same substantially as and for
the purpose described.
4. In secondary batteries the means for elastically securing the rigid covering
slabs together substantially as described and illustrated in the drawing.
Dated the 5th day of November 1897.
PHILIP M. JUSTICE
55 & 56 Chancery Lane, London, Chartered Patent Agent,
For the Applicant.