Improvements in Secondary Batteries.
Year: 1886

page_text: Date of Application, 4th Oct., 1886.
Complete Left, 4th July, 1887.
Complete Accepted, 5th Aug., 1887.
Improvements in Secondary Batteries.
EMILE ANDREOLI, Journalist, of 62 Loughborough Park, Brixton, Surrey do hereby
declare the nature of this invention to be as follows:-
In the construction of secondary batteries of the Faure system or its congener,
there must be a support on which the active material is applied, and patents have
been taken for electrodes for secondary batteries composed of plates of lead or of
sheets of lead, or pieces, grids etc., which are roughened serrated, ribbed, perforated,
interstical, corrugated, fluted, indented, cellular, etc., or of perforated strips, tubes.
pieces or woven fabrics of lead, etc., on or in or against which oxides or salts of lead
or spongy lead are packed, deposited or attached, the perforations or interstices being
in such a form that the material with which the perforations or interstices etc. are
packed must be keyed or firmly retained in such a position, by the shape of such
numerous divisions perforations, opening receptacles, holes etc., such perforated sheets
are merely supports and retainers which hold the pasty material, which will be after-
wards converted into peroxide of lead and porous lead, so that it cannot fall through or
out of the said perforations, slits or openings, or readily break off or away from its
position.
My invention relates to the construction, not of internal supports, but of light
metallic internal conductors, by means of which the conductibility of the electrodes
may be increased, and my object is, in no way, to retain any particle of active
material, since according to my two specifications, No. 8842, lodged July 6th 1886,
and No. 11040, lodged August 30th, I can construct plates made entirely of active
material, without any support oxidisable or non-oxidisable.
To carry out my invention, I use a delicate metallic structure, in the shape of
netting, having some very large meshes or of a web or reticle, and I imbed this
conductor of electricity in the mass of active material of my plates. This metallic
skeleton can be made of thin threads of lead or alloy of lead or other suitable
metals so that the weight of my plates is not increased and they have a greater
conductibility.

page_text: I prefer to employ massive electrodes, I may however, if convenient, considering
that peroxide of lead is not a good conductor, obviate to this bad conductibility by
using an internal metallic conductor, so that when my plates are thick, the whole of
the active material and not only the surface will work, and that as well in forming as
in charging and discharging, I obtain better results than with any other system of
plates, representing the same surface and the same weight.
Discarding all the schemes and devices for internal supports which hitherto have
been patented for giving strength and durability to the plates and for facilitating the
packing, depositing placing or fixing the active material in openings, receptacles,
holes etc., I employ as an internal conductor for my plates, made of molten chloride
of lead cast in moulds, square or rectangular plates, diagonal arrangement of lead
wire or any suitable metallic wire; this metallic internal arrangement of thin
conductors may be forked, zigzagged, wedge-shaped, or the diagonals may be curved,
deflected, corrugated, arched, or in the centre of my plates, I may havo thin, per-
pendicular or horizontal bars, attached to the upper part of the frame; the internal
conductors may be of a concentric form, in contact with the frame, in order to facilitate
the prise de courant, or they may be retiform, crescentric, luniform, semi-lunar, arc-
shaped, convoluted, spiral, sinuous, reticulated, digitated, starlike, pectinated or may
consist of a very thin metallic network, with large interstices, or even of a few
metallic threads, inserted in the molten active material and which I may cross or
intersect as suitable and place in the most convenient way for getting a large rate of
discharge.
1
1000

page_text: Solid plates of peroxide of lead, especially when very thin and perforated, may
answer for certain purposes, provided no high rate of discharge is required.
But the conductivity in solid plates of peroxide of lead is not the same on all points
of the surface and their capacity does not depend upon the thickness of the plates, and
the want of conductivity inside the solid slab is still greater, and although by certain
ingenious devices, some electricians have succeeded in making local contacts by means
of non oxidisable metal, such as platinum or other metals, and have obtained some
comparatively good and satisfactory results, as far as increasing the conductivity of
the positive electrode (peroxidised) they however did not obviate in a sufficient manner
to the draw back inherent to them of a mass of peroxidised lead, which being not by
itself, a good conductor, and being an agglomerated mass of oxides of lead, rendered
solid by mechanical pressure, cannot supply a good current, i.e., discharge at a
rapid rate.
Solid plates of peroxide of lead, manufactured by means of fusion of salts of lead,
in combination with other salts of lead or of other metals which afterwards are treated
as substantially described in the above mentioned specification are quite porous and
are more conductive than the solid slabs of compressed oxides transformed into
peroxide of lead and through which the current does not run without encountering a
great resistance.
When submitted to heavy work, such electrodes obtained in a solid form by
mechanical pressure have not their active material utilized. as it ought to be, because
to the thickness of the peroxide of lead slab does not correspond any proportionate
output as one would believe, simply by calculating the capacity supposed to be stored
per ounce or per pound of active material, and because, so to speak, the external
surfaces alone of the electrodes supply the electrical energy, while their internal parts
remain almost inert compared to the energy they would give if there was a good
conductor, which, by its system of canalisation or of ramification through the plate,
would equally and regularly collect the current at all the points of the peroxide of lead
mass on charging and distribute in the same way on discharging.
The great desideratum in a solid mass of peroxide of lead is what French electricians
call the: Prise de courant, and in my experiments in view of securing good contacts
on my peroxide of lead electrodes, I have found different means of increasing their
conductivity, according to the object. I had in view, i.e. to the rate of discharge I
wanted.
I have successfully surrounded my plates with frames of lead, lead and tin or lead
and another metal which does not produce or produces very little local action. In
using such plates, I observed that when the plates are thick they are easily peroxidised,
provided great care is taken in forming and charging, but when they are thin, they
contract, expand and warp, because being surrounded and firmly kept by the frame,
there is no allowance for the expansion and dilatation of lead when peroxidising, and
the plates consequently buckle and bend, and finally exfoliate and break because the
lead frame has no elasticity and the volume of the peroxide increases.
I also use frames which partially surround the plates and do not completely encircle
them with a rigid belt, while however they make a good contact: still better contacts
through the whole internal structure of the crystalline peroxide of lead are made by
means of platinum wire network or of a thin copper wire coated with platinum, electro-
litically deposited; but although this coating of platinum does not sensibly increase
the cost price of the plates, but it is an item of expenses which cannot be neglected
and for this reason, I do not recommend it, except for some special work, as the
case may happen.
A very important and characteristic feature of this invention in the manufacture of
electrodes for secondary batteries, and on which I must insist, is that I never want
any support or retainer or retaining frames to key up or to firmly keep the active
material, and it must be clearly understood that I do away with and emphatically
disclaim the use of any such support or retainer of any form or shape on, in or against
which oxides or salts of lead or spongy lead are packed, deposited or attached, their

page_text: interstices, holes or perforations being in such a shape that the active material with
which these interstices, holes or perforations are packed, must be keyed or firmly
secured and retained in its position by the shape of those numerous divisions,
perforations, openings, receptacles, grooves slots, corrugations, reticulations, etc.
The grids or perforated sheets of lead or alloys of lead of the Electrical Power
Storage Company and other similar systems are essentially supports and retainers, the
substratum on which the whole edifice rests, the scaffolding on which the masonry is
applied and without which the pasty material of oxides of lead, which must be
converted into porous load and peroxide of lead, would not be able to keep or even to
resist a feeble current, but would fall to pieces.
My plates are solid and self-standing and they do not require any sustainer or any
internal metallic support or retainer, to prevent their disintegration or destruction or
to strengthen them. I can do without retainer or even without any conductor, but,
sometimes, my positive plate although composed of pure, porous, crystalline active
material, and therefore less liable than any other to distort and contract or expand,
does not give up the amount of energy and work 1 may require, and this is the reason
why I use, not a retainer or support heavier than the active material with which it is
coated, constituting an expensive dead weight and a considerable source of local action
and sulphatation caused by the thickness of its texture. On the contrary, I use a very
light and delicate structure, which as an internal system of conductors, allows me to
have a great capacity and presenting more elasticity than the thick retainers of the
other batteries, is not a source of buckling, and finally, being very thin and specially
prepared before they are imbedded in the fused metallic salts, do not cause local
action.
The spongy lead plate does not require any internal conductor to increase its con-
ductivity, therefore it is clear enough the grid of the Electrical Power Storage Company
and other similar systems is really a retainer and support and it cannot be alleged that
it is a conductor. In short, the object of the invention of the grids, etc., has solely
been the retention of the active material encased in the holes, interstices, etc., and in
none of the Faure Sellon Patents there is any mention of using grids, gridirons etc.
as conductors in order to increase the conductivity and effectiveness of the plugs of
active material incased in their holes.
These patents and all the other patents granted to inventors of similar systems for
constructing plates for accumulators claim without a single exception the use of
oxides of lead, pasted on two grids, one of which is in the positive and the other one
in the negative electrode.
There must be unavoidably two grids, one to support, sustain and retain the spongy
lead and the other one to support, sustain and retain the peroxide of lead, and the
only difference between them is that for sake of convenience in forming, one of them,
is thinner or smaller and lighter than the other one. But, it is a sine qua non
condition of the possibility of constructing such plates that they are composed of
oxides of lead compressed in grids, which are their base, their ground work.
It is a well known fact that but for this necessity of perforations or interstices in
grids, in such a form that the material with which the perforations or interstices are
packed, will be keyed or firmly retained in position, or of terminal plates, supports
retainers or frames upon which the active material or agent is deposited, placed or
fixed, there would really be no internal grid required for the spongy lead plates of
the Faure Sellon or of other similar systems.
Spongy lead is sufficiently conductive without retainers and even without
conductors, but unless there is something to fasten the spongy lead, in a strong
cellular reticle, there cannot be any spongy plate constructed, and this is an irrefutable
proof that the grids used and claimed in their specifications by the inventors of the
above mentioned systems of accumulators, are purely retainers or supports and
cannot be assimilated to conductors.
In my battery, it is quite the reverse: the negative plate (reduced lead) is by
itself firm and strong enough to resist manipulations, especially when in a suitable

page_text: metallic frame, and I never imbed in it any internal net wire work or skeleton or any
conductor whatever, because the conductivity of the porous lead mass is quite sufficient.
For my positive plate (peroxide) I find however sometimes necessary, as herein
above stated to have an internal structure or web, which as aforesaid is very light,
is made of a substance which constitutes with peroxide of lead a very slight local
couple if any and establishes a complete and equal distribution of the current
outside and inside, on all the points of the positive plates and increases their
conductivity by the multiplicity of the contacts. There can therefore be no
comparison of my internal conductors, whatever may be their shape and size, with
the usual grids retainers, etc., as they are used solely in order to convey more
rapidly the current, and by their nature, cannot be anything but conductors, & because
my object has never been to have an internal arrangement which prevents the
active material from falling through or out of the perforations, slits, openings, or
breaking off or away from its position; and without infringing any claims of
inventors of retainers, grids supports etc., I use thin conductors which may be as I
chose: roughened, serrated, ribbed, perforated, interstical corrugated, indented, or
woven fabrics of lead or any alloy or other metal, because I do not employ them
to pack or deposit on, in or against them oxides of lead or spongy lead but use
them only in order to increase the regularity and rapidity of the discharge.
The devices for conductors are numerous: for instance, I make a network of wire
fitting exactly in the shells of my mould and I cast on it the molten salts of lead so
that I have a thin plate which on both sides is externally covered with a metallic
network, which on the whole and inside of the surfaces acts as a conductor.
The internal metallic arrangement of thin and light conductors may be forked,
zigzagged, wedge-shaped or the diagonals may be curved, deflected, corrugated,.
arched, or sometimes, in the centre of my plates, I may have several perpendicular
or horizontal bars attached to the upper part of the frame, or the internal conductors
may be of a concentric form, in contact with the frame in order to facilitate the
prise de courant, or they may be retiform, crescentric, luniform, semi lunar,
arc-shaped, convoluted, spiral, sinuous, reticulated, digitated, starlike stelliform,
pectinated or may consist of a very thin metallic gauze with large or small interstices
or even of a few metallic threads, inserted in the active material, and which I
may cross or intersect as suitable and place in the most convenient way for getting
a large rate of discharge.
.
I use also an extremely thin grid or trellis of lead or lead alloy, such as antimony
or with a very little quantity of selenium, which renders the grid less fusible, while
at the same time, I may increase the fusibility of the salts of lead, by mixing them
with salts which fuse at a lower temperature.
I also sometimes employ an iron or steel conductor, in the shape of a fork or comb
or grid etc. which I introduce in the mould where the plate is cast. The iron may be
either in the passive state or not, I prefer to use an iron or steel wire network which
I first dip in a bath of nitrate of lead or other salts of lead or other metal on which
a coating of peroxide is deposited by the electric current. I then cast the fused salts
of lead in the mould where the iron web or gauze has been placed, and I have then
an internal conductor which is still lighter than a lead grid or wire.
From a point of view of the increase in the discharging capacity of the plates, I
must point out this important advantage of these internal conductors in plain or
perforated slabs of peroxide of lead, that the quantity of active material represented
by the plugs of the Faure Sellon and other similar systems, fits exactly in the holes of
the grids which, in the same way as a glass does not contain liquid over its brims,
can not contain active material beyond the surface of the grid, and any attempt to
have over the surface of the grid a layer of compressed oxides would prove to be a
failure, for this simple reason that as soon as there no longer any retainer, there is
no active material retained. It has been recently ascertained by practical men what
the proportion of active material is for a given weight of retainer or grid, and the
superiority of my system lies in this fact that my conductors are very thin and light,
that they have not any appreciable deadweight, that a given weight of my positive

page_text: plates will represent more active material than the same weight of any other plates,
and while the conductivity of my plates is at least equal to that of the others, their
nature allows me to make them a little thicker and to embed the grid in the
centre of the mass, in such a way that the external surface of peroxide of lead may
work efficiently without conductors and that as soon as the external layer of peroxide
of lead is exhausted or its current decreases, the internal conductors act and convey
the electrical energy to the outside, instead of its being prevented by the resistance
from yielding a constant rate of energy.
Having now 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 :
1st. In the manufacture of Secondary batteries, the use of positive electrodes
brought to the state of peroxide of lead or of other metal, by a special treatment of
metallisation and dechlorination and the available capacity of which is increased by
inserting, embedding or attaching in, on or through them internal conductors of any
size or shape, which I distinctly declare not to act as retainers or supports of the
active material in their cavities interstices, spaces, cells, but exclusively as conductors
capable of conveying the electrical current, of facilitating the rapidity of the discharge
and of yielding a greater quantity of utilizable energy.
2nd. The peculiar combination and arrangement of inserting, embedding or
attaching in, on or through a solid or perforated plate a conductor of lead, or lead
alloy or. any suitable metal such plate being made of fused and cast salts of lead or
other metal treated and transformed into electrodes of pure active material, as
described in my complete specification dated 6th July 1886, No. 8842, and such
conductor or conductors being of any shape or size and their main feature being that
they are not intended to act and do not act as retainers or supporters.
3rd. The use of an internal iron or steel core or network with large or small
meshes of wire or of a perforated passive iron thin plate in the manner substantially
hereinbefore described.
4th. The combination and employment of conductors in positive electrodes for
increasing the rapidity of the discharge, and also in negative electrodes in case it
happens I wish to convert them by oxidation into conductive positive plates.
5th. And finally the use of conductors made of any suitable metal and in any
shape or size in the manner and for the purposes substantially as described in this
specification.
Dated this Fourth day of I-11007