Improvements in Electrical Accumulator Batteries.
Year: 1899

page_text: Date of Application, 16th Aug., 1899-Accepted, 7th Oct., 1899
Improvements in Electrical Accumulator Batteries.
I, EMILE PLACET, Engineer, of 18, Rue Denfert-Rochereau, Paris, France, 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 follow-
ing statement:-
My invention has for its object the construction of electrode plates for accu-
mulators which are both light and strong, which is always desirable, in particular
when the accumulators have to be fitted on vehicles, ships, and other moving
objects.
According to my improvements I employ for the said plates a light support
of a material which is either itself a conductor of electricity, or is rendered con-
ducting by the means hereinafter described, which support I coat on both sides
with a thick paste obtained by mixing glycerine with an oxide of lead such as
litharge, minium, peroxide of lead, or with a mixture of two or more of these
oxides.
This paste dries in a few hours in particular if the prepared plate is kept
between two metal plates slightly heated; I thus obtain very strong plates almost
entirely composed of active material, and which are well suited for either posi-
tive or negative electrodes.
It suffices to immerse these plates in acidulated water and to pass an electric
current through them in connecting them to the negative pole, in order in a
very short time to effect the transformation of the whole of the material into
very strong spongy lead, which adheres firmly and is very permeable.
The porosity of the plates can be increased by mixing with the lead oxide paste
above referred to powdered inert materials which, after the hardening of the
paste, will dissolve in a liquid, such as acidulated water; as such material may
be used starch or magnesia. Or materials may be employed such as camphor or
naphthaline, which will afterwards volatilize.
As the support for the electrode I can employ a sheet of ebonite perforated
with a large number of holes, and round which I wind some coils of wire or
narrow bands of lead or alloy of lead and antimony, before coating the two sides
with the above described paste.
Instead of a perforated sheet of ebonite, I may also employ a perforated sheet
of celluloid, gutta percha, linoleum, wood, paper asbestos, earthenware, or a
perforated and channelled carbon plate, or even felt, cloth, horsehair, canvas or
other similar minerals, which I thoroughly soak with either paraffin, bitumen,
caoutchouc solution, silicate, marine glue, and the like, so as to prevent the
support from decaying and from being attacked by the acidulated water of the
baths.
I obtain still lighter plates by employing wire gauze as the support. In this
case I take wire gauze of either copper, nickel, silver, lead, platinum, &c. and
I bend the sheet two or three times on itself so as to obtain two or three thick-
nesses, leaving between each two a space of from three to four millimetres; I
then coat the outer faces of this combined sheet and also fill in the spaces between

page_text: them with the oxide of lead paste above described, after which the plate is left
to harden.
The plates thus produced are both very light and very strong. If the wire
gauze used is of lead or platinum, the plates obtained can be used both as posi-
tive and as negative electrodes. But if the wire gauze be of copper, nickel,
silver &c., the plates can only be used as negative electrodes, as the wire gauze
would be rapidly dissolved if it were connected to the positive pole. In this case,
for forming the accumulators these negative plates with wire gauze support are
used together with positive plates having a support of ebonite or other analogous
material constructed as first above described.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim
is:
1. Electrode plates for accumulator batteries composed of a suitable support
covered with a thick paste formed of a mixture of glycerine with one or more
oxides of lead and constituting the active material substantially as described.
2. In electrode plates such as are referred to in the first claim, incorporating
with the paste of glycerine and oxide of lead constituting the active material
powdered inert material of a kind that will either dissolve or volatilise after the
hardening of the plate, for the purpose of rendering the active material porous,
substantially as described.
3. In électrode plates such as are referred to in the first claim, the use for
supporting the paste of glycerine and oxide of lead constituting the active material
of a sheet of ebonite, celluloid gutta percha, linoleum, wood, paper, cardboard,
asbestos, earthenware or carbon perforated and if necessary channelled, sub-
stantially as described.
4. In electrode plates such as are referred to in the first claim the use, for
supporting the paste of glycerine and oxide of lead constituting the active
material, of felt, cloth, horsehair, canvas, or other tissue saturated throughout its
thickness with paraffin bitumen, caoutchouc, silicate, marine glue or other sub-
stance that will protect the material from decay and from being attacked by the
electrolyte, substantially as described.
5. In electrode plates such as are referred to in the first claim, the use for
supporting the paste of glycerine and oxide of lead constituting the active
material of wire gauze folded on itself, both the outer surfaces and the spaces
between the folds being filled with the said paste, substantially as described.
Dated this 16th day of August 1899.
ABEL & IMRAY,
Agents for the Applicant.