Improvements in Accumulator Batteries.
Year: 1899

page_text: Improvements in Accumulator Batteries.
I, PASCAL MARINO, of 77, Rue des Foulons, Brussels, Belgium, Chemist, 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:-
This invention relates to the construction and arrangement of the electrodes,
the composition of the electrolyte and the means of forming the plates of accumu-
lator batteries, in such a manner as to ensure large and rapid production of
electrical energy, firmness of the battery and protection of the active material
against the loosening action of shocks or vibration.
For this purpose I construct and arrange the electrode as I shall describe
referring to the accompanying drawings shewing electrodes of rectangular form.
Fig. 1 is a front view of the porous partition interposed between each pair of
positive and negative electrodes, this partition being made of asbestos or magnesia
paste or unglazed porcelain.
Fig. 2 is a front view of a positive plate, being a sheet of flat or corrugated lead
preferably perforated with numerous holes and provided with a conducting lug
at one side. Fig. 3 is a front view of a negative plate being a sheet perforated
or not of lead, aluminium or other metal, and having a conducting lug on the
side opposite to that of the positive plate.
Fig. 4 is a perspective view shewing a number of alternating positive and
negative electrodes separated by the porous partitions and superposed, all the
lugs of the positive electrodes being soldered to a conducting bar and those of
the negative electrodes to a bar b, while the whole of the electrodes and partitions
are bound by non-conducting ties of material that is not acted upon by acid.
The positive plates are coated with one or more layers of active material con-
sisting of minium or a mixture of finely pulverized minium and graphite formed
into a paste by mixing it with an aqueous solution of gun cotton dissolved in
caustic alkali with addition of benzene or the like. The negative plates are
coated in like manner, lithage being substituted for minium.
For forming the plates they are insulated from each other in a vessel containing
a solution of sucro-glycerate of calcium, barium or strontium and connected to a
source of electricity, the forming being accelerated if desired by first passing
the plates through a solution of double sulphate of lead and ammonia.
The electrolyte consists of distilled or rain water to which is added any of
the acids resulting from combination of phosphorous and oxygen, and especially
a little hypophosphorous acid.
Datal this let dow of Tune 1800

page_text: Improvements in Accumulator Batteries.
I, PASCAL MARINO, of 77, Rue des Foulons, Brussels, Belgium, Chemist, 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:
-
This invention relates to a new electric accumulator essentially characterised by
the nature, construction and formation of its electrodes and its electrolyte, as I
shall describe referring to the drawings accompanying my Provisional
Specification.
Each element consists of one or more negative and positive electrodes made
as follows:-
1. Each positive electrode is a thin sheet of lead flat or corrugated and prefer-
ably perforated with numerous holes. It is covered by a brush with one or
more successive layers of active material, consisting either entirely of minium
or of a mixture of minium finely pulverised and graphite. In order to render
the active material fluid and adherent, it is mixed with a liquid consisting of
about 10 grammes of dry gun cotton introduced into a deep vessel and having
poured on it. distilled water enough to cover the cotton; to this are added
about 55 grammes of caustic soda or potash. The caustic salt in dissolving
heats the liquid which in some places turns. yellow, the gun cotton decomposes
and completely disappears by the reaction which it undergoes. On completion of
the action a liquid of deep brown colour is obtained to which is added benzene or
similar hydrocarbons, the object of which is to clear off the fatty matters which
may be on the metal and also to render the material more adherent. The whole
being mixed with the active material is applied by a brush to the lead sheets.
2. Each negative electrode consists of a flat or corrugated sheet which may be
perforated or not, of lead, aluminium or other metal, covered like the positive
electrode, but with litharge instead of minium.
3. Porous rigid partitions of asbestos or magnesia paste or of unglazed porce-
lain or of other porous rigid material, separate the positive from the negative
electrodes. Such a partition is shown in plan in Fig. 1.
4. For conductors each electrode, as shewn in plan in Figs. 2 and 3, has a
projecting lug on one side, and all the lugs of the electrodes of the same sign
are soldered vertically together to form the conductors, positive on the one side
and negative on the other side.
5. The complete element which may be square or rectangular according to
the shape of the plates, thus consists as shewn in Fig. 4, of a number of horizontal
positive and negative electrodes, superposed and alternating and separated by
the porous partitions described under 3, the whole stiffened by soldering to the
lugs two bars a and b which constitute the conductors. The whole pile is bound
solidly together by ties that are not attacked by acids and are not conductors.
It might be thought that the porous partitions cause internal resistance, but
this is not the case, for as soon as circuit is completed, the accumulator yields
current like ordinary accumulators. For instance, if a kilogram of electrodes
having at least five pairs of plates be placed in the forming bath consisting of
double sulphate of lead and ammonia, hereafter described, meters indicate after
about 10 hours formation, about 21 volts, and 10 to 12 ampères, which is the
best proof that the lead oxide is reduced to active material and that the porous
partitions cause no internal resistance.
G. The electrolyte liquid consists of distilled or rain-water with addition of
phosphoric or phosphatic acid (2P, O. P O or phosphorous or phosphoglyceric
acid, or briefly any acid resulting from the combination of phosphorus and
oxygen. It was ascertained that during discharge of the elements the reduction

page_text: of the lead peroxide occurred in an incomplete manner, and consequently that
the presence of peroxides in the electrolyte caused an opposing electromotive
force which explained irregularities of charge and discharge. This defect is
avoided by adding to the electrolyte drops of hypophosphorus acid, which
has the effect of rendering the reduction of lead peroxide complete and gradual
during discharge.
7. For forming the elements, I proceed as follows: In a suitable receptacle
the electrodes are arranged insulated from each other, and connected alternately
to the positive and negative terminals of a source of electricity in a forming
electrolyte consisting of a solution of sucroglycerate of calcium, or of barium
or strontium, made, for example, by dissolving 15 to 20 parts by weight of sugar
and 10 to 12 parts by weight of calcium glycerate in 100 parts by weight of
water. By the electric action there is obtained a layer of lead binoxide formed
from the pure lead covering of the positive electrode; and the negative electrode
becomes modified assuming a granular condition very favourable to the chemical
action which should take place in the accumulator.
In order to accelerate the forming, the electrodes are in the first place passed
through an electrolyte consisting of a solution of double sulphate of lead and
ammonia, which is obtained by precipitating lead acetate by sulphuric acid and
saturating the excess of sulphuric acid and the liberated acetic acid with ammonia.
Under the action of an electric current of at least two volts, the positive electrodes
become covered with a deposit of lead peroxide, and the negative with a deposit
of spongy lead.
The advantage of the system described over other known systems are numerous,
the chief being as follows:-
The output in capacity is greater without increase of the specific capacity
(weight and volume).
The use of two porous partitions within the envelope gives it such a rigidity
that movements causing short circuit cannot take place.
The solidity of the electrodes allows of increased charge and greater output.
The protection of the active material by the porous partitions renders falls of
it impossible whatever be the shocks or vibrations to which the elements are
subjected.
The formation being very rapid, the discharge is obtained immediately on
closing circuit.
Having now particularly described and ascertained the nature of this
invention and in what maner the same is to be performed, I declare that what
I claim is:
1. An accumulator battery consisting of positive and negative plates prepared
as above described, separated by porous partitions and superposed, the plates
having projecting lugs soldered respectively to positive and negative conducting
bars, substantially as described.
2. The method of forming the plates by immersing them insulated from each
other in a solution of sucroglycerate of calcium. barium or strontium.
3. For accelerating formation of the plates before treating them as set forth
in the preceding claim, passing them through a solution of double acetate of lead
sulphate and ammonia under the action of an electric current.
4. For a battery of the kind described, an electrolyte consisting of pure water
with addition of an an acid resulting from the combination of phosphorus with
oxygen, such as those above set forth.
Dated this 23rd day of December 1899.
ABEL & IMRAY,
Agents for the Applicant.