Year: 1887

page_text: Date of Application, 19th Sept., 1887
Complete Left, 16th June, 1888
Complete Accepted, 20th July, 1888
accumulators and consists in producing this lead by making use on
action and then an electrical action.
first
If the
I take a compound of lead (oxide, chloride, sulphide, bromide or other); if this
compound is fusible I melt it and run it into frames formed of ordinary lead or of an
alloy of lead and antimony or any other metal which gives it more rigidity.
lead compound is not fusible I mix with it oxides which will render it fusible such as
oxides of iron, manganese, zinc &c., or I mix the lead compound with sal-ammoniac
either alone or mixed with or more metallic oxides. If the lead compound is litharge
I melt it in crucibles or melting pots made of calcined and agglomerated bone which
will resist the attacks of oxygen during the fusion of the litharge and allow of its
being run out; it is not practicable to melt litharge in crucibles or pots such as are
ordinarily employed.
When the mixture of the lead compound and its flux has been obtained I melt it
and run it into frames such as are above described.
The reduction of the lead compound into spongy lead is effected by means of an
electric current and this can be carried out in various ways. I can employ for
example a foreign source of electricity such as a dynamo machine, a battery of piles,
or a battery of charged accumulators; in this case I place the cast plates in a bath
of acidulated water and connect them together so as to form with them the negative
electrode of this kind of voltameter; the positive electrode is formed by carbon plates
interposed between the cast plates and separated from them electrically by strips or
pieces of insulating material.

page_text: When I send the current from the source of electricity into this voltameter, the
acidulated water is decomposed, the oxygen goes to the carbon plate and is disengaged
and the hydrogen goes to the cast plate entering into combination with the body with
which the lead is combined; consequently this lead is restored to the metallic state.
The operation is continued until the reduction of the lead compound into spongy lead
is complete.
I can also form a battery or pile the soluble electrode of which can be anything
suitable while the positive electrode is formed of my plate of lead compound. If I place
in acidulated water a plate of zinc and a plate of lead compound and connect the zinc
to this plate by a wire I set up an electric current, the zinc is dissolved in the form of
a zinc salt and the hydrogen which is disengaged goes to the lead compound and will
bring it to the state of spongy lead. As before, the operation is continued until the
reduction of the lead is complete.
After having formed these plates of spongy lead it is only necessary in order to
constitute an accumulator element to mount them in the usual manner in a vessel
containing acidulated water, to insulate them electrically and to connect together all
the alternate or even plates to form one of the electrodes of the accumulator and all
the other alternate or odd plates to form the other electrode.
Dated this 10th day of Santambar 1807
J. C. MEW BURN,
169, Fleet Street, London,
Agent.

page_text: Improvements in the Manufacture of Spongy Lead suitable for
Electrical Accumulators.
I FRANÇOIS MARIE ARTHUR LAURENT-CELY of 1 Boulevard St. Denis, Paris,
France, Chemist and 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:—
My invention has reference to the manufacture of spongy lead suitable for electrical
accumulators.
I take a compound of lead as for example litharge, sulphate of lead, chloride of
lead, &c., and I submit it to igneous fusion; I then run or cast it into any desired
form, and I finally reduce it to spongy lead and this I effect by means of hydrogen
obtained by the decomposition of water by an electric current.
The spongy lead thus obtained has little density, is very porous, and is suitable for
the manufacture of accumulator plates of any thickness.
According to the particular lead compound employed certain precautions should be
taken in melting it. Lead compounds may be divided into two categories. The first
does not attack crucibles or bricks of refractory earth. The second takes up the
silica contained in the refractory earth and forms silicate of lead.
In order to melt lead compounds of the first category, of which I will take chloride
of lead as a type, I use simply a crucible made of refractory earth or a furnace the
sole of which is made of refractory bricks. After melting I run this chloride either
into cast iron moulds or into sand moulds in order to obtain blocks which can be used
afterwards to form accumulator plates or I run the chloride directly into conducting
supports or frames formed of antimonious lead. I will describe further on how I*
prefer to make these castings. After casting and cooling, the chloride of lead is
brittle. I give it strength or firmness by adding to it before melting a small pro-
portion of chloride of zinc. This proportion can vary without inconvenience from
to 15 per cent. of the total weight of the chloride of lead. I sometimes produce this
chloride of zinc at the expense of the chloride of lead itself by adding metallic zinc
to the chloride of lead after it has been melted. The zinc displaces the lead from its
combination with the chlorine to form chloride of zine and the metallic lead obtained
falls to the bottom of the bath on account of its great density. It is collected
separately after the casting.
In order to melt lead compounds of the second category of which I will take
litharge as a type I employ a furnace with a sole of basic material. This sole will
generally be formed of powdered bones agglomerated with a little caustic potash.
It can also be formed by aluminium, lime, magnesia, or the like agglomerated
with a binding material containing very little or no silica.
As with the chloride of lead, I can add to the litharge certain compounds either to
render it firmer after melting or to diminish the density of the spongy lead obtained
after its reduction. I may particularly mention hydrochlorate of ammonia and

page_text: chloride of lead which by their fusion with litharge cause the formation of oxychlorides
of lead into which the litharge can enter in any proportion.
When the lead which I employ is sulphate of lead, as this is almost infusible I add
to it litharge in any proportion and thus form a basic sulphate of lead which is almost
as fusible as litharge itself.
Having explained the general processes which I adopt for melting the lead
compounds I will now explain the processes I follow for casting and moulding them
into accumulator plates.
(1). I cast separate blocks of any form and after having arranged them in a
mould made for the purpose I run into this mould antimonious lead to connect
all these blocks by means of a conducting support. This method presents no
difficulty because the melting temperature of antimonious lead is much lower than
that of the lead compounds of which the separate blocks are formed. The casting of
the separate blocks is made in sand moulds or in cast iron moulds with "dead-
heads of such form and dimensions that the body of the blocks will be sound
and without air holes or faults.
(2). Or after casting the blocks I set them in a conducting support of anti-
monious lead and this can be advantageously done in the manner that window
panes are set in lead frames.
Sometimes I employ conducting supports made in two parts; I place in the
lower part the blocks of lead compound, I then put on the upper part and connect
the two half supports by lead rivets. Figure 1 of the drawings illustrates in
section this manner of securing the blocks. a, a, a represent a portion of the lower
half support. P, P are the blocks of lead compound placed in the spaces of this
half support. b, b, b represent a portion of the upper half support and c is one
of the rivets which connect the two half supports together.
(3). I will now explain a method by which the molten lead compound can be run
or cast directly into a conducting support of antimonious lead without affecting
this support although the melting temperature of the lead compounds is higher
than that of the antimonious lead. It consists in placing the conducting support
between top and bottom plates the lower of which is solid while the upper has
holes or ingates which are so arranged that none of them comes above a part of
the support. By this arrangement the molten lead compound which runs into the
space in the frame or support does not touch the support directly and therefore
does not melt it.
Figure 2 represents a mould of this description. A is part of the solid bottom
plate. b, b, represent part of the conducting support the form of which differs
somewhat from that shown in Figure 1. B is part of the top plate formed with
holes or ingates c, c.
Above it is a funnel E into which the molten lead compound is
poured. The two plates are connected together by clamps F. It will be noticed
that the holes c come above spaces in the support and never above the bars of this
support. Consequently at the time of casting the bars are protected from direct
contact with the molten lead compound. In some cases I have several holes or
ingates c, c for each space of the support b, as seen in Figure 3. The holes or
ingates c may be of any desired form but the form shown in Figure 3 is specially
recommended as holes of this form are not liable to get stopped before the solidification
of the lead compound in the spaces of the support 6, such premature stoppage
causing air holes or faults in the casting.
The lead compound is now reduced into spongy lead and this is effected by means
of hydrogen obtained by the decomposition of water by an electric current. This
reduction by means of hydrogen can be carried out in various ways. I can employ
for example a foreign source of electricity such as a dynamo machine, a battery of
piles, or a battery of charged accumulators; in this case I place the cast plates of
lead compound in a bath of acidulated water and connect them together so as to form
with them the negative electrode of this kind of voltameter; the positive electrode is
formed by carbon plates interposed between the cast plates and separated from them
electrically by strips or pieces of insulating material.

page_text: When I send the current from the source of electricity into this voltameter, the
water is decomposed, the oxygen goes to the carbon plate and is disengaged and the
hydrogen goes to the cast plate entering into combination with the body with which
the lead is combined; consequently this lead is converted to the metallic state.
operation is continued until the reduction of the lead compound into spongy lead
is complete.
The
I can also form a battery or pile the soluble electrode of which can be anything
suitable while the positive electrode is formed of my plate of lead compound. If I
place in acidulated water a plate of zinc and a plate of lead compound and connect
the zinc to this plate by a wire I set up an electric current, the zinc is dissolved in
the form of a zinc salt and the hydrogen which is disengaged goes to the lead
compound and will bring it to the state of spongy lead. As before, the operation is
continued until the reduction of the lead is complete.
The hydrogen for the reduction of the lead can be obtained by a chemical reaction
in any of the known mauners instead of by the decomposition of water by an electric
current as described, or any other known reducer can be employed instead of
hydrogen.
After having formed these plates of spongy lead it is only necessary in order to
constitute an accumulator element to mount them in the usual manner in a vessel
containing acidulated water, to insulate them electrically and to connect together all
the alternate or even plates to form one of the electrodes of the accumulator and all
the other alternate or odd plates to form the other electrode.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, declare that what I
claim is :-
1. The process herein before described of manufacturing spongy lead suitable for
electrical accumulators, that is to say, by melting a lead compound, then running or
casting it in conducting supports, or casting it into blocks which are subsequently set
in conducting supports, or casting it into blocks which subsequently have conducting
supports cast around them, and then reducing the lead compound to the state of
spongy lead by means of hydrogen obtained by the decomposition of water by an
electric current, substantially as set forth.
2. Manufacturing spongy lead suitable for electrical accumulators as herein before
described.
1000
J. C. MEWBURN,
169, Fleet Street, London,
Agent.