Electrical Accumulators
Year: 1886

page_text: Date of Application, 16th Aug., 1886
Complete Left, 17th Jan., 1887
Complete Accepted, 4th Mar., 1887
I, EDWARD FRANKLAND F.R.S. of Reigate Hill in the County of Surrey
Professor of Chemistry do hereby declare the nature of this Invention to be as
follows:-
This Invention relates to the construction of the plates of Storage Batteries or
Electrical Accumulators.
The plates of many forms of storage batteries have hitherto lacked permanence
owing partly to bending or buckling and partly to the gradual detachment of the
active composition from the metallic portion of the plates both these effects being
brought about by the expansion of the active material during the use of the
battery.
My Invention has for its object the avoidance of these destructive effects firstly by
so enclosing or embedding the active composition in the metallic portion of the plate
as to prevent its falling out and secondly by giving sufficient strength to the plate to
enable it to resist bending or buckling.
.
In carrying out this my Invention I employ as active material the hardening
mixture of oxide of lead and sulphuric acid for which letters Patent were granted to
me in the year 1882 (No. 4303) and whilst this mixture is in a pasty condition I
mould it into small cylinders or rods of convenient length and thickness either by
rolling, pressure through a draw plate or tube, or other convenient means and I then
flatten them on two opposite sides by pressure between two flat boards or otherwise.
Or I may similarly employ the oxides or salts of lead.
After these flattened cylinders have become sufficiently hard I place them in rows
in a
casting mould of dimensions corresponding to the size of the battery plate
required and at such distances apart and from the edges of the mould, as to give
sufficient space for the quantity of metal necessary to impart adequate strength and
rigidity to the plate. I then pour into the mould suitable molten metal such as lead
or an alloy of lead and antimony until the interstices between the flattened cylinders
are completely filled. In this way a plate is obtained in which the active material is
encased except on the flattened sides of the cylinders overlaid with metal so that it
cannot subsequently fall out during the charging and discharging of the battery or
even when subjected to considerable rough usage.

page_text: Instead of operating in the manner just described I sometimes carry out my
Invention as follows: I roll the hardening mixture whilst still soft into a thin cake
which I allow to harden. I then break up this cake into small fragments and after
sifting out any dust place these fragments in the mould already described so as to fill
it or nearly so. I may also use for this purpose, fragments of the other active
materials already alluded to. I then pour molten metal into the mould so as to fill
up all the interstices. The fragments of active material are thus imbedded in the
metal, but in such a way that they obtrude at the two surfaces. The surfaces of
plates so prepared may afterwards be planed if desired, so as to expose a larger
surface of active material but this is not usually necessary. These plates are very
strong and may be subjected to very rough usage with impunity.
It is obvious that the mode of carrying out my invention may be varied but its
essence consists in the imbedding of the active material in storage batteries in suitable
molten metal.
J. HENRY JOHNSON,
47, Lincoln's Inn Fields, W.C.,
Agent for E. Frankland.

page_text: COMPLETE SPECIFICATION.
Improvements in the Construction of Electrical Storage Batteries.
I EDWARD FRANKLAND F.R.S. of Reigate Hill in the County of Surrey
Professor of Chemistry 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 of the plates of Storage Batteries or
Electrical Accumulators.
:
The plates of many forms of storage batteries have hitherto lacked permanence
owing partly to bending or buckling and partly to the gradual detachment of the
active composition from the metallic portion of the plates; both these effects being
brought about by the expansion of the active material during the use of the battery.
My Invention has for its object the avoidance of these destructive effects firstly by so
enclosing or embedding the active composition in the metallic portion of the plate as
to prevent its falling out and secondly by giving sufficient strength to the plate to
enable it to resist bending or buckling.
In carrying out this my Invention I employ the hardening mixture of oxide of
lead and sulphuric acid for which Letters Patent were granted to me in the year
1882 (No. 4303), and, whilst this mixture is in a pasty condition, I mould it into
small cylinders or rods of convenient length and thickness either by rolling, pressure
through a drawplate or tube, or other convenient means, and I then, whilst they are
still soft, flatten these cylinders on two opposite sides by pressure between two flat
boards or otherwise, so as to make their thickness between the flat sides correspond
with the thickness which it is intended to give to the battery plate.
After these flattened cylinders have become sufficiently hard and dry (which, at
the ordinary temperature, will be the case in about 24 hours, or, if they are exposed
to a gentle heat, in a much shorter time) I place them in rows in a casting mould of
dimensions corresponding to the size of the battery plate required, and at such
distances apart and from the edges of the mould as to give sufficient space for the
quantity of metal necessary to impart adequate strength and rigidity to the plate.
For plates about a foot square, spaces of one tenth of an inch between the cylinders
are sufficient and, for smaller plates, narrower interstices will answer. I then pour
into the mould suitable molten metal, such as lead or an alloy of lead and antimony,
until the interstices between the flattened cylinders are completely filled. In this
way a plate is obtained in which the active material is encased and, except on the flat
sides of the cylinders, overlaid with metal, so that it cannot subsequently fall out
during the charging and discharging of the battery or even when subjected to
considerable rough usage.
Instead of operating in the manner just described, I sometimes carry out my
Invention as follows:-I roll the hardening mixture hereinbefore described, whilst
still soft, into a thin cake which I allow to harden and dry. I then break up this
cake into small fragments and, after sifting out any dust, place these fragments in the

page_text: mould already described so as to fill it or nearly so. I then pour molten metal into
the mould so as to fill up all the interstices. The fragments of active material are
thus embedded in the metal but in such a way that they obtrude at the two surfaces.
The surfaces of plates so prepared may afterwards be planed if desired so as to expose
a larger surface of active material; but this is not necessary. These plates are very
strong and may be subjected to very rough usage with impunity.
It is obvious that these modes of carrying out my Invention may be varied; thus
the hardening mixture may be made into balls or into cheese-shaped masses, but I
have described the methods which I have found to answer the purpose best.
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 :
--
1. The manufacture of the plates of storage batteries or electrical accumulators
by embedding the hardening mixture hereinbefore described in suitable metal by
casting the molten metal around the said mixture substantially as hereinbefore
described.
2. The use in storage batteries or electrical accumulators of plates made sub-
stantially as hereinbefore described.