IN SECONDARY BATTERIES
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by the said James Pitkin at the Office
of the Commissioners of Patents on the 13th December 1881.
JAMES PITKIN, of Clerkenwell, in the County of Middlesex.
IN SECONDARY BATTERIES."
"IMPROVEMENTS
My Invention relates to improvements in secondary batteries or accumulators,
and its object is to enable a greater amount of energy to be stored in, and conse-
quently a greater quantity of electricity to be furnished by, electrodes of given
dimensions, and at same time to greatly decrease the weight of the electrodes
as compared with that of those formed of plates of lead as usually employed in
batteries of this description.
My Invention consists in forming the electrodes of a mass of very thin turnings
or shavings of lead or strips, shreds, or pieces of lead foil or highly laminated sheets
of lead in a crumpled condition packed in suitable open frames preferably of wood
or ebonite, and each having a covering of felt, flannel, or other suitable porous
material stretched over it on each side to retain the lead in place and allow it to
be acted on by the acidulated liquid in which the electrode is immersed.
The electrode thus constituted is connected with the terminals or connecting
strips used for joining up the electrodes to form a battery by means of a rod of
lead, one end of which is flattened and divided into a number of narrow leading
strips or branches which are distributed uniformly through the mass of the
electrode. When an electric current from any source is passed through two such
elements connected together and immersed in acidulated water in the usual way,
the one element becomes peroxidised and when the direction of the current is
reversed the other element becomes peroxidised and the first one becomes reduced
to the state of spongy metallic lead.
My Invention also consists in the employment in combination with the shavings,
turnings, or other shreds or thin pieces of lead of red lead, litharge, or other lead
oxide, or a salt of lead mixed in a powdered or other condition with the said
shavings, turnings or other shreds of lead, and enclosed in a frame as above
described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James Pitkin in the Great Seal Patent Office on the 13th June
1882.
JAMES PITKIN, of Clerkenwell, in the County of Middlesex.
IN SECONDARY BATTERIES."
"IMPROVEMENTS
My Invention relates to improvements in secondary batteries or accumulators
for the electro chemical storage of energy and its object is to enable an equal or
greater amount of energy to be stored in less time, in electrodes of equal
dimensions to, but of much less weight than those in which solid plates of lead are
used.
My Invention consists in forming each electrode of a mass of very thin turnings
or shavings of lead (or strips, shreds, or pieces of lead foil, or of highly laminated
sheets of lead) in a crumpled and entangled condition packed in an open frame of
wood or ebonite-and-enclosed-in-a-covering-of-felt, flannel,-or-other-suitable-porous-
fabric stretched over it on each side to retain the lead in place and allow it to be
acted on by the electrolytic liquid. The electrode thus constituted is connected
with the terminals or connecting strips used for joining up the electrodes to form a
battery by means preferably of a rod of lead flattened and cut or divided into a
number of narrow leading strips or branches which are distributed uniformly
through the mass of the electrode. This method of branching the conductor avoids
the use of soldered joints and the local action resulting therefrom. The battery is
formed by passing an electric current through it first in the one direction and then
in the other in the usual way whereby the one element becomes peroxidised and
the other becomes reduced to the state of spongy lead.
In the accompanying Drawings I have represented an example of my
Invention.
Figure represents a face view, and Figure 2 an edge view of one of my electrodes,
part of the frame and covering material being removed to show the interior.
A is an open frame of wood, ebonite, or other nonconducting material. B is a
mass of very thin turnings or shavings of lead, or strips or pieces of lead foil or of
other very thin sheets of lead packed into the frame A and retained therein by
coverings CC of felt or flannel stretched over each side of the frame A and secured
by wood pegs c driven through the overlapping edges of the two coverings C C or
by sewing, cementing or otherwise.
I prefer to use very thin lead turnings obtained by turning down a cylinder of
lead in a self acting lathe, the tool being preferably so formed and held as to turn
off shavings of a curly or spiral and wrinkled form as they pack less densely in the
frame. D is a rod of lead passing through the frame A and flattened out to a
broad end which is slit or divided into a number of leading strips or branches d
distributed uniformly through the electrode.
"
Having described the nature of my Invention for "Improvements in Secondary
Batteries and the manner of performing the same, I declare that what I claim
as my Invention to be protected by the herein before in part recited Letters
Patent is,
1st. An electrode of a secondary battery composed of a mass of very thin
turnings, shavings, shreds, strips, or pieces of lead contained in a suitable receptacle
or covering. substantially as herein specified.
2nd. The combination of the frame A, the coverings C, the rod D split or divided
into branches d and the mass of lead turnings or shavings or other thin shreds,
strips, or pieces of lead B substantially as and for the purpose herein described and
shown in the Drawing.

page_text: 3rd. In a secondary battery the employment of an open frame having a covering
fabric stretched over each side of it as herein shown and described as a means of
holding the lead or lead compound composing the electrode.
In witness whereof I the said James Pitkin have hereunto set my hand and
seal this Ninth day of June A.D. 1882.
JAMES FITKIN. (L.S.)