Improvements in Elements for Secondary Batteries.
Year: 1891

page_text: Date of Application, 17th Oct., 1891
Complete Specification Left, 14th July, 1892-Accepted, 3rd Sept., 1892
PROVISIONAL SPECIFICATION.
Improvements in Elements for Secondary Batteries.
We THE MINING AND GENERAL ELECTRIC LAMP COMPANY LIMITED of
11 Abchurch Lane in the City of Londou and Joв THOMAS NIBLETT of
64 Millbank Street in the City of Westminster, Electrical Engineer, do hereby
declare the nature of this invention to be as follows:-
This invention relates to improvements in the supports or holders for the active
material in voltaic cells chiefly of the accumulator or secondary type.
In secondary or storage cells the usual method of constructing the elements or
electrodes is to either cast a rigid metallic support grid or frame of lead or any
alloy of lead and then apply some material which is afterwards converted into active
material by a process of electrolysis or to mould or compress masses or slabs of
the material ultimately to become active into the form of a plate or electrode of
any suitable shape or according to a third method supports have been formed
of woven copper wire which are protected from electrolytic action by a coating of
lead or lead alloy. In the first case the electrical energy is collected or conducted
away by the metal frame or grid itself and in the second case conducting strips are
clamped to the compressed or solidified mass of active material for conducting away
the electrical energy while in the third case the mesh itself is used as a conductor.
In this last case owing to the difficulty of obtaining a perfect coating of the lead
which is used for the purpose of protecting the copper from electrolytic action and
the dissolving effect of the electrolyte some difficulty has been experienced.
According to this invention in place of the supports as herein before referred to
as a means for carrying the active material a network or woven mesh of lead,
lead and antimony or other unoxidizable material or materials capable of being
woven into meshes or network is employed. To give the network (or mesh) the
requisite mechanical strength the network is surrounded by a rim of metal or other
rigid substance or the network or mesh may be mounted on a metallic plate or
other suitable support. To make better contact and to prevent the formation of
sulphate or other inert salts between the network and the active material the said
network or supporting plate and network may be coated by any suitable means
with gold, platinum or other suitable metal which is not easily affected by electro-
lysis or by the electrolyte.
The network may be composed partly of lead or other unoxidizable metal and
partly of asbestos or other material not affected by the electrolyte whereby coherence
of the active material to the support is increased and the weight is considerably
reduced. This form of support may be used for both positive and negative
elements.
1001
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Elements for Secondary Batteries.
We THE MINING AND GENERAL ELECTRIC LAMP COMPANY LIMITED (now
re-constructed and named The Lithanode and General Electric Company Limited).
of 11 Abchurch Lane in the City of London and JOB THOMAS NIBLETT of
64 Millbank Street in the City of Westminster Electrical Engineer. do hereby.
D
077

page_text: 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 consists of improvements in elements for secondary batteries and
relates more especially to the supports or holders for the active material of such
elements.
In secondary or storage batteries the usual method of constructing the elements
or electrodes hitherto adopted is to cast a rigid metallic support grid or frame of
lead or alloy of lead and then apply some material which is afterwards converted
into active material by electrolysis. Masses or slabs of the material ultimately to
become active have also been moulded or compressed into the form of a plate or
electrode of any suitable shape.
Supports have also been formed of woven copper wire protected from electro-
lytic action by a coating of lead or lead alloy. In the first case the electrical
energy is collected or conducted away by the metal frame or grid itself and in the
second case conducting strips are clamped to the compressed or solidified mass of
active material for conducting away the electrical energy while in the third case
the mesh itself is used as a conductor.
In this last case owing to the difficulty of obtaining a perfect coating of the lead
or lead alloy which is used for the purpose of protecting the copper from electro-
lytic action and the dissolving effect of the electrolyte difficulty has been experienced
in producing an efficient electrode.
According to this invention in place of the supports as hereinbefore referred to
as a means for carrying the active material a net-work or woven mesh of lead or of
lead alloy such as an alloy of lead and antimony alone or in conjunction with other
material or materials not oxidizable by the electrolyte and capable of being woven
into meshes or net-work is employed. To give the net-work (or mesh) the requisite
mechanical strength the net work may be surrounded by a rim of metal or other
rigid substance or the net work or mesh may be mounted on a metallic plate or
equivalent support or the plate may be situated between two such net works or
meshes.
The material to be rendered active is applied to this net work or mesh or net
works or meshes.
To make better contact and to prevent the formation of sulphate or other inert
or deleterious salts between the net work and the active material the said net work,
or supporting plate and net work, may be coated by any suitable means with gold,
platinum or other suitable metal which is not easily affected by electrolysis or by
the electrolyte. This coating may be effected as described in the Specification of
Letters Patent No. 9629 of 1891 granted to Desmond Gerald Fitz Gerald.
The net work may be composed partly of lead or other non-oxidizable metal
and partly of asbestos or other material not affected by the electrolyte (such as
hempen cord for instance) whereby coherence of the active material to the support
is increased and the weight is considerably reduced. For instance the mesh may
be made of wires of lead or lead alloy in one direction and of cords or strips of the
asbestos or other material in the other direction.
In the accompanying drawings we have illustrated forms of supports made
according to our invention.
Fig. 1 is a side elevation of a support made by interweaving the wires a and b
of lead or lead alloy into a mesh. There may be one, two or more, layers of such
mesh in each support.
Fig. 2 is a transverse section of an arrangement wherein meshes are made of
the wires a and b of lead or lead alloy and between these is the plate c which may
be flat or corrugated as shewn and it may be perforated or unperforated.
The meshes and plate c are secured to the frame d which may be of lead or lead
alloy.to which is soldered the conducting tang d.
Fig. 3 is a section shewing a flat plate c' between the two meshes and

page_text: Fig. 4 shews one mesh only at one side of the plate c³ which may as aforesaid be
flat or corrugated and perforated or unperforated.
This form of support may be made by making the plate ca little larger than the
sheet of mesh and turning the edges of the plate over the edges of the mesh. The
aforesaid supports may be used for both positive and negative electrodes.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In or for elements for secondary batteries supports or holders made of, or in
part made of, a mesh or meshes of wire of lead or lead alloy substantially as
hereinbefore described.
2. In or for elements for secondary batteries supports or holders made of a mesh
or meshes of wire of lead or lead alloy in combination with a supporting plate
substantially as hereinbefore described.
3. In or for elements for secondary batteries supports or holders made of, or in
part made of, a mesh or meshes composed partly of wire of lead or lead alloy
and partly of asbestos or equivalent material substantially as hereinbefore
described.
4. In or for elements for secondary batteries supports or holders constructed as
herein before described and shewn in the several figures of the accompanying
drawings.
Dated this 11th of I-11000
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.