Improvements in the Construction of Secondary Batteries.
Year: 1888

page_text: Date of Application, 17th Sept., 1888
Complete Specification Left, 17th June, 1889-Accepted, 20th July, 1889
PROVISIONAL SPECIFICATION.
Improvements in the Construction of Secondary Batteries.
SAMUEL ALFRED VARLEY Electrical Engineer of 2 Hamilton Road Highbury Park
London N. in the County of Middlesex do hereby declare the nature of my said
invention to be as follows:-
My invention relates to an improved method of constructing the plates of secondary
batteries by which I obtain relatively to the dimensions of the plates a very large and
active surface. 1 construct the plates as follows. I arrange a number of thin sheets
of lead or a suitable alloy of lead one above the other, separating the metal sheets by
placing preferably a layer of canvas between each of the metal sheets. A sufficient
number of these leaden plates alternated by sheets of canvas having been arranged on
the top of one another, they are placed in a metal mould and with a view to getting
as many plates as possible into the mould they are usually placed under a press and
subjected to pressure.
The mould is strongly constructed so as to be able to withstand a considerable
pressure and forms a box which can be closed with a lid or cover fastened by screw
bolts and forming an air tight joint.
The lid is constructed with a block of metal projecting from the outer side termed
the "projecting block" and a hole is bored through this "projecting block" and
tapped with a screw tap; a metal cylinder having a screw thread cut on one end of
it and some inches along the cylinder screws just freely through the tapped hole of
the "projecting block the other end of this cylinder is usually made square for a
lever handle to fit on to.
The screwed end of the cylinder has a hole drilled up it a few inches and a
second hole bored from the circumference communicates with the hole bored up
the cylinder.
On the top of the "projecting block" there is mounted a metal funnel or hopper
and there is a piece of ordinary steam pipe screwed into a hole bored through the lid
of the mould. This piece of steam pipe is furnished with a stop cock which enables
the air passage between the inside and outside of the mould to be opened or closed
as desired.
After the mould has been filled and the lid has been closed the cylinder is screwed
into the "projecting block" until the hole bored in the side of it is a little below the
surface of the "projecting block" a little lute is then rubbed into the screw thread
so as to make an airtight joint between the screw of the cylinder and the "projecting
block."
The mould is now placed in a bath made preferably of a metallic alloy which melts
at a considerably lower temperature than the fusing point of lead and the stop cock
of the exhaust pipe is opened to let air or moisture in the mould escape.
The metal bath is raised to a temperature of about 400 Fab. and the bath is kept
at this temperature sufficiently long for the whole of the contents in the mould to
have become heated to nearly the same temperature as that of the metal bath.
The exhaust pipe is now connected with an air pump and the interior of the mould
exhausted.
Melting lead or a suitable alloy of lead is now poured into the hopper mounted on
the "projecting block" and surrounding the screwed cylinder.
The screwed cylinder is now unscrewed until the hole bored in the side of it is
raised above the surface of the "projecting block" the melting lead assisted by the
pressure of the atmosphere then rushes through the hole in the screwed cylinder into
the interior of the mould filling it up completely; as soon as this occurs the screwed

page_text: cylinder, by means of a lever handle is forcibly screwed into the mould subjecting the
melting metal to a high pressure and forcing it into all the interstices.
The temperature of the metal bath is now raised to the temperature at which lead
melts which is about 595 Fah.
The effect of raising the interior of the mould to the melting temperature of lead
is to metallically unite the mass throughout more perfectly, and by partly charring
the layers of canvas to generate a certain amount of gas.
The screwed cylinder is now partly unscrewed to create a certain amount of space
in the mould and so enable the gas developed by the carbonization of the canvas to
expand and with a view to allowing further space for expansion the lid of the mould
may be constructed with two or more projecting blocks through which screwed
cylinders work and which create space by being partially unscrewed.
The effect of the expansion of the gas is to develop a number of gas holes
throughout the mass and to render the block of lead or alloy of lead porous, the mould
and its contents is now allowed to cool very slowly and during the cooling the lead
chrystallizes, the mechanical separation of the particles caused by the gas spaces and
semi charred carbon ramifying throughout the block facilitates this chrystallization
and causes it to chrystalize in small chrystals exposing a large surface for oxidation.
When the mould and its contents have become cool the lid of the mould is removed
and the block of lead forced out; this is usually done by means of screws screwed
through the bottom of the mould and which press against a metal plate placed in
the mould previously to putting in the sheets of lead and which rest on the plate.
My invention admits of certain modifications without departing from the leading
principles of the invention which consists in producing in the way hereinbefore
described a mass of lead or lead alloy metallically united throughout but the particles
of which are at the same time mechanically separated to a great extent. For example
the layers of canvas previously to being placed between the sheets of lead or, lead
alloy may be painted over with oxide of lead mixed with water weak glue or any
suitable varnish or the canvas may be dispensed with altogether and the metal sheets
simply painted over with oxide of lead mixed with water or weak glue with a mixture
of wood dust, oxide of lead and glue or a suitable varnish. When I use wood dust
I prefer to heat it to a temperature of about 400 Fah. before mixing it with the glue
to drive off volatile mattor associated with it. When wood dust and glue or oxide
of lead and glue are substituted for the layers of canvas the effects of the heat is to
thoroughly dessicate the glue causing it to contract and to break up into particles
enabling the melting lead under the great pressure to which it is subjected to unite
throughout the mass and the partial charring of the carbonaceous matter of the glue
generates gas which expands, forming air bubbles throughout when the me ling
metal is relieved from pressure by unscrewing the screwed cylinder as previously
hereinbefore described.
The block of lead or lead alloy after it has been removed from the mould is sawn
up into plates and the semi charred matter may be dissolved out of the pores by
soaking the plates in a suitable solvent if thought desirable. To stiffen the lead
plates corrugations may be stamped in them by placing the plates in a suitable shaped
die and applying pressure at the parts to be corrugated.
One two or more lead rods or lead tubes are placed in the corrugations of the
plates and fused to the plates by the process technically known as
" burning the
lead the rods or tubes serve
as connecting rods and when lead tubes are
employed rods of glass ebonite or other suitable material may be placed inside to
stiffen them.
an
The plates are then converted into positive and negative elements by placing them
in a bath of sulphuric acid and water and charging them in alternate directions by
electric current in the well known way first described and adopted by "Plante" for
the construction of storage batteries.
Dated 17th September 1888.

page_text: COMPLETE SPECIFICATION.
Improvements in the Construction of Secondary Batteries.
SAMUEL ALFRED VARLEY, Electrical Engineer of 2 Hamilton Road Highbury
Park London, N., in the County of Middlesex, do hereby declare the nature of my
said 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 relates to an improved-method of constructing the plates of secondary
batteries by which I obtain relatively to the dimensions of the plates a very large
and active surface. I construct the plates as follows-I arrange a number of thin
sheets of lead or a suitable alloy of lead one above the other separating the metal
sheets by placing preferably a layer of canvas between each of the metal sheets. A
sufficient number of these leadeň plates alternated by sheets of canvas having been
arranged on the top of one another, they are placed in a metal mould and with a view
to getting as many plates as possible into the mould they are usually placed under a
press and subjected to pressure.
The mould is strongly constructed so as to be able to withstand a considerable
pressure and forms a box which can be closed with a lid or cover fastened by screw
bolts and forming an air tight joint.
and
The lid is constructed with a block of metal projecting from the outer side termed
the "projecting block" and a hole is bored through the "projecting block'
tapped with a screw tap; a metal cylinder having a screw thread cut on one end of
it and some inches along the cylinder screws just freely through the tapped hole of
the " projecting block" the other end of this cylinder is usually made square for a
lever handle to fit on to.
The screwed end of the cylinder has a hole drilled up it a few inches and a
second hole bored from the circumference communicates with the 'hole bored up
the cylinder.
On the top of the "projecting block" there is mounted a metal funnel or hopper
and there is a piece of ordinary steam pipe screwed into a hole bored through the lid
of the mould. This piece of steam pipe is furnished with a stop cock which
enables the air passage between the inside and outside of the mould to be opened
or closed as desired.
"
After the mould has been filled and the lid has been closed the cylinder is screwed
into the "projecting block" until the hole bored in the side of it is a little below the
surface of the "projecting block a little lute is then rubbed into the screw thread
so as to make an airtight joint between the screw of the cylinder and the "projecting
block."
The mould is now placed in a bath made preferably of a metallic alloy which melts
at a considerably lower temperature than the fusing point of lead and the stop cock of
the exhaust pipe is opened to let air or moisture in the mould escape.
The metal bath is raised to a temperature of about 400 Fah. and the bath is kept
at this temperature sufficiently long for the whole of the contents in the mould to have
become heated to nearly the same temperature as that of the metal bath.
The exhaust pipe is now connected with an air pump and the interior of the mould
exhausted.
Melting lead or a suitable alloy of lead is now poured into the hopper mounted on
the "projecting block" and surrounding the screwed cylinder.
The screwed cylinder is now unscrewed until the hole bored in the side of it is
raised above the surface of the "projecting block" the melting lead assisted by the
pressure of the atmosphere then rushes through the hole in the screwed cylinder into
the interior of the mould filling it up completely. As soon as this occurs the screwed
cylinder by means of a lever handle is forcibly screwed into the mould subjecting the
melting metal to a high pressure and forcing it into all the interstices.
The temperature of the metal bath is now raised to the temperature at which the
lead melts which is about 595 Fah.

page_text: The effect of raising the interior of the mould to the melting temperature of lead
is to metallically unite the mass throughout more perfectly and by partially charring
the layers of canvas to generate a certain amount of gas.
The screwed cylinder is now partly unscrewed to create a certain amount of space
in the mould, and so enable the gas developed by the carbonization of the canvas to
expand and with a view to allowing further space for expansion the lid of the mould
may be constructed with two or more projecting blocks through which screwed
cylinders work and which create space by being partially unscrewed.
The effect of the expansion of the gas is to develope a number of gas holes
throughout the mass and to render the block of lead or alloy of lead porous, the
mould and its contents is now allowed to cool very slowly and during the cooling
the lead chrystallizes, the mechanical separation of the particles caused by the gas
spaces and semi-charred carbon ramifying throughout the block facilitates this
chrystallization and causes it to chrystalize in small chrystals exposing a large surface
for oxidation.
When the mould and its contents have become cool the lid of the mould is removed
and the block of lead forced out this is usually done by means of screws screwed
through the bottom of the mould and which press against a metal plate placed in the
mould previously to putting in the sheets of lead and which rest on the plate.
My invention admits of certain modification without departing from the leading
principles of the invention which consist in producing in the way herein before
described a mass of lead or lead alloy metallically united throughout but the particles
of which are at the same time mechanically separated to a great extent.
For example
the layers of canvas previously to being placed between the sheets of lead or lead alloy
may be painted over with oxide of lead mixed with water weak glue or any suitable
varnish or the canvas may be dispensed with altogether and the metal sheets simply
painted over with oxide of lead mixed with water or weak glue with a mixture of
wood dust, oxide of lead and glue or a suitable varnish. When I use wood dust
I prefer to heat it to a temperature of about 400 Fah. before mixing it with the glue
to drive off volatile matter associated with it. When wood dust and glue or oxide of
lead and glue are substituted for the layers of canvas the effect of the heat is to
thoroughly dessicate the glue causing it to contract and to break up into particles
enabling the melting lead under the great pressure to which it is subjected to unite
throughout the mass and the partial charring of the carbonaceous matter of the glue
generates gas which expands forming air bubbles throughout, when the melting metal
is relieved from pressure by unscrewing the screwed cylinder as previously herein-
before described.
The block of lead or lead alloy after it has been removed from the mould is
sawn up into plates and the semi charred matter may be dissolved out of the
pores by soaking the plates in a suitable solvent if thought desirable. To stiffen
the lead plates corrugations may be stamped in them by placing the plates in a
suitable shaped die and applying pressure at the parts to be corrugated one two
or more lead rods or lead tubes are placed in the corrugations of the plates and
fused to the plates by the process technically known as burning the lead the
rods or tubes serve as connecting rods and when lead tubes are employed rods of glass
ebonite or other suitable material may be placed inside to stiffen them.
"
"
an
The plates are then converted into positive and negative elements by placing them
in a bath of sulphuric acid and water and charging them in alternate directions by
electric current in the well known way first described and adopted by "Plante" for
the construction of storage batteries.
And in order that my invention may be more fully understood I will proceed to
describe the drawings hereunto annexed.

page_text: with oxide of lead are placed and subjected to the treatment already hereinbefore
described A is the chamber L is the lid which closes the top of the chamber A
forming an airtight joint and fastened by screws S as represented on the drawing as
screwdriver screws but in practice screw bolts and nuts are generally adopted.
B is the projecting block cast in one piece with and forming part of the lid.
C is the screwed cylinder working through the projecting block B.
P is a passage bored up the lower end of screwed cylinder C through which the
melting lead which is poured into the funnel or hopper F rushes into the interior of
chamber A when the cylinder C is partly unscrewed so as to bring the horizontal
opening O above the surface of the projecting block B.
D is a metal plate placed at the bottom of the chamber A on which the lead sheets
rest E are screws passing through the bottom of the chamber A and which enable
the plate D to be forced upwards so as to loosen the metal block and so facilitate its
removal.
H is a piece of steam piping which can be opened or closed by the cock I.
Having now described the nature of the said Invention and the manner in which
the same is to be performed, I would have it understood I do not confine myself to
the precise details herein shewn and described but what I do claim is
First. Producing a block of lead or a suitable alloy of lead metallically united in
one solid mass but at the same time intimately mixed throughout with oxide of lead
or other matter and having small interstices and which can be afterwards sawn up
into plates for the construction of secondary batteries substantially as described.
2ndly. I claim the producing such blocks by placing them in an airtight chamber
and subjecting them to pressure when the lead or a suitable alloy of lead is in a melting
condition substantially as herein before described.
June 17th 1889.
SAMUEL ALFRED VARLEY.