Improvements in Secondary Batteries.
Year: 1892

page_text: L'ate of Application (in United Kingdom), 14th Sept., 1892
Complete Specification Left, 14th Sept., 1892-Accepted, 22nd Oct., 1892
COMPLETE SPECIFICATION.
Improvements in Secondary Batteries.
I, WILLIAM MAIN, of 299 Jeffersons Avenue, City of Brooklyn, County of
Kings, State of New York, United States of America, Electrical Engineer, 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 secondary batteries and the construction of cells and
plates designed therefor. The invention has been made in connection with
secondary batteries of that class covered by my prior Letters Patent No. 4303 of
1887 and 6112 of 1889, the latter granted to Philip Arthur Newton for an
invention communicated by myself; and the invention consists in part of improve-
ments thereon. Reference is made, therefore, to these Patents for a full statement
of the battery action, and the special construction and function of certain parts, but
it will be understood that the improvements forming the broad invention in the
present case are applicable also in many other batteries.
In the Patents above referred to, there have been described oxygen electrodes
consisting of compound laminated plates of lead or other suitable material, & plates
of conducting material, the compound plate being provided with numerous transverse
perforations, and preferably with graphite or other conducting material between the
laminae, and hydrogen electrodes consisting of plates of copper or other electrically
conductive material forming supports for the active material, consisting of zinc and
mercury, the copper supports being arranged horizontally with the zinc and
mercury contained in pockets thereon.
I have discovered that the horizontal position of the supports is not necessary,
but that mercury may be drawn to the top edge of a vertical plate of copper or
other material having an affinity for mercury, in quantities sufficient to form an
amalgam with the zine deposited thereon by electrolytic action during the charge
of the cell, and by a construction employing a vertical support, I am able to attain
certain important advantages over constructions employing a horizontal support,
especially the following:
With the supports and plates forming the oxygen electrode arranged in a
horizontal position and alternated, the mercury is liable to drop from the copper to
the lead, amalgamating the latter. It is found, also, that deposits of zinc sometimes
form about the edges of the support, and depend therefrom, so as to reach the lead
plates and short-circuit the cell, and when a series of supports are used, the removal
of these projections involves considerable labour.
It is found that the mercury is uniformly distributed over the entire surface of
the vertical support, and that the danger of the mercury reaching the lead plates is
avoided, any mercury passing from the copper support falling directly to the bottom
of the cell. Moreover, there is little tendency to form zinc projections extending
towards the plates from the supports, as such projections must form horizontally,
and, moreover, such projections may readily be removed from the top of the cell,

page_text: by passing a rod down between the plates, and moving it to and fro, so as to break
them off. If a glass cell be used, as is preferable, such projections can readily be
seen and removed. Moreover, by the use of a vertical support, the amount of zinc
and mercury required is reduced, as with the horizontal arrangement an inde-
pendent source of mercury and zinc is required for each support, while, with the
vertical arrangement, a common source of zinc and mercury for all the supports
may be used, and a very small supply of these materials thus answers for the entire
battery.
The vertical support may be of any suitable material conductive of electricity,
and which is inactive in the battery, and has an affinity for mercury, but is not
penetrated thereby. I prefer, however, to use thin copper plates, as copper has
high electrical conductivity, and is not acted on chemically in the presence of zinc.
By inactive material, I mean one which acts as a mere surface vehicle for the active
material, without taking part in the reactions of the battery. By a material having
an affinity for mercury, I mean one which is wet by mercury, so that the mercury
spreads upward and over the surface from one part of the support to another. By
material which is not penetrated by mercury, I mean one upon the surface of
which mercury or an amalgam is supported without the mercury passing into or
combining with the body of the material, so as to cause disintegration of the
same.
The supports may be smooth, or provided with roughened surfaces, or small
perforations, and fairly good results be obtained, but the deposit tends to scale off,
and the support is preferably perforated with quite large holes, which I have found
much preferable to small holes, or to roughening the sides of the support, as the
amalgam is deposited through the holes, so as to grip upon the rear sides of the
support, the scaling of the deposited zinc almalgam thus being prevented. These
large holes also have a special function in connection with my preferred form of
zinc supply, by which I am enabled to avoid a difficulty previously found in the
commercial use of secondary batteries, and obtain an important advantage, as
follows:-
In the commercial handling of cells, they must be shipped without acid in them,
and it is undesirable to ship the copper support with any considerable deposit of
amalgam thereon, as it is liable to crumble off from the jarring and rough handling
received, especially during a railroad transportation. It has heretofore been
necessary, therefore, when cells were unpacked and set up, to put sulphate of zinc
into the fluid, and give the cells a prolonged charging, for the purpose of providing
them with a good supply of metallic zinc.
I avoid this necessity by the use of sheets of amalgamated zinc, as a zinc supply
for starting the battery. Any suitable construction and arrangement of the zinc
plates and supporting parts may be used, but I prefer to make the copper supports
double, by arranging them in pairs, the two supports of each pair being placed
close together, and to place a zinc plate between each pair of such supports. The
electrolytically deposited amalgam is preferred, but the ordinary sheet zine amal-
gamated answers very well, and, used as described, enables the cell to be put into
use at once. The copper supports are usually amalgamated at the start, as a result
of this construction, and the cell can be shipped without liquid, but with a supply
of amalgam to commence operations with. If the oxygen pole piece is charged,
and zinc present in sufficient quantity on the hydrogen electrode, à good discharge
can be obtained from the cell when first set up.
Upon recharge, the zinc, which has passed into solution, will be redeposited over
the upper surface. The large holes in the supports allow action to take place
freely between the zine on one side and the lead peroxide on the other, as the zinc
would otherwise be entirely partitioned off. The holes also render the reverse
sides of the supports available for the retention of amalgam and active during
discharge, the active surface thus being increased.
While the construction described, employing double perforated supports and
sheets of amalgamated zinc supported loosely between them, is preferred, other

page_text: constructions may be used. Thus, I may rivet the sheets onto the supports, so as
to form a single construction therewith, or it may be found that a paste of zinc
amalgam pressed onto the surface of, and into the interstice of a support provided
with small perforations, or having a roughened surface, will answer the purpose.
The oxygen electrode consists preferably of vertical compound plates, formed,
as described in the Patents above referred to, of a series of thin sheets of lead, or
other suitable material, and thicker sheets of conductive material, all provided with
numerous perforations, and secured together by rivets of suitable material. It will
be understood, however, that this electrode may be of any other suitable construction,
and either of laminated or grid form.
In the use of laminated plates, it is found that the laminae are increased in
thickness by oxidation during the battery action, the sides of the plate being forced
out, thus weakening and injuring the electrode. I avoid this difficulty by providing
space between the laminae for this increase of thickness, and I attain this result by
my improved process of making the plate in which I coat the laminae with soluble
material, and dissolve out this material. The soluble material may be dissolved
out after the plate is completed, and before placing it in the battery acid, but I
preferably use a soluble material which is not injurious to the battery, so that the
material may be dissolved out in the battery acid, and by the use of material
containing zinc or other soluble material which is needed in the battery, I am able
to make the soluble material perform two functions.
Any suitable material may be used either alone or mixed with other materials,
but I prefer to use a mixture of oxide of zinc and graphite, the oxide of zinc
dissolving out in the battery fluid, and passing to the hydrogen electrode, where it
is required, while the graphite adheres to the surfaces of the laminae, so as to
increase their conductivity. The oxide of zinc thus performs the double function
above described, that is, of providing space between the laminae for their increase
in thickness, and at the same time being of use in the battery. If, however, the
character of the battery and laminated electrode is such, that a deposit of zinc is
not required, other suitable soluble materials not injurious in the battery may be
used, such as salts of alumina, or sulphite of magnesia.
Sugar or salt, also, may be used, but these should be dissolved out before placing
the electrode in the battery, as they interfere with the battery action. In place of
graphite, also, it is evident that other electrically-conductive material may be used,
but graphite is preferred.
The mercury supply may be placed in any part of the cell with surface contact
between the mercury and some part of the copper supports the mercury spreading
rapidly over the surface of the supports, this action being aided probably by the
formation of the zinc deposit. I prefer, however, to place the deposit in the
bottom of the cell, with the lower end of the supports in contact therewith, any
mercury from the plates thus passing directly to the supply. An efficient supply
may readily be formed by pouring a little mercury into the cell. The support
may be made of material of such porosity as to retain the mercury, thus forming
the mercury supply; or a plate perforated with small holes, or having roughened
surfaces, may be found to answer the purpose. A supply of metallic mercury
may be provided, also, by the use of a soluble salt of mercury, in beginning the
operation of the battery, this yielding metallic mercury on charge.
Any suitable electrolyte may be used in the cell, such as ordinary dilute
sulphuric acid, or dilute sulphuric acid containing a solution of zinc, or a solution
of mercury, or both. I do not confine myself to any particular electrolyte.
In connection with my cell, I have devised, also, an improved connector or clamp
for electric conductors, which forms in itself a part of my invention. It is
important that the conductivity between electric conductors clamped together,
should be as high as possible, and that this conductivity should be maintained
unimpaired by corrosion due to the battery acids. The screw clamps heretofore
made of hard rubber are not affected by corrosion, but are expensive, brittle, and,
moreover, are not conductive, so that the conduction of terminals forced together

page_text: .
Brass
thereby, depends upon the single faces of the terminals in direct contact.
has been used, but while this is conductive, it is corroded by the battery acids.
I provide an improved connector which is conductive throughout and non-
corrodable, so that the entire surfaces of the terminals form contact surfaces, and,
moreover, the contact is not affected substantially by corrosion due to the battery
action. In my improved clamp, I use lead, preferably alloyed with antimony, or
some similar non-corrodable metal, to harden it, and the key is of the same
material. The connector consists of a collar, the opening in which is of suitable
form to receive the parts which are to be clamped together and provide large
surfaces of contact, and the key is wedge shaped, and corresponds in form to the
parts which are to be engaged thereby, so as to clamp them securely together.
This conductor may be used for clamping tagether two round or flat conductors, or
clamping a conductor to the connector, or to any other part, the form of the collar
and wedge being varied as required.
By my invention I provide a very simple, cheap, and convenient conductor which
provides for high conductivity between the parts connected thereby, and by which
the conductivity is maintained substantially unimpaired by the action of the
battery acids. The wedge, moreover, may be put in and taken out more readily
than a screw, which is liable to stick, and a screw of sufficient strength cannot be
made out of lead alloy, and the contact surface of a screw point is small.
The terminals used with my cell may be of any construction, and may consist
simply of a conductor of lead or other non-corrodable material. If lead be used,
however, it will be necessary to use a quite large terminal for securing the
conductivity required. I prefer, therefore, to use terminals consisting of a core
of copper and a lead covering, the copper core securing the conductivity required,
while the lead covering prevents corrosion, a small efficient terminal being thus
formed.
Referring now to the accompanying drawings, in which I have illustrated my
invention as embodied in a cell of the preferred form,-
Fig. 1 is a perspective view of the cell with the casing removed.
Fig. 2 is a vertical section transverse to the electrodes.
Figs.
and 4 are sections respectively on lines 3 and 4 of Fig. 2.
Fig. 5 is a detail section of my improved connector.
Fig. 6 is a plan of the same.
Fig. 7 is a plan view showing the connector applied in connection with two flat
terminals.
A is the cell casing, which may be of any suitable material, but is preferably of
glass, so as to allow free inspection of the parts contained therein. B is the
oxygen electrode, which, in the form shewn, consists of a series of compound
laminated plates arranged vertically. The structure of these compound laminated
plates is preferably substantially the same as that of the patents above referred to,
consisting of a series of thin laminae, 1, of suitable material, preferably lead,
separated by thicker sheets or plates, 2, of suitable conducting material, all being
secured together by rivets, 3, of the same material as the laminae, and provided
with a large number of perforations, as shown at 4. In constructing these
compound plates, however, I prefer to provide space for the expansion of the
laminae due to oxidation in the battery, by coating them with soluble material as
above described, which is removed in solution, either in the battery fluid, or before
putting the plates in the battery, graphite or other suitable conducting material
being preferably mixed therewith, or otherwise applied to the laminae. The
compound plates B are connected together to form the oxygen electrode by a
yoke C, to which the terminals 5 are connected in the usual manner, and are
supported within the battery by vertical separators D, consisting of plates of hard
rubber or other suitable insulating non-corrodable material, which are provided
with slots through which the ends of the plates are passed. The compound plates
are thus supported at the proper distance from the bottom of the cell, and the
entire structure of oxygen electrode and separators is readily introduced into, and

page_text: removed from the cell by the yoke C connecting the plates B. The vertical
support for the deposit forming the active hydrogen electrode, consists, in the
preferred form shown, of thin sheets of copper E, which are shown as bent to
U shape, so as to form double plates on either side of each of the compound
plates B, the doubled copper plates being rivetted together, with one or more
washers, 6, between the plates, so as to provide space between them for a thin
sheet of amalgamated zinc G, by which a supply of zinc is provided for starting
the battery as above described, the sheet of zinc G being slipped down between
the doubled copper plates, and supported above the bottom of the cell by a central
rivet in the copper plates, as shown in Fig. 4. It will be understood, however,
that any other suitable construction of the copper plates, and means for supporting
the zinc plate G, may be employed.
As above stated, the copper plates E forming the supports, are preferably
perforated with a series of quite large holes, these holes being preferably of one
fourth to one half an inch in diameter. By the use of these large holes, I find
that the deposit forms through the thiu copper plates, so as to grip upon the inner
edges thereof, thus affording a strong hold for the amalgam. These holes also
provide free access of the battery fluid to the amalgamated zinc sheets G between
the copper supports. The copper supports are connected together by the rivetting
of the adjacent plates, so as to form, with the deposit, the hydrogen electrode, and
the terminals 8 are connected to the end plates in the usual manner. It is
apparent that all the parts of the cell may be readily introduced into, and removed
from the liquid together, the copper supports E carrying with them, on removal,
the oxygen electrodes B and separators D, the latter resting upon the horizontal
plates of the copper supports at the base of the cell.
As above stated, the mercury supply may be in any part of the cell in surface
contact with some part of the copper support, but is preferably formed by pouring
a little mercury into the cell, and any suitable electrolyte may be used.
It will
be understood that a cell may be formed having only one support and one oxygen
plate, and that in batteries employing a number of cells, the electrodes are
arranged in pairs, and the lugs or terminals of the same poles connected.
With the construction described, any suitable means may be used for connecting
the terminals 5, 8, from the oxygen and hydrogen electrodes. As above stated,
however, I have devised an improved connector which is preferably used, and
which forms in itself a part of the present invention. This connector consists of
a collar 9, provided with an opening of suitable form to receive the terminals 5, 8,
this opening being preferably concave at the ends, when used with round conductors,
so as to afford large contact surfaces therewith, and a wedge 10, which is also
formed preferably so as to engage the terminal with which it is in contact, and the
inner wall of the collar, by large surfaces. It will be seen by an inspection of
Figs. 5 and 6, that the terminals 5, 8 may be firmly secured in the collar 9, by
forcing in the wedge 10, and with the wedge extended through the collar 9, as
shown, it may readily be removed by pressing up upon the smaller end, as by
means of a pair of pinchers engaging the collar and this end of the wedge.
While in Figs. 5 and 6 I have shown my connector applied to join two round
terminals, it will be understood that my connector is applicable also to terminals
of other form, and the collar 9 may form itself one of the terminals, and the wedge
be used for joining any round or flat terminal thereto, the form of the collar and
wedge being varied accordingly. Thus, in Fig. 7, I have shown my connector
used for uniting two flat terminals 11, 12, the form of the collar 13 and wedge 14
being varied as required. The terminals 5, 8, as above stated, may be of any
suitable construction, but consist preferably of a copper core and lead covering..
It will be understood that I have shown but one of many constructions in which
my invention may be embodied, and that the form and arrangement of the
electrodes and other parts may be varied widely without departing from my inven
tion, and that the improvements forming the broad invention may be applied in

page_text: batteries employing different materials, and of different action from that described
and shown.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A secondary battery cell having a hydrogen electrode consisting of a vertical
conductive support inactive in the liquid, having an affinity for, but not penetrated
by, mercury, and a coating of zinc and mercury on the surface of the support
forming the active material, substantially as described.
2. A secondary battery cell having a hydrogen electrode consisting of a vertical
conductive support inactive in the liquid, having an affinity for, but not penetrated
by, mercury, and covered with a deposit of zinc, the cell containing a supply of
mercury, substantially as described.
3. A secondary battery cell having a hydrogen electrode consisting of a vertical
conductive support inactive in the liquid, having an affinity for, but not penetrated
by, mercury, and covered with a deposit of zinc, and a supply of mercury in the
bottom of the cell in contact with the support, substantially as described.
4. A secondary battery cell having a hydrogen electrode consisting of a series
of vertical conductive supports inactive in the liquid, having an affinity for, but
not penetrated by, mercury, and covered with a deposit of zinc, the cell containing
a supply of mercury, substantially as described.
5. A. secondary battery cell having a hydrogen electrode consisting of a series
of vertical conductive supports inactive in the liquid, having an affinity for, but not
penetrated by, mercury, and covered with a deposit of zinc, the cell containing a
supply of mercury, and an oxygen electrode consisting of a series of vertical plates,
substantially as described.
6. A secondary battery cell having a hydrogen electrode consisting of a vertical
conductive support inactive in the liquid, and having an affinity for, but not
penetrated by, mercury, and a supply of zinc and mercury, whereby a deposit of
zinc is formed on the support, and the deposit amalgamated by capillary action,
substantially as described.
7. A secondary battary cell having a hydrogen electrode consisting of a vertical
support inactive in the liquid, and having an affinity for, but not penetrated by,
mercury, an oxygen electrode of lead, and a supply of zinc and mercury, substantially
as described.
8. A secondary battery cell having a hydrogen electrode consisting of a vertical
conductive support inactive in the liquid, and having an affinity for, but not
penetrated by, mercury, a supply of mercury, and one or more sheets of amalga-
mated zinc forming a zinc supply, substantially as described.
9. A secondary battery cell having a hydrogen electrode consisting of a vertical
perforated conductive support inactive in the liquid, and having an affinity for, but
not penetrated by, mercury, and a supply of zinc and mercury, substantially as
described.
10. A secondary battery cell having a hydrogen electrode consisting of a series
of vertical, perforated conductive supports arranged in pairs, said supports being
inactive in the liquid, and having an affinity for, but not penetrated by, mercury,
a supply of mercury, and sheets of amalgamated zinc between the pairs of supports
forming a zinc supply, substantially as described.
11. A secondary battery cell having a hydrogen electrode consisting of a vertical
copper support, and a coating of zinc and mercury on the surface of the support
forming the active material, substantially as described.
12. A secondary battery cell having a hydrogen electrode consisting of a vertical
copper support covered with a deposit of zinc, the cell containing a supply of
mercury, substantially as described.
13. A secondary battery cell having a hydrogen electrode consisting of a series

page_text: of vertical copper supports covered with a deposit of zinc, the cell containing a
supply of mercury, substantially as described.
14. A secondary battery cell having a hydrogen electrode consisting of a series
of vertical perforated copper supports covered with a deposit of zinc, the cell con-
taining a supply of mercury, substantially as described.
15. A secondary battery cell having a hydrogen electrode consisting of a series
of vertical copper supports covered with a deposit of zinc, the cell containing a
supply of mercury, and an oxygen electrode consisting of a series of vertical plates
substantially as described.
16. A secondary battery cell having a hydrogen electrode consisting of a vertical
copper support, an oxygen electrode of lead, and a supply of zinc and mercury,
substantially as described.
17. A secondary battery cell having a hydrogen electrode consisting of a vertical
copper support, a supply of mercury, and one or more sheets of amalgamated zinc
forming a zinc supply, substantially as described.
and
18. A secondary battery cell having a hydrogen electrode consisting of a series
of vertical perforated copper supports arranged in pairs, a supply of mercury,
a sheet of amalgamated zinc between each pair of supports, substantially as
described.
19. A secondary battery cell having a hydrogen electrode consisting of a vertical
perforated conductive support inactive in the liquid, and an electro deposit of zinc
thereon, substantially as described.
20. A secondary battery cell having an element consisting of a vertical copper
plate supporting electro deposited zinc, substantially as described.
21. A secondary battery cell having an electrode consisting of a series of
connected, vertical, copper plates supporting electro deposited zinc, substantially as
described.
22. A secondary battery cell having a hydrogen electrode consisting of a
conductive support inactive in the liquid, and not penetrated by mercury, zinc
amalgam forming an active deposit thereon, and a supply of zinc consisting of one
or more sheets of amalgamated zinc, substantially as described.
23. A secondary battery cell having a hydrogen electrode consisting of a series
of conductive supports inactive in the liquid, and arranged in pairs, zinc amalgam
forming an active deposit thereon, and sheets of amalgamated zinc between said
pairs of supports forming the zinc supply, substantially as described.
24. A battery plate consisting of a series of laminae of such material as to be
increased in thickness in the action of the battery, and having soluble material
between the laminae, whereby space is provided for the increase in thickness of the
laminae, substantially as described.
25. An oxygen battery plate consisting of a series of laminae with soluble
material between the same, whereby space is provided for increase in thickness of
the laminae by oxidation, substantially as described.
26. An oxygen battery plate consisting of a series of laminae with soluble
material and conducting material between the laminae, whereby space is provided
for increase of thickness of the laminae by oxidation, and the conductivity of the
laminae increased, substantially as described.
27. An oxygen battery plate consisting of a series of laminae with soluble
material containing zinc between the same, substantially as described.
28. An oxygen battery plate consisting of a series of laminae with soluble
material and graphite between the laminae, substantially as described.
29. An oxygen battery plate consisting of a series of laminae with oxide of zinc
and graphite between the laminae, substantially as described.
30. The combination with a battery terminal or terminals consisting of a core of
high conductivity and a covering of conducting material, non-corrodable by the
battery acids, of a connector consisting of a collar of conducting material non-
corrodable by the battery acids, and constructed to receive the terminal or terminals,
and a wedge of similar material for securing the terminal or terminals in the collar,

page_text: said collar and wedge being constructed to engage the terminal or terminals by
surfaces conforming in shape thereto, whereby larger surfaces of contact are
provided, and a high conductivity secured, with material of low specific con-
ductivity, substantially as described.
31. An electric battery connector consisting of a collar of conducting material,
non-corrodable by the battery acids, and constructed to receive the conductor or
conductors, and a wedge of similar material for securing a conductor or conductors in
the collar, said collar and wedge being constructed to engage the conductor or
conductors by surfaces conforming in shape thereto, whereby large surfaces of
contact are provided, and a high conductivity is secured, with material of low
specific conductivity, substantially as described.
32. The method of making a battery plate which consists in superposing a series of
laminae with soluble material between them, and dissolving out the soluble material,
substantially as described.
33. The method of making a battery plate which consists in superposing a series
of laminae with soluble material and conductive material between them, and
dissolving out the soluble material, substantially as described.
34. The method of making a battery plate, which consists in superposing a series
of laminae with soluble material required in the battery between them, and dis-
-solving out the soluble material in the battery liquid, substantially as described.
Dated this 13th day of September 1892.
NEWTON & SON,
Agents for the Applicant.