mprovements in Secondary Batteries.
Year: 1885

page_text: f
mprovements in Secondary Batteries.
I, HERBERT JOHN ALLISON, of the firm of Allison Brothers, of 52 Chancery
Lane, London, in the County of Middlesex, Patent Agents, do hereby declare the
nature of said invention for " IMPROVEMENTS IN SECONDARY BATTERIES," (a com-
munication to me from abroad by Park Benjamin, Ph.D., of the City and State of
New York, United States of America, Consulting Engineer) to, be as follows:
*
The invention consists in a new secondary or storage cell in which I use a
liquid consisting of a solution of zine sulphate to which magnesium oxide is added,
and electrodes which may be compounded or prepared according to the methods.
hereinafter set forth.
.
Referring, first, to the liquid which I employ, this as above stated is prepared by
adding to a zinc sulphate solution, magnesium oxide in such quantity as will be
sufficient to neutralize the sulphuric acid set free when the zinc sulphate solution.
is decomposed on the charging of the cell. The metallic zinc also freed from the
sulphate solution is deposited on the cathode. The object of neutralizing the
sulphuric acid as it is liberated, is to prevent local action of said acid on
the metallic zinc and also on the peroxidized plate. In this way I avoid 'the'
loss of energy due to such local action and greatly increase the durability of
the cell.
:
The material
The anode of my cell is preferably made in the following manner.
of which it is to be composed, such for example as lead or an alloy of lead with a'
non-oxidizable metal such as antimony or bismuth, is melted, and then cooled
until it. becomes plastic. While thus plastic I stir it until it assumes a finely.
divided condition and shows a tendency to solidify.. The mass is finally allowed
to cool in a mould when the small particles of which it is composed cohere at their
points of contact, thus rendering the electrode very porous, causing it to expose a
large active surface and thus greatly saving time in the "formation "of the plate.
The object of adding antimony when an alloy as above described is used is to lower
the fusing point of the mass.
;

page_text: I also make my anode by melting lead or by preparing an alloy of lead and a
non-oxidizable metal as before stated of lead and antimony for example, and then
while the same is in a molten state adding sufficient mercury to form a pasty
amalgam. The amalgam made from the alloy should be pasty while hot. To this
compound I add any substance capable of storing electrical potential in the storage
battery, such as lead oxide, and finally I mix in any substance which is inert in
the cell, but capable of occluding gases, such as pulverized carbon, and then mould
as before. The advantage of adding the carbon is that it acts as a means of
absorbing the hydrogen from the negative plate and the oxygen which escapes
from the positive plate and thus tends to prevent polarization. It also renders
the electrode more porous and acts as a conductor of electricity to diminish the
internal resistance of the electrode. The quantities of lead oxide and carbon
added should be about equal, and the resulting body should be hard, firm and
coherent when cold.
The electrode made in accordance with the above described methods may be
prepared in the melting vessel and allowed to cool therein during stirring, but
there is some difficulty attending this, as the mass may become overheated, or if
mercury is added the same may be vaporized, or the mass may not melt equally,
some parts being of greater consistence than others, or it may not solidify equally
when the vessel is removed from the fire. These disadvantages may be overcome
by care in manipulation, but it is much more convenient and simple to make the
electrode in the following way :-
-
I first melt the material in a ladle or crucible over a fire. As soon as it is
melted I turn it into a vessel of any desired form or construction, which is provided
with a jacket or surrounded with a coiled pipe through which steam or superheated
steam is caused to circulate. The arrangement of this apparatus is not material so
long as it be such that the inner vessel may receive heat from the steam circulating
around it.
By means of the steam the supply of which may be regulated by a suitable hand
valve or by any apparatus operating automatically to cut off the steam, when a
certain temperature is obtained, I heat the inner vessel as nearly as possible to the
temperature of the material to be treated, when it shall have cooled down to a
pasty or viscid state. This can easily be found by simply measuring the tempera-
ture of a sample of the material melted and then cooled as stated. When the
molten material is introduced into the vessel it is stirred and as it is stirred it
cools; but by reason of the temperature of the vessel it is not permitted to solidify
or to cool down below or much below the pasty state.
It follows then that the stirring process can be efficiently and rapidly done, and
that as the material is maintained throughout at a uniform, temperature and in a
uniform state, all parts of it will be equally affected, and if other ingredients be
added they can be completely incorporated with it.
After the stirring process is finished I press the material or the compound while
hot, into moulds.. I do not cast it in the sense of running it into a mould and
allowing it to assume permanent form by natural solidification. It is essential
that the material should be put into the moulds in a hot, or pasty state-and while
so hot and pasty, that it should be pressed into form. I find that when the
electrode is made in the manner above described its structure is very homogeneous
and any tendency it may have to crumble or break in the battery by use, is
reduced to a minimum.
The cathode of my improved cell as already stated receives from the liquid
above described a metallic deposit of zinc. I find that when the surface of the
cathode, of lead for example, is unprotected, it becomes somewhat oxidized and
roughened. I have also found that when several secondary cells are connected in
series and during their discharge the weakest cell of course becomes exhausted
first. It. then amounts simply to an electrolytic cell, which the others charge,
thereby reversing its polarity. As a consequence the electrode which was before

page_text: the cathode now becomes the anode and is oxidized and roughened by reason
thereof and rendered unfit to receive the metallic deposit.
I have discovered that considerable advantage. is gained by giving the cathode
a surface of non-oxidizable metal. This may be done by covering, coating or
plating the cathode by any well known process, such as by dipping.
By reason of the surface of the cathode being thus rendered non-oxidizable, it
remains unattacked and in its original smooth and clean condition and hence fit
at all times to receive the metallic deposit. It is not necessary to remove the
cathode thus protected for the purpose of cleaning it. So also in event of reversal
of polarity of the cell as in the case of cells connected in series as above set forth,
the original cathode cannot become oxidized by the gas or acid set free and hence
remains unimpaired in efficiency.
I find also that to such non-oxidizable surface the metallic deposit adheres more
perfectly. The deposit formed upon the non-oxidizable surface is a reguline
deposit, that is, substantially solid, compact and having no tendency to crack,
break or scale off. I have practically used a cathode of lead_covered or washed
with gold in a thin film.

page_text: COMPLETE SPECIFICATION..
Improvements in Secondary Batteries.
I, HERBERT JOHN ALLISON, of the firm of Allison Brothers, of 52 Chancery
Lane, London, in the County of Middlesex, Patent Agents, do hereby declare the
nature of this invention, which has been communicated to me from abroad by
Park Benjamin, Ph.D., of the City and State of New York, United States of
· America, Consulting Engineer, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement :—
The invention consists in a new secondary or storage cell in which I use a liquid
consisting of a solution of zinc sulphate to which magnesium oxide is added, and
electrodes which may be compounded or prepared according to the methods herein-
after set forth.
Referring first, to the liquid which I employ, this as above stated is prepared by
adding to a zinc sulphate solution, magnesium oxide in such quantity as will be
sufficient to neutralize the sulphuric acid set free when the zinc sulphate solution
is decomposed on the charging of the cell. The metallic zinc also freed from the
sulphate solution is deposited on the cathode. The object of neutralizing the
sulphuric acid as it is liberated, is to prevent local action of said acid on
the metallic zine and also on the peroxidized plate. In this way I avoid the
loss of energy due to such local action and greatly increase the durability of
the cell.
The anode of my cell is preferably made in the following manner. The material
of which it is to be composed, such for example as lead or an alloy of lead with a
non-oxidizable metal such as antimony or bismuth, is melted, and then cooled until
it becomes plastic. While thus plastic I stir it until it assumes a finely divided
condition and shows a tendency to solidify. The mass is finally allowed to cool in
a mould when the small particles of which it is composed cohere at their points of
contact, thus rendering the electrode very porous, causing it to expose a large
active surface and thus greatly saving time in the "formation" of the plate. The
object of adding antimony when an alloy as above described is used is to lower the
fusing point of the mass.
I also make my anode by melting lead or by preparing an alloy of lead and a
non-oxidizable metal as before stated of lead and antimony for example, and then
while the same is in a molten state adding sufficient mercury to form a pasty
amalgam. The amalgam made from the alloy should be pasty while hot. To this
compound I add any substance capable of storing electrical potential in the storage
battery, such as lead oxide, and finally I'mix in any substance which is inert in
the cell, but capable of occluding gases, such as pulverized carbon, and then mould
as before. The advantage of adding the carbon is that it acts as a means of
absorbing the hydrogen from the negative plate and the oxygen which escapes
from the positive plate and thus tends to prevent polarization. It also renders the

page_text: electrode more porous and acts as a conductor of electricity to diminish. the
internal resistance of the electrode. The quantities of lead oxide and carbon added.
should be about equal, and the resulting body should be hard, firm and coherent
when cold.
"
The electrode made in accordance with the above described methods may be
prepared in the melting vessel and allowed to cool therein during stirring, but
there is some difficulty attending..this, as the mass. may become overheated, or if
mercury is added the same may be vaporized, or the mass. may not melt equally,
some parts being of greater consistence than others, or it may not solidify equally
when the vessel is removed from the fire. These disadvantages may be overcome
by care in manipulation, but it is much more convenient and simple to make the
electrode in the following way:-
I first melt the material in a. ladle or crucible over the fire. As soon as it is
melted I turn it into a vessel of any desired form or construction, which is provided
with a jacket or surrounded with a coiled pipe through which steam or superheated
steam is caused to circulate. The arrangement of this apparatus is not material so
long as it be such that the inner vessel may receive heat from the steam circulating
around it.
By means of the steam the supply of which may be regulated by a suitable hand
valve or by any apparatus operating automatically to cut off the steam, when a
certain temperature is obtained, I heat the inner vessel as nearly as possible to the
temperature of the material to be treated, when it shall have cooled down to
a pasty or viscid state. This can easily be found by simply measuring the
temperature of a sample of the material melted and then cooled as stated. When
the molten material is introduced into the vessel it is stirred and as it is stirred it
cools; but by reason of the temperature of the vessel it is not permitted to solidify
or to cool down below or much below the pasty state.
L
It follows then that the stirring process can be efficiently and rapidly done, and
that as the material is maintained throughout at a uniform temperature and in a
uniform state, all parts of it will be equally affected, and if other ingredients be
added they can be completely incorporated with it.
After the stirring process is finished I press the material or the compound while
hot, into moulds. I do not cast it in the sense of running it into a mould and
allowing it to assume permanent form by natural solidification. It is essential that
the material should be put into the moulds in a hot or pasty state-and while so
hot and pasty, that it should be pressed into form. I find that when the electrodé
is made in the manner above described its structure is very homogeneous and any
tendency it may have to crumble or break in the battery by use, is reduced to a
minimum.
:
The cathode of my improved cell as already stated receives from the liquid above
described a metallic deposit of zinc. I find that when, the surface of the cathode,
of lead for example, is unprotected, it becomes somewhat oxidized and roughened.
I have also found that when several secondary cells are connected in series and
during their dischargo the weakest cell of course becomes exhausted first. It then
amounts simply to an electrolytic cell which the others charge, thereby reversing
its polarity. As a consequence the electrode which was before the cathode now
becomes the anode and is oxidized and roughened by reason thereof and rendered
unfit to receive the metallic deposit.
'
I have discovered that considerable advantage is gained by giving the cathode a
surface of non-oxidizable metal. This may be done by covering, coating or plating
the cathode by any well known process, such as by dipping.
By reason of the surface of the cathode being thus rendered non-oxidizable, it
remains unattacked and in its original smooth and clean condition and hence fit at
all times to receive the metallic deposit. It is not necessary to remove the cathode
thus protected for the purpose of cleaning it.. So also in event of reversal of

page_text: polarity of the cell as in the case of cells connected in series as above set forth, the
original cathode cannot become oxidized by the gas or acid get free and hence
remains unimpaired in efficiency.
I find also that to such non-oxidizable surface the metallic deposit adheres more
perfectly. The deposit formed upon the non-oxidizable surface is a reguline
deposit, that is, substantially solid, compact and having no tendency to crack;
break or scale off. I have practically used a cathode of lead covered or washed
with gold in a thin film.
'
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. In a secondary cell, a neutral electrolytic liquid containing zinc sulphate and
magnesium oxide, substantially as described.
2. In a secondary or storage cell electrodes of lead and a neutral electrolytic
liquid containing zinc sulphate and magnesium oxide, substantially as described.
3. An electrode for secondary cells made by melting a suitable material or
materials, stirring said material during cooling until it comes to a plastic and
finely divided condition and pressing the mass into shape, substantially as
described.
4. An electrode for secondary cells made by melting an alloy of lead and a non-
oxidizable metal, stirring said alloy during cooling until it comes to a plastic
and finely divided condition and pressing the mass into shape, substantially as
described.
5. An electrode for secondary cells composed of an amalgam of lead and
mercury, any substance active in the cell, and any substance capable of occluding
gases, substantially as described.
6. An electrode for secondary cells composed of an amalgam of an alloy of lead
and any other non-oxidizable metal or metals said alloy having a lower fusing
point than lead alone, any substance active in the cell and any substance capable
of occluding gases, substantially as described.
7. The process of making electrodes for secondary batteries consisting in first
preparing an amalgam of lead and mercury, second then adding any active
substance; third, adding any substance inert in said battery and capable of
occluding gases and fourth, forming the electrode into shape, substantially as
described.
8. The process of making electrodes for secondary batteries consisting in first,
making an alloy of lead and any other non-oxidizable metal or metals, said alloy
having a lower fusing point than lead; second, then adding mercury to form an
amalgam which shall be pasty while hot; third, then adding any substance active
in a secondary battery, fourth, then adding any substance inert in said battery and
capable of occluding gases; and fifth, moulding the electrode into suitable shape,
substantially as described.
9. The process of making electrodes for secondary batteries consisting in first
melting the material of which the electrode is to be composed; second, cooling
said material in a vessel heated by steam at or near the temperature of said
material while in a pasty or viscid state, and stirring said material in said vessel
while cooling until it reaches said viscid state; third, pressing said material while
in said viscid state in form in a suitable mould or moulds, substantially as
described.
10. The process of making electrodes for secondary batteries consisting in
melting a material which the electrode is to contain, cooling said material in a
vessel heated by steam at or near the temperature of said material while in a
pasty or viscid state, stirring said material in said vessel while cooling until it
reaches said viscid state and at the same. time adding any other ingredient or
ingredients which it is desired. to combine with said material, and pressing said

page_text: compound while in said viscid state in form in a suitable mould or moulds, sub-
stantially as described.
11. In a secondary cell, a cathode having a non-oxidizable metallic surface, sub-
stantially as described.
12. In a metallic deposition secondary cell a cathode having its surface covered
with a non-oxidizable metal, substantially as described.
13. In a metallic deposition secondary cell, a cathode having its surface coated
with gold, substantially as described.
14. In a metallic deposition secondary cell, a cathode of lead having its surface
coated with gold, substantially as described.
15. A secondary cell containing a neutral électrolytic liquid, a cathode having a
non-oxidizable metallic coating and a lead anode, substantially as described.
Dated this 29th day of October 1885.
ALLISON BROS,
Agents for the Applicant.