ROVEMENT
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said John Hubert Davies at
the Office of the Commissioners.of Patents on the 1st July 1882.
JOHN HUBERT DAVIES of Ipswich in the County of Suffolk
IN GALVANIC BATTERIES
"
"IMPROVEMENTS
This invention has for its object improvements in galvanic batteries.
The process of obtaining electrical currents by means of galvanic batteries in
which zinc is consumed is very well understood, but the cost of the zinc has limited
the employment of this method. It has been found cheaper to obtain electric
currents in a more roundabout way from the combustion of coal in the furnace of
a steam engine which is thus enabled to generate currents by driving a dynamo
machine. But although currents are thus produced much more cheaply than by
the combustion of zinc in batteries the value of the electrical energy obtained is
very much less than the total amount of the energy of the coal that is consumed
and by far the larger part of this loss is incurred in the operation of turning the
energy of the combustion of the coal into moving power in the engine.
The object of this invention is to produce electric currents more directly from
the combustion, or combination with oxygen of carbon or carbon compounds.
The method which I employ is illustrated by Figure 1 of the annexed drawings
which represents one of the simplest forms that can be given to my battery. A is
a vessel containing nitrate of potassium which is melted by heat. In this is
immersed a plate of carbon C having a wire attached to it, also a kind of cage B
made of fine iron wire gauze or netting of several thicknesses and into which is
carried the tube D. The tube D may be of the same material as the cage B or of
glass, porcelain or earthenware. The tube D and also the tube F pass through
the stopper of another vessel E in which nitric acid is contained or generated,
while to the outside end of F is connected a tube from any convenient reservoir
of air.

page_text: When air is forced through F it carries with it into D and B fumes of nitric
acid and this mixture finds its way through the meshes of the cage B into the
melted nitrate of potassium.-It will then be found that on connecting the wires
from the carbon which is the positive element and the iron cage which in con-
junction with the mixed gases is the negative element, that a strong current of
electricity is produced. It is not altogether necessary that nitric acid fumes should
be employed for a good result may be obtained by simply passing air alone
' into D.
Many different forms may be given to this battery. I have obtained good
results by using for the positive element represented by O in Figure 1 ordinary gas
coke, hard gas retort carbon, the carbons that are used for electric arc lamps a
mixture of coke and coal, wood charcoal and the like..
Or compound substances containing a large proportion of carbon may be
employed.
In regard to the negative element, this may be a plate against which the gas or
mixture of gases is blown or it may be a perforated tube or chamber of sheet
metal or metal in a porous condition, or a netting or metal gauze. Or the negative
element may be formed of a number of small lumps or grains of metal or it
may be melted metal through which air or a mixture of gases is allowed to.
bubble.
As far as my experiments show at present iron appears to be one of the best
metals for the negative element or conductor, though very good effects have been
obtained with platinum and tin and effects little inferior with silver and copper.
A roughened surface adds to the efficiency of the conductor and I attain this either
by mechanical means such as scraping or by dipping in acid, or by covering with
& deposit of platinum in a finely divided state. Or it may be covered with an
oxide.
I sometimes cause the conductor to be moved in the liquid. The negative con-
ductor may be arranged so that part of its surface is in the liquid and part above
the surface and in the vapour or gas and the part that is in the liquid and tho
part that is in the vapour or gas may be made to change places, so that, say one
half of the conductor is alternately in the gas and in the liquid.
For the conducting liquid between the positive and negative elements I have
used several compounds-One of the best for the purpose being nitrate of potassium
(sometimes called nitre or saltpetre) melted as before stated by heat. The heat
may be applied by a fire or furnace. Or as the electric current generates heat in
the circuit through which it passes, the resistance of the battery cell may be so
proportioned that when once the nitrate of potassium (or other substance) is
melted or in a state to conduct the current the heat produced by the current
itself will maintain a proper temperature.
Instead of Nitrate of potassium I have used Dioxide of Barium, Monoxide of
Barium, Nitrate of Barium, Dioxide and other oxides of Lead, Nitrate of lead,
Cupric Nitrate, Borax and other compounds containing oxygen, these being either
melted by heat or moistened by a liquid.
Two or more liquid conductors may be used separated by a porous diaphragm
of earthenware, asbestos pumicestone or some other similar material, the positive
element being placed in, or in contact with one liquid and the negative element in
or in contact with another.
The gas which is caused to come in contact with the negative plate may be a
simple gas such as oxygen or ozone or a mixture of gases such as atmospheric air
and this latter I prefer to use in most cases on account of its cheapness.-The gas
or gaseous mixture may be used under a very small pressure, or kept at a con-
siderable pressure on or in the negative plate or conductor, and to enable this to
be done the height of the. liquid conductor above the negative conductor may be
increased or by another method which is probably the best, the whole cell may
be enclosed as shewn in Figure 2. In this figure H is an outer vessel into which

page_text: air or gaseous mixture is forced at H¹ beneath a partition of perforated iron I to
which the negative conductor K is attached. L is an inner vessel closed at the
sides but with a perforated bottom on which asbestos is laid. Over the asbestos
the vessel L is filled with carbon in pieces and L' is a carbon.slab laid upon the
top. M is the positive conductor it is attached to the slab L'. N is the exit pipe
from the vessel H it contains a valve which may be loaded to maintain any desired
pressure in the apparatus. O is a similar exit pipe from the inner chamber L, it
also is provided with a valve. The vessel H contains liquid potassium nitrate in
which the carbon is partly immersed. The gaseous products of the combination
or reaction of the carbon pass off by the pipe O.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Hubert Davies in the Great Seal Patent Office on the
1st January 1883.
JOHN HUBERT DAVIES of Ipswich in the County of Suffolk
IN GALVANIC BATTERIES
"
"IMPROVEMENTS
This Invention has for its object improvements in galvanic batteries. The
process of obtaining electrical currents by means of galvanic batteries in which zinc
is consumed is very well understood but the cost of the zinc has limited the
employment of this method. It has been found cheaper to obtain electric currents
in a more roundabout way from the combustion of coal in the furnace of a steam
engine which is thus enabled to generate currents by driving a dynamo machine.
But although currents are thus produced much more cheaply than by the com-
bustion of zinc in batteries the value of the electrical energy obtained is very
much less than the total amount of the energy of the coal that is consumed and
by far the larger part of this loss is incurred in the operation of converting the
energy of the combustion of the coal into moving power in the engine.
The object of this Invention is to produce electric currents more directly from
the combustion or combination with oxygen of carbon or carbon compounds and
especially to effect this combustion at the expense of the oxygen of the air.
The method which I employ is illustrated by Figure 1 of the annexed Drawings
which represents one of the simplest forms that can be given to my battery. A is
a vessel containing nitrate of potassium which is melted by heat. In this is
immersed a plate of carbon C having a wire attached to it as also has the kind of
cage B made of fine iron wire gauze or netting of several thicknesses, and into
which is carried the tube D. The tube D may be of the same material as the
cage B or of glass, porcelain, or earthenware. The tube D and also the tube F
pass through the stopper of another vessel E in which nitric acid is contained or
generated, the vessel being maintained at a suitable temperature, while to the
outside end of F is connected a tube from any convenient reservoir of air. When
air is forced through F it carries with it into D and B fumes of nitric acid and
this mixture finds its way through the meshes of the cage B into the melted
nitrate of potassium. It will then be found that on connecting the wires from
the carbon which is the positive element and the iron cage which in conjunction
with the mixed gases is the negative element, that a strong current of electricity
is produced. Although I much prefer to use nitric acid vapour or fumes it is
not altogether necessary that they should be employed for a good result may be
obtained by simply passing air alone into D. The chemical action going on in the
battery appears to be principally as follows:-
The carbon is oxidised by the nitrate of potassium and oxygen is supplied to
the latter at the negative conductor by the nitric acid fumes, the air passed
through reoxidises the decomposed nitric acid either wholly or partially, and this
when conducted away from the battery into a suitable receiver and reconverted
into strong nitric acid may be used again. In the case of air being alone employed
to "depolarize" the negative conductor, its action may be to stir up the liquid so as
to continually bring fresh portions into contact with the conductor and also to
supply oxygen in some degree to the nitrate of potassium. As is mentioned
bereafter other gases may be used instead of ordinary air for this depolarization of
the negative conductor, being mixed or not with nitric acid vapour.
Many forms may be given to this battery and various substances used in it. It
is not necessary to employ pure carbon for I have obtained good results by using

page_text: as the positive element represented by C in Figure 1 ordinary gas coke, hard gas
retort carbon, compressed carbon such as those carbons that are used for electric
arc lamps, a mixture of coke and coal, wood charcoal and the like or other
compound substances containing a large proportion of carbon may be employed.
This positive element may be in pieces or formed or cut into a single mass.
In regard to the negative conductor this may be a plate of any convenient form
against which the gas or mixture of gases is blown or caused to come in contact,
or it may be a perforated tube or chamber of sheet metal or metal in a porous
condition or a metal netting or gauze. Or it may consist of a number of small
lumps or grains of metal supported by a metal gauze or in any other suitable
manner or it may be melted metal either of these having a conducting wire in
connection with it and through or against either of which the air or other gas or
mixture of gases is caused to pass or come in contact. This may be effected in
various ways, but the method I have generally employed is to force or blow the
gases through or against the negative conductor either by some kind of pump or
by bellows or by the weight of a gas holder in which the gas may be contained.
Commonly I force air into a vessel containing nitric acid at a boiling temperature
and I afterwards lead the air charged with acid vapour to the negative conductor.
Sometimes I use the vapour of nitric acid without admixture with air and then
I heat the nitric acid to such a degree as to generate vapour of a tension sufficient
to force its way into the battery cell. The reduced vapour passing away from the
battery cell I reconvert into nitric acid at the expence of atmospheric oxygen as
already stated:
Another plan is to create a partial vacuum above the conducting liquid or liquids
and admit the gas or gaseous mixture into the negative conductor, but I do not
consider this is quite so good an arrangement as that first mentioned. Very many
different forms, shapes and arrangements may be given to the negative conductor
and I do not by any means confine myself to those described in this Specification
which are mentioned as best illustrating the principle and general mode of working
the battery.
The kind of metal used for the negative conductor of course depends upon the
nature of the liquid conductor employed in the battery. In the case of melted
nitrate of potassium, especially iron appears to be one of the best metals for the
negative conductor though very good effects have been obtained with platinum
and tin and effects little inferior with silver and copper. When the other liquid
conductors mentioned hereafter are used instead of nitrate of potassium, platinum
appears to be the most suitable metal for the negative conductor. A roughened
surface adds to the efficiency of the conductor and I. increase the natural roughness
of the surface either by mechanical means such as scraping, or by dipping in acid
or by covering with a deposit of platinum in a finely divided or spongy state. Or
it may be covered with an oxide.
:
I sometimes cause the negative conductor to be moved in the liquid; it may be
arranged so that part of its surface is in the liquid and part above the liquid and
in the vapour or gas, or mixture of them and the part that is in the liquid and the
part that is in the vapour or gas or mixture of them may be made to change places
either continuously or at short intervals of time so that say one half of the
conductor is alternately in the gas and in the liquid. One of the most convenient
forms for this arrangement is a circular metal disc revolving upon a suitable
conducting axis just above the surface of the liquid so that its lower portion is in
the liquid and its upper part in the gas; connection to the outside wire being most
conveniently made through the axis.
•
For the conducting liquid between the positive and negative elements I use
several compounds. One of the best for the purpose being nitrate of potassium
(sometimes called nitre or saltpetre) melted as before stated by heat. The heat
may be applied by a fire or furnace of any kind. Or as the electric current
generates heat in the circuit through which it passes the internal resistance of the
battery cell may be so proportioned to the other resistance in the circuit that
•

page_text: when once the nitrate of potassium (or other substance) is melted or in a state to
conduct the current and to supply oxygen to the carbon the heat produced by the
current itself will maintain a proper temperature.
.
Instead of nitrate of potassium I have used many other electrolytic conductors
with various results as regards efficiency. Dioxide of lead moistened or mixed
with nitric acid gives very good results and avoids the necessity of raising the
battery to a high temperature. Nitrate of lead also mixed with nitric acid gives.
a fairly good electro motive force. Ordinary red lead placed in a vessel with
nitric acid gives the dioxide of lead as a powder and the nitrate which is kept in
solution and this mixture may be used for the conductor between the positive and
negative elements I have also used dioxide of barium monoxide of barium,
nitrate of barium, cupric nitrate, borax and other compounds containing oxygen
these being either melted by heat or mixed with a suitable liquid.
Two or more liquid conductors may be used separated by a porous diaphragm of
earthenware, asbestos, pumicestone or some other similar material, the positive 1
element of the battery being placed in or in contact with one liquid and the
negative element in or in contact with another. For instance I have used a
solution of nitrate of lead in water as the liquid in which the carbon is placed and
nitric acid as the liquid in contact with the negative element.
One of the most important parts of the Invention consists in the use of the
oxygen containing gas or vapour or mixture of them which is caused to pass
through or in any way come in contact with the negative conductor. Although
I prefer in most cases to use atmospheric air on account of its cheapness I
sometimes employ a gas having a larger proportion of oxygen such as atmospheric
air with some of its nitrogen removed by any convenient method or having a
further quantity of oxygen added to it, or oxygen itself or ozone or a mixture of
either of these with or without the addition of nitric acid vapour or fumes as
before mentioned.
The gas or gaseous mixture which it is sometimes advantageous to heat may be
kept at about ordinary atmospheric pressure at the negative conductor or the
pressure may be considerably increased, this I find preferable to a certain extent
and to enable it to be done the height of the liquid above the negative conductor
may be increased or by another method which is probably better, the whole cell
may be enclosed as shewn in Figure 2. In this Figure H is an outer vessel into
which air or gaseous mixture is forced at H¹ beneath a partition of iron I made
porous in some way to allow the passage of the gas and to this is attached the
conducting wire K. Lis an inner vessel closed at the sides but having a perforated
bottom on which asbestos is laid. Over the asbestos the vessel L is filled with
carbon in pieces and L' is a carbon slab laid upon the top for the purpose of
making a good connection between the carbon pieces and the wire M which is
attached to the slab. N is the exit pipe from the vessel H it contains and is
closed by a valve which may be loaded to maintain any desired pressure in
the apparatus. O is a similar pipe from the inner chamber L it also is provided
with a valve. The vessel H contains melted nitrate of potassium in which the
carbon is partially immersed.
The proportion of the gas entering by H' which is not absorbed by the nitrate
of potassium is carried away through the pipe N. And the gaseous products of the
combination or reaction of the carbon pass off by the pipe O,
Having thus described the nature of my said Invention and the manner of
performing the same I would have it understood that I claim :-
First. The construction and use of batteries in which carbon is employed as the
positive element and is consumed by or enters into combination with oxygen, which
as a gas or gaseous mixture or compound is supplied at the negative element of the
⚫ battery substantially as described.
Second. The construction and use of batteries in which a mixture of coke and
coal is employed as the positive element and is consumed by or enters into

page_text: combination with the oxygen of a liquid substance forming the electrolytic
conductor of the battery substantially as described.
Third The use as the negative element in carbon batteries of conductors of
perforated metal or metal in a porous condition or a metal netting or gauze, or a
number of small pieces or grains of metal, these conductors having gas or vapour
passed in contact with them substantially as described.
Fourth. The use as the negative element of carbon batteries of metal
conductors having their surfaces roughened either by mechanical means or by
dipping in acids or by having platinum in a finely divided or spongy state
deposited upon them and having gas or vapour passed in contact with them
substantially as described.
Fifth. The use in a carbon battery of a negative conductor of metal so
arranged that part of its surface is in the conducting liquid and part above and
in the vapour or gas or mixture of them the part above, and the part below being
made to change places either continuously or at short intervals of time
substantially as described.
Sixth. The use in a carbon battery and together with gas or vapour of a
negative conductor made of iron, of platinum of tin, of silver or of copper
substantially as described
Seventh. The construction and use of carbon batteries in which atmospheric air,
oxygen or ozone is caused to pass in contact with the negative conductor
substantially as described.
Eighth. The use in a carbon battery of nitric acid vapour to supply oxygen at
the negative conductor substantially as described.
Ninth. The construction and use of batteries in which carbon is employed as the
positive element and nitrate of potassium melted by heat as the electrolytic
conductor and in which oxygen is supplied at the negative plate to such electrolytic
conductor substantially as described.
Tenth. The use of dioxide or nitrate of lead mixed with a suitable liquid such
as nitric acid for the conducting medium between the positive and negative
elements of carbon batteries substantially as described.
Eleventh. The arrangement of a carbon battery by the adjustment of the
internal and external resistances in such manner that the heat produced by the
current maintains the necessary temperature within the battery substantially as
described.
In witness whereof I the said John Hubert Davies have hereunto set my
hand and seal this twenty seventh day of December in the year of our
Lord One thousand eight hundred and eighty two