Improvements in Galvanic Batteries.
Year: 1886

page_text: Date of Application, 27th Apr., 1886.
Complete Left, 7th Jan., 1887.
Complete Accepted, 8th Feb., 1887.
PROVISIONAL SPECIFICATION.
Improvements in Galvanic Batteries.
We, ALFRED DUN, Apothecary, and FRANZ HASSLACHER, Clerk, both of Frankfort
on the Main, German Empire, do hereby declare the nature of this invention to be as
follows
Our invention relates to a new or improved element of two cells for galvanic
batteries the essential feature of which consists in its very high electromotive force, as
the single element is capable of attaining 25 volts. In consequence of the small
resistance of the exciting and depolarising liquids employed, the strength of current
is very considerable. Notwithstanding its considerable power, however, the element.
is so constant in its action that it may be used with great advantage for electric
lighting, or for driving motors. The new element consists of a carbon negative
electrode having a depolarising liquid nitrohydrochloric acid (Aqua Regia) either
alone or mixed with ferric chloride. As solution electrode in the other cell zinc is
employed, or any other metal soluble in soda lye or at any rate on closing the circuit,
and as exciting liquid soda lye of greater or less concentration is used.
The chemical action of the element is as follows.
The zine is oxidised by the oxygen evolved and the oxide formed is dissolved by
the soda lye, while the hydrogen is at once taken up by the Aqua Regia forming
hydrochloric acid with its chlorine.
In the gradual decomposition of the Aqua Regia there is produced chlorine
together with chloro-sub-nitrous acid and chloro-nitrous acid, which can also give up
their chlorine. When the Aqua Regia is saturated with chlorine its decomposition
ceases, and only begins again, with a fresh production of chlorine, or of the two above
named compounds, when the free chlorine first evolved is taken up by hydrogen or
any other body that absorbs chlorine such as ferrous chloride. According to tho
quantity of hydrogen evolved by the action of the element, the development of
chlorine is proportional to the the absorption of the existing free chlorine, and this
lasts as long as any Aqua Regia exists.
With the presence of ferric chloride the depolarising process may be considered as
consisting in the reduction of ferric chloride to ferrous chloride by the hydrogen,

page_text: with formation of hydro-chloric acid, the ferrous chloride being, however, at once
reconverted into ferric chloride by the chlorine of the Aqua. Regia.
This takes place as long as there is any trace of the Aqua Regia present. Only
after this has disappeared does a permanent formation of ferrous chloride begin,
combined with an increase of resistance in the element. But this does not occur as
long as all the iron is present in the form of ferric chloride. It is therefore
advantageous always to have an excess of Aqua Regia present.
.
The addition of ferric chloride has therefore the important object of enabling the
element to be utilised to the fullest possible extent, without increasing the resistance,
which explains the reason why a mixture of Aqua Regia and ferric chloride renders
the element more constant than when Aqua Regia alone is used. The addition of the
ferric chloride has however also the important advantage, that by means thereof a too
rapid mingling of the inner and outer liquids is prevented. This is particularly
important when a carbon cell is used in place of an earthenware cell, in consequence
of the greater porosity of the former. On the ferric chloride mixing with the soda
lye in the walls of the porous cell, oxide of iron is formed which fills up the larger
pores without materially interfering with the necessary contact and without increasing
the resistance which is rendered very small by the good conduction of the carbon cell.
In addition the oxide of iron assists the depolarisation, and therefore also acts
beneficially in this respect.
As the hydrochloric acid is always formed afresh, it is advantageous to use Aqua
Regia containing much nitric acid, or, in replenishing, only to supplement the nitric
acid consumed.
The very high electromotive force of the element is caused by the fact that to the
electric tension between metal and carbon there is also added that existing between
the Aqua Regia with ferric chloride, and the soda lye.
If it is desired to avoid all smell during working, the hydro chloric acid of the
Aqua Regia may be replaced by chromic acid or a chromate.
In this case no pro-
duction of free chlorine ensues, and any nitrous acid fumes are at once absorbed by
the chromic acid. The depolarising action of the nitric acid will then be assisted by
that of the chromic acid. In this case platinum or aluminium may be used in place
of carbon.
ABEL & IMRAY,
28, Southampton Buildings, London, W.C.,
Agents for the Applicants.

page_text: We ALFRED DUN, Apothecary, and FRANZ HASSLACHER, Clerk, both of Frankfort
on the Main, German Empire, 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 :-
Our invention relates to a new or improved element of two cells for galvanic
batteries, the essential feature of which consists in its very high electromotive force as
the single element, is capable of attaining 25 Volts. In consequence of the small
resistance of the exciting and depolarising liquids employed, the strength of current
is very considerable. Notwithstanding its considerable power however, the element is
so constant in its action that it may be used with great advantage for electric lighting,
or for driving motors. The new element, consists of a carbon negative electrode
having as depolarising liquid nitro-hydrochloric acid (Aqua Regia) either alone or
mixed with ferric chloride. As positive electrode in the other cell zin is employed,
or any other metal soluble in soda lye or at any rate on closing the circuit, and as
exciting liquid soda lye of greater or less concentration is used.
The chemical action of the element is as follows:
The zinc is oxidised by the oxygen evolved and the oxide formed is dissolved by the
soda lye, while the hydrogen is at once taken up by the Aqua Regia forming hydro-
chloric acid with its chlorine. In the gradual decomposition of the Aqua Regia there
is produced chlorine together with chloro-sub-nitrous acid and chloro nitrous acid,
which can also give up their chlorine. When the Aqua Regia is saturated with
chlorine its decomposition ceases, and only begins again with a fresh production of
chlorine, or of the two above named compounds, when the free chlorine first evolved
is taken up by hydrogen or any other body that absorbs chlorine such as ferrous
chloride. According to the quantity of hydrogen evolved by the action of the element,
the development of chlorine is proportional to the absorption of the existing free
chlorine, and this lasts as long as any Aqua Regia exists.
With the presence of ferric chloride the depolarising process may be considered as
consisting in the reduction of ferric chloride to ferrous chloride by the hydrogen,
with formation of hydrochloric acid, the ferrous chloride being, however, at once
reconverted into ferric chloride by the chlorine of the Aqua Regia.
This takes place as long as there is any trace of the Aqua Regia present. Only
after this has disappeared does a permanent formation of ferrous chloride begin,
combined with an increase of resistance in the element. But this does not occur as
long as all the iron is present in the form of ferric chloride. It is therefore advan-
tageous always to have an excess of Aqua Regia present. The addition of ferric
chloride has therefore the important object of enabling the element to be utilised to
the fullest possible extent without increasing the resistance, which explains the reason
why a mixture of Aqua Regia and ferric chloride renders the element more constant
than when Aqua Regia alone is ured. The addition of the ferric chloride has however

page_text: also the important advantage, that by means thereof a too rapid mingling of the inner
and outer liquids is prevented. This is particularly important when a carbon cell is
used in place of an earthenware cell in consequence of the greater porosity of the
former. On the ferric chloride mixing with the soda lye in the walls of the porous
cell, oxide of iron is formed which fills up the larger pores without materially inter-
fering with the necessary contact and without increasing the resistance which is
rendered very small by the good conduction of the carbon cell.
In addition the oxide of iron assists the depolarisation and therefore also acts
beneficially in this respect.
As the hydrochloric acid is always formed afresh, it is advantageous to use Aqua
Regia containing much nitric acid, or, in replenishing only to supplement the nitric
acid consumed.
The very high electromotive force of the element is caused by the fact that to the
electric tension between metal and carbon there is also added that existing between
the Aqua Regia with ferric chloride and the soda lye.
If it is desired to avoid all smell during working, the hydrochloric acid of the
Aqua Regia may be replaced by chromic acid or a chromate. In this case no pro-
duction of free chlorine ensues, and any nitrous acid fumes are at once absorbed by
the chromic acid. The depolarising action of the nitric acid will then be assisted by
that of the chromic acid. In this case platinum or aluminium may be used in place
of carbon.
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed, we declare that what we claim is :
-The use in a two-cell galvanic element of carbon as negative electrode in com-
bination with nitro-hydrochloric acid (Aqua Regia) in the one cell and as positive
electrode, zinc or other metal soluble in soda lye, or soluble therein on closing the
circuit, in the other cell.
2-The use of ferric chloride in addition to the aqua regia in a two-cell element.
such as is referred to in the first claim, for the purpose of increasing the constant
nature of the element and decreasing the diffusion.
3 In a two-cell element such as is referred to in the first claim, the use of chromic
acid or of a chromate in place of the hydrochloric acid, for preventing smell, with or
without the substitution of platinum or aluminium for the carbon.
ABEL & IMRAY,
Agents for the Applicants.