Plates, or Partitions for Electric Batteries.
Year: 1887

page_text: Date of Application, 20th July, 1887
Complete Left, 19th May, 1888
Complete Accepted, 22nd June, 1888
Plates, or Partitions for Electric Batteries.
We, ERHARD LUDWIG MAYER, and HENRY LIEPMANN, both of Nelson Wharf,
Millwall, London, E., Electrical Engineers, do hereby declare the nature of this
invention to be as follows:-
Our invention relates to improvements in porous pots, plates or partitions for
electric batteries whereby certain advantages are obtained.
A drawback which exists in porous pots, plates or partitions as at present constructed
lies in the fact that it is extremely difficult or even impossible to make them of such
uniform structure and composition that they will always offer a constant resistance to
the passage through them either of the electrolyte or electrolytes with which they are
employed or of a constituent or constituents thereof. As at present manufactured
the resistances of the porous pots, plates or partitions vary enormously among
themselves; and those suited for any particular purpose can only be separated and
chosen by a system of careful selection.
The object of our invention is to overcome this drawback, and to enable porous
pots, plates and partitions to be constructed of any desired and predetermined resist-
ance, so as to be exactly suited for the purposes for which they are to be employed,
that is, suited to the nature of the battery materials with which they are to be in
contact.
-
In carrying our invention into effect, we employ pots, plates or partitions con-
structed of biscuitware, or of porous earthenware, after the usual manner, but
preferably of as open a texture as is convenient; and in order to bring them up to
the requisite resistance we precipitate or deposit in their pores, and on their surface,
bodies of such nature that when the porous pots, plates or partitions are in use, the
said bodies will not themselves enter into any chemical reaction with the electrodes or
electrolytes, or otherwise undergo chemical or physical change which will be deleterious
to the action of the battery.

page_text: This precipitation or deposition we may bring about by chemical, electrolytic or
thermal decomposition.
When we bring about such precipitation or deposition by means of chemical
decomposition we impregnate the porous pots, plates or partitions with a suitable
compound or chemical reagent and this we cause to be acted upon by another suit-
able compound or chemical reagent, so that a body such as we have hereinbefore
indicated, namely one which will not enter into any chemical reaction with the
electrodes or electrolytes with which it may come in contact, or otherwise undergo
chemical or physical alteration which would be deleterious to the action. of the
battery, is separated and precipitated or deposited in the pores or interstices and on
the surface of the said porous pots plates or partitions. We desire it to be under-
stood that the body which is to be precipitated or deposited may exist either in the
compound or reagent with which the porous pots plates or partitions are first
impregnated, or in the compound or reagent which is afterwards applied.
When we bring about such precipitation or deposition by electrolytic decomposition
we impregnate the porous pots plates or partitions with a compound or reagent
containing the body or clement which it is desired to deposit or precipitate and
thereafter we subject the porous pots plates or partitions thus impregnated to the
action of an electric current, so that the impregnating compound may be decomposed
and its desired constituent or constituents be precipitated or deposited in the pores
and interstices and upon the surface of the porous pots plates or partitions.
When we bring about such precipitation and deposition by thermal decomposition
we impregnate the porous pots plates or partitions with a substance or compound con-
taining the body or element which-it is desired to precipitate or deposit ; and thereafter
we subject the impregnated porous pots plates or partitions to the action of heat, so
as to bring about the necessary decomposition for the purpose of depositing in the
pores and interstices of the porous pots plates or partitions the body required to be
precipitated or deposited.
It will be seen that by means of our invention any desired predeterinined resistance
of the porous pots plates or partitions may be obtained by simply taking into account
the conditions of the case, and proportioning the strengths of the chemical reagents,
the strength of the electric current, or the temperature, as the case may be, employed
in the carrying out of the operation.
Dated this 20th day of July 1997

page_text: Plates, or Partitions for Electric Batteries.
We, ERHARD LUDWIG MAYER, and HENRY LIEPMANN, both of Nelson Wharf,
Millwall, London, E., Electrical Engineers, 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 improvements in porous pots plates or partitions for electric
batteries whereby certain advantages are obtained.
A drawback which exists in porous pots plates or partitions as at present constructed
lies in the fact that it is extremely difficult or even impossible to inake them of such
uniform structure and composition that they will always offer a constant resistance
to the passage through them either of the electrolyte or electrolytes with which they
are employed or of a constituent or constituents thereof. As at present manufactured
the porous pots plates or partitions vary enormously in resistance among themselves
and those suited for any particular purpose can only be separated and chosen by a
system of careful selection.
The object of our invention is to overcome this drawback and to enable porous pots
plates or partitions to be constructed of any desired and predetermined resistance so
as to be exactly suited for the purpose for which they are to be employed that is
suited to the nature of the battery materials with which they are to be in contact.
In carrying our invention into effect we employ pots plates or partitions constructed
of biscuit ware or of porous earthenware after the usual manner but preferably of as
open a texture as is convenient and in order to bring them up to the requisite
resistance we precipitate or deposit in their pores and on their surface bodies of such
nature that when the porous pots plates or partitions are in use the said bodies will
not themselves enter into any chemical action with the electrodes or electrolytes (or
otherwise undergo chemical or physical change) which will be deleterious to the
action of the battery.
This precipitation or deposition we may bring about by chemical or thermal
decomposition.
When we bring about such precipitation or deposition by means of chemical
decomposition we impregnate the porous pots plates or partitions with a suitable
compound or chemical reagent and this we cause to be acted upon by another suitable
compound or chemical reagent so that a body such as we have hereinbefore mentioned
namely one which will not enter into any chemical reaction with the electrodes or
electrolytes with which it may come in contact (or otherwise undergo chemical or
physical alteration) which would be deleterious to the action of the battery is

page_text: separated and precipitated or deposited in the pores or interstices and on the surface
of the said porous pots plates or partitions. We desire it to be understood that the
body which is to be precipitated or deposited may exist either in the compound or
reagent with which the porous pots plates or partitions are first impregnated or in the
compound or reagent which is afterwards applied.
When we bring about such precipitation or deposition by thermal decomposition wo
impregnate the porous pots plates or partitions with a substance or compound con-
taining the body or element which it is desired to precipitate or deposit and thereafter
we subject the impregnated porous pots plates or partitions to the action of heat so as
to bring about the necessary decomposition for the purpose of depositing in the pores
and interstices of the porous pots plates or partitions.the body required to be precipitated
or deposited.
Having thus described in general terms the nature and object of our invention we
shall now proceed to describe in what manner it is to be or may be carried into effect
and for this purpose we shall describe by way of types or examples one way of
carrying out our invention in the case of each of the methods herein before referred
to that is to say in the case of the chemical method and the thermal method.
In the following descriptions we show how we may perform our invention in the
case of a porous partition-plate and we desire it to be understood that these descriptions
apply equally well when a porous pot or porous cell is treated instead of a porous
plate. We also wish it to be understood that when desired the same plate may be
treated by both of the methods specified.
A convenient way of treating a plate by the chemical method is as follows. We first
prepare a solution of Silicate of Soda containing as little free alkali as possible or in
other words having as large a proportion of Silicic Acid present as is possible. Into
this we plunge the plate and allow it to soak for a period of say 6 to 12 hours such
period varying with the thickness and density of the plate. We then remove the
plate from the solution wipe it and immerse it in a ten per cent. solution of Sulphuric
Acid and leave it to soak therein for a period of say 6 to 12 hours. We then remove
the plate wash it in clean water and dry it at about the temperature of boiling water
for the purpose of abstracting the water of combination from and rendering pulveru-
lent the gelatinous Silicic Acid in the pores and interstices of the plate. If after so
treating by this process the plate has not been raised to the required resistance the
process must be carried out a second time using more dilute solutions.
A convenient way of treating a plate by the thermal method is as follows. We
immerse the plate in a solution of sugar leaving it therein for a sufficient time to allow
of the solution soaking thoroughly into it after which we remove the plate and subject
it to a high temperature in a closed vessel and either packed or not with powdered
charcoal for the purpose of carbonising the sugar and depositing the carbon thereof in
the pores and interstices of the plate. In practice we find it convenient to keep the
sugar solution at a temperature close to that of the boiling point of water during
nearly the whole of the time that the plate is immersed and allow it to cool down
before the plate is removed. We find that employing a thirty per cent. solution of
sugar and soaking the plate therein for a period of say 5 hours gives good results.
If it should be found that the plate has not been brought up to a sufficient resistance
the process must be repeated as often as required preferably using a weaker solution
with cach repetition to avoid exceeding the required limit.
It will be seen that by means of our invention any desired predetermined resistance
of the porous pots plates or partitions may be obtained.
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
1st. The improvement in the manufacture or treatment of porous pots plates or
partitions for electric batteries consisting in impregnating them with a suitable com-
pound or chemical reagent and causing this to act upon or be acted upon by another
suitable compound or chemical reagent, so that a body which shall not itself enter

page_text: into any chemical action with the electrodes or electrolytes (or otherwise undergo
any deleterious change) detrimental to the action of the battery may be separated
and precipitated or deposited in the pores or interstices of the said porous pots plates
or partitions.
2nd. The improvement in the manufacture or treatment of porous pots plates or
partitions for electric batteries consisting in the impregnation of the same with a
substance containing the body or element to be deposited and afterwards subjecting
them to the action of heat so as to bring about the necessary decomposition of the
said substance for the purpose of precipitating or depositing the said body in the
pores and interstices of the said porous pots plates or partitions.