Year: 1889

page_text: I, WILLIAM JOSEPH STARKEY BARBER-STARKEY of Aldenham Park Bridgnorth in
the County of Salop, Barrister, do hereby declare the nature of this invention, and
in what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
=
This Invention relates to electric batteries and more particularly to secondary and
storage batteries and cells which are designed and intended to be moved from place to
place.
According to these Improvements the positive and the negative plates or electrodes
are embedded in, or surrounded and separated by a porous substance which is saturated
with the solution of sulphuric acid or other electrolytic solution. I prefer to employ
calcined calcium sulphate or plaster of paris as a basis of the porous material especially
in the case of batteries in which a solution of sulphuric acid is employed as the electro-
lyte. The natural porosity of the plaster of paris (when gauged and set) is increased
for the purpose of this Invention by the addition thereto of certain materials, such as
crystals of salts soluble in water or in the electrolyte and which are dissolved out of
the plaster after it has set, salts which are decoinposed by the electrolyte or by a
suitable acid and having as one of the products of the decomposition a gas such as
carbon dioxide; or by the addition of an insoluble fibrous or porous material such as
saw dust, pith, cork, asbestos, wool, hair, felt, pumice stone, and similar substances.
In carrying out my Invention, I prefer to place the plates or electrodes in the cell
in the positions assigned to them, and then to pour into the vacant spaces between and
around the plates, the mixture of the dry plaster of paris and the added material or
materials The solution of sulphuric acid or other electrolyte is then poured into the
pulverulent or mixed material, whereupon the plaster of paris will become hydrated
and will set with the included material, into a solid porous mass within which the
electrodes will be firmly included so as to be incapable of being relatively disturbed or
of having their active material detached during subsequent use. The porosity of the
mass allows it to absorb and permits the free circulation therein of a considerable
quantity of the electrolyte ; while for the same reason the internal resistance of the
battery is not so increased to such an extent as when less porous materials, such as
plaster of paris alone, are used. Instead of pouring or packing the mixed plaster and
other material in the dry state between and around the electrodes, and then pouring

page_text: the solution thereon as described, the mixed materials may be gauged, and be packed
between and around the plates in the cell whilst the gauged mass is still in a plastic
condition. Or, the materials may be gauged and cist or otherwise formed into plates
and blocks which may, after they have hardened, be placed between and around the
plates in the cell.
The porosity of the mass is increased as herein before set forth, by the addition of
crystals of a soluble salt, by the addition of a decomposable salt yielding gas on
decomposition, or by the addition of an insoluble porous substance.
When the crystals of soluble salt are used, and when the electrolyte is a solution of
sulphuric acid, I prefer to employ crystalline or pulverulent sulphates of sodium,
potassium, ammonium, oi magnesium If these or similar salts are mixed with the
dry plaster of paris and the mixture is then quickly ganged, the salts have not time to
dissolve in the water added to the mass for the purpose of hydration, and they therefore
become included in the solidified mass practically unaltered. The salts may be
dissolved out by the electrolyte, or by water, before the mass is placed in the cells;
in either case the spaces occupied by the salts will become vacant, and the mass will
be additionally porous to that extent Other salts than those herein before mentioned
may be employed, especially when the electrolyte is some other than a solution of
sulphuric acid
If the material added to the plaster of paris is a salt which is capable of yielding
gas upon decomposition I prefer to employ the carbonates of the alkalies and of the
alkaline earths The mass in this case is gauged with a solution of sulphuric acid, and
the consequent liberation of the carbon dioxide therein renders it spongy or porous.
When the carbonates or similar salts are used, it will always be preferable to pour or
pack the diy mature between and around the plates in the cell and then pour the
solution of sulphuric acid thereon as hereinbefore described
When the additional porosity is to be gained by the addition of a suitable insoluble
material with the plaster, 1 prefer to shied or divide the material and to mix it with
the dry plaster The mixture may then be gauged separately to form plates or to be
poured or packed between and around the plates, or the day material may be placed m
the cells and be gauged by the addition of the electrolyte as herembefore described.
When this insoluble addition is used I prefer, in the case of secondary batteries of
batteries in which a solution of sulphuric acid is used, to add either to the plaster, to
the water with which it is gauged, or to the solution of sulphuric acid, a small quantity
of carbonate of one of the alkalies or of magnesium
I prefer to use calcined plaster of paris as the cementing component of the porous
mass, because it is the cheapest and most generally convenient material for the purpose
with which I am at present acquainted, but other sumilar and suitable comenting or
agglutinating substances may in some cases be employed, such for example as
hydraulic cement in soda or saline solutions, the selection of such a material will be
determined by the nature of the electrolyte and by other conditions of use as is well
understood.
When the battery has the porous mass set or finally hardened or placed in the cells,
and this mass is saturated with the electrolyte, there may be poured upon its surface
melted paraffin wax, pitch or other similar materiai, for the purpose of still further
1 educing the 1sk of spilling the electrolyte from the cell in use; for preventing
evaporation and to insulate the tops of the plates
;
When a cell of a battery has been constructed or arranged with a porous material
between the plates as hereinheiore described, it is very safely portable and convenient
for use.
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 18:
(1) Embedding surrounding and separating the plates or electrodes of electric
batteries in and by a porous material substantially as and for the purpose herein before
decoribed

page_text: (2) In electric batteries, a porous mass embedding separating and surrounding
the electrodes and containing the electrolyte, said porous mass being formed from a
mixture of soluble salts and a cementing agent pervious to water, and the salts being
dissolved out after the mass has set or hardened; substantially as and for the purpose
herein before described
(3) In electric batteries; a porous mass embedding separating and surrounding the
electrodes and containing the electrolyte, said porous mass being formed from a mixture
of salts yiel ling gas on decomposition and a cementing agent pervious to water, and
the salts being decomposed during or immediately before the hardening of the porous
mass, substantially as and for the purpose hereinbefore described
(4) In electric batteries, a porous mass separating and surrounding the electrodes
and containing the electrolyte said mass being formed of fibrous, pervious and similar
insoluble substances mixed with a suitable cementing agent pervious to water, all sub-
stantially as and for the purpose hereinbefore described.
Dated this 4th day of May A D 1889
WILLIAM E. HEYS,
Agent for the Applicant.