Improvements in Insulating Devices for the Electrodes of Accumulators.
Year: 1898

page_text: Date of Application, 21st Oct., 1898--Accepted, 26th Nov., 1898
COMPLETE SPECIFICATION.
Improvements in Insulating Devices for the Electrodes of
Accumulators.
We, JACOB HEINRICH GRAEBER, of 141, Hammerstrasse, Basle, Switzerland,
Engineer, and HENRI TOBLER, of 35-37, Greifengasse, Basle, Switzerland,
Inventor, 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:-
This invention relates to an insulating device for the electrodes of accumulators.
The insulating devices of this kind which have been heretofore known and
employed, such as the insulators composed of perforated sheets of celluloid, resinous
gum, wool, felt, asbestos, or glass-wool, etc., etc., do not withstand after a time the
combined actions of the concentrated acid and of oxygen in the nascent state,
when they are situated in proximity to the electrodes and especially to the positive
electrode or anode, and in an even less degree when they are in direct contact with the
said electrodes.
Moreover the perforated sheet of celluloid does not prevent in any way the
escape or crumbling away of particles of the active mass." Insulators composed of
granular material give rise to the formation of small projecting parts from which
fine particles of active mass separate or crumble away and produce short circuiting.
Finally, the electrodes heretofore employed increase the internal resistance of the
cells and render the circulation of the electrolyte difficult. When these insulators
are in direct contact with the electrodes the operating surface of the latter is
considerably reduced. All these drawbacks are obviated by the present invention.
The accompanying drawings illustrate by way of example a form of construction
of an insulating device according to this invention. In these drawings Figure 1
is a vertical section of an accumulator element having three insulated electrodes.
Figure 2 is a horizontal section of an electrode with an arrangement or device for
lateral insulation, and Figure 3 is an external view of an electrode composed of
separate plates.
As shewn in these drawings, inside the vessel or receptacle G, there are arranged
the supports B, each formed with a slot N for the reception of an electrode com-
posed of separate plates. These plates are connected to the collecting strip a
by means of a pin M fixed for instance by rivetting or plumbing. Each of the
plates of electrode is composed of a lead frame a¹ which contains the active mass all.
The two sides of the supports B are provided with inclined notches in which are
arranged the insulating tiles or slabs C which may for example be of glass, and
which by reason of being arranged side by side next to the various supports B,
form insulating walls or partitions in the form of roofs. Further, between the
insulating partitions and the electrodes there is also provided an interval of
space R.
The circulation of the electrolyte is therefore free, which is not the case in
ordinary insulating arrangements. The internal resistance of the elements or cells
will not be increased. There is no contact with the surface of the active mass of

page_text: the electrode. The latter can therefore produce its entire effect. The distance
between the several electrodes is exactly regulated. All possibility of short
circuiting is excluded because any particles which may become separated from the
mass, cannot get to the opposite electrode but are compelled to fall down the
space R to the bottom of the vessel or receptacle G.
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:-
(1) An insulating device for the electrodes of accumulators, constituted by two
uprights, the inner faces of which are connected together by means of two series
of glass plates arranged obliquely on each side of the electrode and adapted to slide
in grooves formed in the said inner faces, as set forth.
(2) An insulating device for the electrodes of accumulators substantially as above
described and shewn in the accompanying drawings.
Dated this 21st day of October 1898.
ROBERT E. PHILLIPS, Assoc. M. Inst. C.E., M.I. Mech. E.,
Chartered Patent Agent,
70, Chancery Lane, London, W.C. Associate Agent.