Year: 1899

page_text: I, DONATO TOMMASI, of 6. Rue des Immeubles Industriels, Paris, France,
Engineer, do hereby declare the nature of this invention to be as follows:-
The plates of electric accumulators and particularly the positive plates, are
subject to a series of expansions and contractions which occur in charging and
discharging; these successive movements have for effect to cause disintegration
of the active material adhering to said plates, which after a certain period of. use
renders them unserviceable. With a view to remedy this defect I have devised a
special construction of accumulator electrode in which these movements of con-
traction and expansion or augmentation of volume are rendered insensible.
My improved electrode is formed essentially of a spirally wound metallic
strip between the convolutions of which the active material is retained, this strip
being composed of an elastic rigid metal, antimony lead, or other suitable alloy
of lead, or of a strip of steel copper, bronze, etc., coated with lead. In order to
render the coil unattackable by the electrolyte, it is coated with a composition con-
sisting of a mixture of collodion and a suitable quantity of platinum black,
peroxide of cobalt, binoxide of manganese, or other substance conductive of elec-
tricity but unattackable by the liquid used as the electrolyte. I may also coat the
completed electrode with the same composition, for the purpose of increasing the
cohesion of its constitutive elements.
The accumulator electrode of this invention is further characterized by the
special composition of the active material which consists of oxide of lead mixed
with a certain proportion (about 5%) of oxide of cobalt or binoxide of manganese.
The addition of oxide of cobalt or of binoxide of manganese has the effect of ren-
dering the charging more rapid, more intense, and more regular.
Reference is to be had to the accompanying drawings forming part of this
specification wherein Figure 1 represents an elevation, partly in section, of an
accumulator. Figure 2 is a cross section of the same, on line A B Figure 1.
Figure 3 is a perspective view of an accumulator. Figure 4 is a vertical section
of an electrode and Figure 5 a perspective view of the same. Figures 6 and 7
shew a face view and transverse vertical section of a cathode adapted for use in
conjunction with the improved electrode employed as anode. Figures 8 and 9

page_text: shew a face view and transverse vertical section of a modification of this cathode.
Figure 10 shews a transverse vertical section of another modification of the
cathode. The same letters of reference denote like parts in all the figures.
In this improved accumulator each electrode, and particularly each positive
plate, is constituted by a spirally wound metallic strip a between the coils of
which the active material is retained. The strip would be made of an
elastic rigid metal, for instance of antimony lead or other sufficiently elastic and
rigid alloy of lead, or it might be constituted of a strip of steel, copper, bronze, etc.,
coated with lead, or it may be made by passing lead-coated wire used for tele-
graphic purposes between rolls. This metallic strip may be of any suitable section
for example it may be flat, of I form, or be grooved or corrugated or ribbed
for the purpose of better retaining the active material. The latter may also be
retained laterally by means of cross arms. Each strip a is fixed at one end to a
central boss of insulating material and is contained within a rim also of
insulating material which has a slot in it for the passage of the outer extremity of
the strip a
The electrodes thus constituted are all mounted vertically upon the same hori-
zontal shaft e and are immersed in the liquid electrolyte contained in a trough f.
In order to preserve a certain interval between the electrodes, the rims are
formed with lateral distance pieces or projections g which abut together so as to
permit of the electrolyte circulating freely between the electrodes
and also of clamping them together SO as to prevent any relative
change of position. The set of electrodes may be mounted within the
trough fin any suitable manner, as in Figure 1, which will prevent shifting
in the event of the accumulator being subjected to shock or concussion so as to
render the accumulator especially suitable for use on motor-vehicles. All the
ends of the strips of the positive plates are connected to the same positive con-
ducting rod and the ends of the strips of the negative plates are connected to
the same negative conducting rod i.
In
The hereinbefore described construction of electrode may be employed both
for positive and negative electrodes, or for positive electrodes only in which case
the negative electrode would be preferably constituted as shewn in Figures 6 and 7.
In this case the frame of the negative electrode is made of a flanged disc of
carbon presenting on both faces studs or projections and on its internal circum-
ference corrugations for the purpose of retaining the active material.
Figures 8 and 9 the negative electrode is shewn as formed of a metal disc k
mounted on an insulating core and encircled by a rim also of insulating material
or of conductive material unattackable by the electrolyte. The negative electrode
may also be constructed, as shewn in Figure 10, of a flanged disc of insulating
material each face of which is covered by a metallic disc m upon which the
active material is applied and retained by any suitable non-conducting means
such as cross arms for example.
The active material for the positive electrodes is composed of oxide of lead mixed
with a suitable proportion (about 5%) of oxide of cobalt or binoxide of man-
ganese. This composition may be made either by mechanically mixing in the
proper proportions oxide of lead and oxide of cobalt or binoxide of manganese, or
by electrolyzing a salt of cobalt or of manganese with anodes formed of oxide of
lead in such a manner as to deposit the oxide of cobalt or binoxide of
manganese in the mass of oxide of lead.
In my system of accumulator the electrolyte contains preferably a certain propor-
tion of salts of cobalt or of manganese capable of furnishing under the action of the
current, peroxide of cobalt or of manganese with the object of always maintaining
in the active material the same quantity of oxide of cobalt or of binoxide of
manganese.
The active material of the negative electrodes is constituted preferably, by
mixing oxide of lead or spongy lead with a suitable quantity of crushed carbon
or cranhite

page_text: It is to be understood that the accumulator plates of this invention may ne
varied in form and dimensions and that I may modify the accessory arrange-
ments and mode of mounting to suit different applications.
T1800
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.
I. DONATO TOMMASI, of 6. Rue des Immeubles Industriels, Paris, France,
Engineer, do hereby declare the nature of this invention and in what manner the
ame is to be performed to be particularly described and ascertained in and by the
ollowing statement ;-
and more especially the positive plates, are
The plates of electric accumulators,
ubject to a series of expansions and contractions which occur in charging and
lischarging, and these successive movements have for effect to cause a disintegra-
ion of the active material adhering to the plates which renders them unservice-
With a view to remedy this defect I have
able after a certain period of use.
levised a special construction of accumulator electrode in which these movements
of contraction of expansion or augmentation of volume are rendered insensible.
My improved electrode is formed essentially of a spirally wound metallic strip
between the convolutions of which the active material is retained, this strip being
constituted by an elastic rigid metal, antimony-lead, or other suitable alloy of
lead, or by a strip of steel copper, bronze etc., coated with lead. In order to
render the coil unattackable by the electrolyte it is coated with a composition
consisting of mixture of collodion and a suitable quantity of platinum black,
peroxide of cobalt, binoxide of manganese, or other substance conductive of elec-
tricity but unattackable by the liquid used as the electrolyte. I may also coat
the completed electrode with the same composition, for the purpose of increasing
the cohesion of its constitutive elements.
The accumulator electrode of this invention is further characterized by the
special composition of the active material which consists of oxide of lead mixed
with a certain proportion (about 5%) of oxide of cobalt or binoxide of manganese..
The addition of oxide of cobalt or of binoxide of manganese has the effect of
rendering the charging more rapid, more intense and more regular.
Reference is to be had to the drawings accompanying my Provisional Specifi-
cation wherein Figure 1 represents an elevation, partly in section, of an accumu-
lator. Figure 2 is a cross section of the same, on line A B Figure 1. Figure 3 is
is a vertical section of an elec-
a perspective view of an accumulator. Figure
trode and Figure 5 a perspective view of the same. Figures 6 and 7 shew a face
view and transverse vertical section of a cathode adapted for use in conjunction
with the improved electrode employed as anode. Figures 8 and 9 shew a face
view and transverse vertical section of a modification of this cathode. Figure 10
shews a transverse vertical section of another modification of the cathode. The
same letters of reference denote like parts in all the figures.
.
5 In this improved accumulator each electrode, and particularly each positive
plate, is constituted by a spirally wound metallic strip a between the coils of which
the active material is retained. The strip would be made of an elastic rigid
metal, for instance of antimony-lead or other sufficiently elastic and rigid alloy
of lead, or it might be constituted of a strip of steel, copper, bronze, efe, coated

page_text: with lead or it may be made by passing lead-coated wire used for telegraphic pur-
poses between rolls. This metallic strip may be of any suitable section, for
example it may be flat, of I form, or be grooved or corrugated or ribbed for the
purpose of better retaining the active material. The latter may also be retained
laterally by any suitable means such as cross arms for example. Each strip a
is fixed at one end to a central boss c of insulating material and is contained
within a rim also of insulating material, which rim has a slot in it for the
passage of the outer extremity of the strip a.
The electrodes thus constituted are all mounted vertically upon the same hori-
zontal shaft e and are immersed in the liquid electrolyte contained in a trough f.
In order to preserve a certain interval between the electrodes, the rims & are
formed with lateral distance pieces or projections which abut together so as
to permit of the electrolyte circulating freely between the electrodes and also of
clamping them together so as to prevent any relative change of position. The
set of electrodes may be mounted within the trough f in any suitable manner (as
in Figure 1) which will prevent shifting in the event of the accumulator being
subjected to shock or concussion. The accumulator is thus especially suitable for
use on motor-vehicles.
The ends of the strips of the positive plates are all connected to the same
positive conducting rod h and the ends of the strips of the negative plates are all
connected to the same negative conducting rod i.
The herein before described construction of electrode may be employed both
for positive and negative electrodes, or for positive electrodes only, in which case
the negative electrode would be preferably constituted as shewn in Figures 6
and 7. In this case the frame of the negative electrode is made of a flanged disc
of carbon presenting on both faces studs or projections and on its internal
circumference corrugations, for the purpose of retaining the active material.
In Figures 8 and 9 the negative electrode is shewn as formed of a metal dise k
mounted on an insulating core and encircled by a rim also of insulating material
or of conductive material unattackable by the electrolyte.
The negative electrode may also be constructed, as shewn in Figure 10, of a
flanged disc of insulating material, each face of which is covered by a metallic
disc m upon which the active material is applied and retained by any suitable
non-conducting means such as by cross arms for example.
The active material for the positive electrodes is composed of oxide of lead mixed
with a suitable proportion (about 5%) of oxide of cobalt or binoxide of manganese.
This composition may be made either by mechanically mixing in the proper pro-
portions oxide of lead and oxide of cobalt or binoxide of manganese, or by electro-
lyzing a salt of cobalt or of manganese with anodes formed of oxide of lead in
such manner as to deposit the oxide of cobalt or binoxide of manganese in the
mass of oxide of lead.
.
In my system of accumulator the electrolyte contains preferably a certain
proportion of salts of cobalt or of manganese capable of furnishing under the
action of the current, peroxide of cobalt or of manganese with the object of
always maintaining in the active material the same quantity of oxide of cobalt
or of binoxide of manganese.
The active material of the negative electrodes is constituted preferably by
mixing oxide of lead or spongy lead with a suitable quantity of crushed carbon
or graphite.
It is to be understood that the accumulator plates of this invention may
be varied in form and dimensions and that I reserve the right to modify the
accessory arrangements and mode of mounting to suit different applications.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is-
1. An electrode for electric accumulators adapted to accomodate the expansions

page_text: and contractions of the active material in charging and discharging and con-
structed of a spirally wound metallic strip between the coils of which the active
material is retained, the strip being constituted by an elastic rigid metal such
as antimony-lead or other suitable alloy of lead, or by a strip of steel, copper,
bronze, etc., coated with lead, and the active material being composed of oxide of
lead mixed with a certain proportion (say about 5%) of oxide of cobalt or binoxide
of manganese.
2. An electrode constructed as specified in the preceding claim and in which
the spiral metallic strip is rendered unattackable by the electrolyte by a coat-
ing of collodion mixed with a suitable quantity of platinum black, peroxide of
cobalt, or binoxide of manganese, or other substance conductive of electricity but
unattackable by the electrolyte.
3. The application to the completed electrode of the coating specified in the
preceding claim for the purpose of increasing the cohesion of its constitutive
elements.
4. An accumulator constituted exclusively by electrodes constructed as herein
described, said electrodes being mounted vertically upon a horizontal shaft carried
by the trough containing the electrolyte in which the electrodes are immersed,
the latter being so mounted that any shifting of position within the trough is
prevented as specified.
5. An accumulator of which the positive electrodes are constructed as herein-
before specified and claimed and in which the negative electrodes are each formed
of a carbon disc recessed on each face to receive the active material composed of
a mixture of oxide of lead and carbon or graphite, or of a mixture of spongy
lead and carbon or graphite as described with reference to Figures 6 and 7.
6. An accumulator of which the positive electrodes are constituted as specified
in the first and second claiming clauses, and of which the negative electrodes
are each formed of a vertical disc or core of conducting material upon both
faces of which the active material is applied, said core of conducting material
preferably consisting of carbon or of insulating material faced on both sides with
sheet metal as described with reference to Figures 8, 9 and 10.
Taal 1: 0041, fl 1000
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.