Improvements in Electrodes or Plates for Secondary Batteries.
Year: 1899

page_text: COMPLETE SPECIFICATION.
Improvements in Electrodes or Plates for Secondary Batteries.
I, LOUIS GEORG LEFFER, of the Accumulatoren Werke Colonia, Leffer & Co.,
Commandit Gesellschaft, Manufacturers, of 41, Hohenzollernring, Cologne on the
Rhine, Germany, 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: —
The present invention has for its object, to construct electrodes or plates for
electric accumulators, which combine high capacity, with long life, even in case
of irregular working, and a minimum of weight.
In the accompanying drawings:
Fig. 1 is a partial face view of an accumulator electrode composed of several
plates,
Fig. 2 is a cross section of the same.
Each positive plate chiefly consists of a solid lead core a having on both sides
horizontal ribs which stop short of the edges of the plate, and also projections c
formed on the edges of the plate.
The negative plates differ from the positive plates only by having in the
core a perforations arranged between the ribs at regular intervals, for allowing
the electrolyte to pass from one side of the plate to the other. In some cases
such perforations may be formed also in the positive electrodes.
An electrode or battery element is formed by providing one or more of the
ribbed plates with a frame d of hard lead, which grasps the projections of the
same for about half their width, so that a gap or recess c is formed between
contiguous projections and the leaden frame d, through which a junction is
established between the active mass on both sides of the plate, which junction
serves to secure the active mass to the plate and to conduct the electricity to
the frame d.
C
The projections at the edges of the plate a may be rectangular, triangular,
trapezoidal, or of any other suitable shape.
As shown by Fig. 2, the ribs b, which do not extend to the edges of the plate,
are thicker at their free end or head, than at their base, and are directed upward,
so as to form dove-tailed grooves adapted to hold and support the active mass
introduced between the ribs. This arrangement facilitates the expansion of the
mass projecting over the ribs and form an intimate contact and good electric
connection between the mass and the leaden frame d.
The electrode represented by Fig. 1 is composed of four or more plates a, held
at their projections or teeth c by a leaden frame d.
As mentioned above, the characteristic features of the invention are, that the
ribs & do not extend to the edges of the plate a, that they are wedge-shaped and
directed upward, so as to facilitate the expansion and contraction of the active
mass or filling, also the arrangement of the projections or teeth c, on the edges of
the core plate, which are grasped by the leaden frame d up to about half their
width, so as to form recesses e.
The active mass in front of the core is joined together with that at the back

page_text: through the recesses e formed between the teeth c and forms good electric contact
with a large surface of the lead frame all around the edges of the plates a.
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
1 claim is:-
1. An electrode for accumulators or secondary batteries, having a core plate
or plates a provided with ribs which stop short of the edges, and with pro-
jections or teeth c formed on the edges, in combination with a frame d of con-
ducting material adapted to grasp the projections c of a plate or plates a, so as to
form gaps e, through which the active mass applied to the front of the plate
forms a junction with that on the back, in order to hold the said mass and
establish intimate electric contact with the conducting frame d.
2. An electrode for accumulators or secondary batteries having plates held by a
conducting frame, each plate being provided with upwardly directed ribs which
are thicker at the head than at the base and do not extend to the edges of the
plate.
3. In a negative or positive electrode of the type specified, a ribbed metal core
or plate having between the ribs perforations arranged at regular intervals.
Dated this 30th day of May 1899.
FAIRFAX & WETTER,
Agents, 37 and 39, Essex Street, Strand, London.
FAIRFAX & WETTER,
Agents, 37 and 39, Essex Street, Strand, London.