A Process for Maintaining Positive Plates of Secondary Voltaio Batteries in Good Operative Condition
Year: 1893

page_text: Date of Application, 24th Feb., 1893
Complete Specification Left, 23rd Nov., 1893-Accepted, 24th May, 1894
PROVISIONAL SPECIFICATION.
A Process for Maintaining Positive Plates of Secondary Voltaio
Batteries in Good Operative Condition.
I, LUDWIG EPSTEIN, of No. 5 Cambridge Villas, East Twickenham, in the
County of Middlesex, Electrical Engineer, do hereby declare the nature of this
invention to be as follows:-
When the positive plates of secondary voltaic batteries have been for some time
in action, the peroxide of lead upon them becomes more or less soft and pasty and
is apt to be washed off when the battery is subject to agitation.
My invention relates to a process whereby, when the plates are approaching
such a condition that they would be liable to have their coating of oxide washed
off, I can restore the oxide to its original hard adhesive condition, so that the
plates can again serve for a considerable period. For this purpose, I. first dry the
plates which have their coating soft, I then reduce the oxide by a negative current
and reoxidate by a positive current.
Certain plates are of such character that they can be used either as positive or
as negative plates. In dealing with plates of this kind, I dry the plates and then,
by reversing the polarity of the cell, I render those which were positive negative
and conversely, and in this condition the plates may continue in operation until the
coating of the plates, which are now positive, attains the soft condition, whereupon
the process is repeated.
Dated this 24th dox of Februar 1902
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
A Process for Maintaining Positive Plates of Secondary Voltaic
Batteries in Good Operative Condition.
I, LUDWIG EPSTEIN, of No. 5 Cambridge Villas, East Twickenham, in the
County of Middlesex, Electrical Engineer, 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 :-
When the positive plates of secondary voltaic batteries have been for some time
in action, the peroxide of lead upon them becomes more or less soft and pasty and
is apt to be washed off when the battery is subject to agitation.
My invention relates to a process whereby, when the plates are approaching
such a condition that they would be liable to have their coating of oxide washed
off, I can restore the oxide to its original hard adhesive condition, so that the
plates can again serve for a considerable period. For this purpose, I remove from
the cells the plates which have their coating soft, and dry them. I then first
reduce the oxide by a negative current and reoxidate by a positive current and
replace them in the cell.
Certain plates are of such character that they can be used either as positive or
as negative plates. In dealing with plates of this kind, I dry both the positive and
negative plates and then, by reversing the polarity of the cell, I render those which
were positive negative and conversely, and in this condition the plates may continue
Price 8d1

page_text: in operation until the coating of the plates, which are now positive, attains the soft
condition, whereupon the process is repeated.
When plates that have been acting as negative have to be rendered positive, they
should be dried or washed with water before being subjected to the necessary
reversal of current.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The herein described process for hardening the active material on the positive
plates of secondary voltaic batteries by drying the plates, reducing them to negative
condition and again restoring them to positive condition.
2. The modified process for the above purpose which consists in drying both the
positive and the negative plates and then subjecting them together to reversal of
current, rendering those that were positive negative and conversely.
Dated this 14th day of November 1893.
ABEL & IMRAY,
Agents for the Applicant.