An Improved Method of Preparing Positive Plates for Secondary Batteries.
Year: 1897

page_text: An Improved Method of Preparing Positive Plates for Secondary
Batteries.
HENRY WILLIAM HANDCOCK & ALFRED HERBERT DYKES both of 5 Victoria Street
Westminster, S.W. Engineers do hereby declare the nature of this invention to be
as follows:-
.
Our invention relates to the production of positive plates for accumulators
by peroxydising metallic lead by passing the electric current through lead
plates when immersed in an acid solution to which has been added a suitable
proportion of a nitroso compound as set forth below. In our experiments we have
used the nitrites of the alkali metals but have not obtained fully satisfactory results,
owing to the fact that on their addition to a solution of sulphuric acid the nitrous
gases are evolved and only partially combine with the negative radicle of the acid.
On the other hand we find that by using the nitrites of ammonium or organic
ammonium bases (such as Lenthine) or other organic bases containing NH, NH₂
&c, a very different action takes place. On adding any of these to the dilute solution
of H₂SO. little or no gas is given off and the solution becomes more complex in its
constitution. The resulting liquid has a most remarkable property when used as an
electrolyte with lead plates for the electrodes, the positive pole being peroxydised
extremely rapidly.
The peroxide formed is of a hard nature and the resulting plate is well suited in
every way for use as the positive plate in storage batteries in the place of a plate
formed by the ordinary Planté process, the latter being similar but much inferior in
adaptability for the purpose in view. Our process gives a much more even surface
and therefore a thinner deposit is required for the same capacity. The surface is of
such a crystalline nature that the gases do not hang to it and there is less disparity
between the charging and discharging voltages than is usually the case.
We have so far found that the best density for the sulphuric acid is about 1.05 and
in the ordinary way we use the nitrite of ammonium which must be mixed quickly
with the acid. We vary the time of forming from two to five or more days according
to the nature of the peroxide required.
HENRY WILLIAM HANDCOCK.
ALFRED HERBERT DYKES.

page_text: An Improved Method of Preparing Positive Plates for Secondary
Batteries.
HENRY WILLIAM HANDCOCK and ALFRED HERBERT DYKES both of 5 Victoria Street
Westminster, S.W. Engineers 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 :-
Our invention relates to a method of producing positive plates for accumulators by
peroxydising metallic lead by passing the electric current through lead plates when
immersed in an acid solution to which has been added a suitable proportion of a
nitroso compound. as set forth below.-In our experiments we have used the nitrites
of the alkali metals, but have not obtained fully satisfactory results, owing to the fact
that on their addition to a solution of Sulphuric acid the nitrous gases are evolved and
only partially combine with the regative radicle of the acid. On the other hand we
find that by using the nitrites of ammonium or organic ammonium bases
(such as Lenthine) or other organic bases containing NH, NH,, &c, a very different
action takes place. On adding any of these to the dilute solution of H2SO4 comparatively
little or no gas is given off and and the solution becomes more complex in its constitution.
The resulting liquid has a most remarkable property when used as an electrolyte
with lead plates for the electrodes, the positive pole being peroxydised extremely
rapidly.
The peroxide formed is of a hard nature and the resulting plate is well suited for
use as the positive plate in storage batteries. Our process gives a very even surface
and therefore a thinner deposit is required than in the case of a plate formed by the
ordinary Planté process for the same capacity. The surface is of such a crystalline
nature that the gases do not hang to it and there is less disparity between the
charging and discharging voltages than is usually the case.
We find that the best density for the acid is 1.05 and use by preference the nitrite
of ammonium of density about 1.1. The two must be mixed quickly. We can also
take instead of pure nitrite, constituents in equivalent proportions which produce
the nitrite, such as sodium nitrite and ammonium sulphate. From two to five days
is a convenient time for forming and if the time is reduced below two days for a
plate of normal capacity the ampère hour efficiency of the forming is somewhat
reduced.
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
The method of forming positive plates for secondary batteries as herein set forth by
the agency of the nitrites of ammonium or organic ammonium bases or other organic
bases containing NH, NH,
י-נ.י.ם
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