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ON M. C. FAURE'S SECONDARY BATTERY.


The researches of M. Gaston Plante on the polarization of voltameters
led to his invention of the secondary cell, composed of two strips of
lead immersed in acidulated water. These cells accumulate, and, so to
speak, store up the electricity passed into them from some outside
generator. When the two electrodes are connected with any source of
electricity the surfaces of the two strips of lead undergo certain
modifications. Thus, the positive pole retains oxygen and becomes
covered with a thin coating of peroxide of lead, while the negative pole
becomes reduced to a clean metallic state.

Now, if the secondary cell is separated from the primary one, we have a
veritable voltaic battery, for the symmetry of the poles is upset, and
one is ready to give up oxygen and the other eager to receive it. When
the poles are connected, an intense electric current is obtained, but
it is of short duration. Such a cell, having half a square meter of
surface, can store up enough electricity to keep a platinum wire 1
millim. in diameter and 8 centims. long, red-hot for ten minutes. M.
Plante has succeeded in increasing the duration of the current by
alternately charging and discharging the cell, so as alternately to
form layers of reduced metal and peroxide of lead on the surface of the
strip. It was seen that this cell would afford an excellent means for
the conveyance of electricity from place to place, the great drawback,