Honolulu star-bulletin. [volume] (Honolulu [Oahu, Hawaii]) 1912-2010, 1916-11-25
10y Special Permission from Motor
AQe.)

customary 10 replace IL with a new
plate; or, in the case OF dry cell, TO
replace the entire cell with a new
CELL lf a current of electricity be
sent through the cell from an outside
source in q direction opposite TO the
direction Of the pressure produced by
the cell and the metal In the electro
lyte deposited back on the negative
plate, instead OF replacing the plate
or the entire cell, the cell Is called a
storage battery. When a current Is
passing through storage cell in the
direction OF the pressure, that is, from
the negative TO the positive plate with
in the cell, the cell is said to be dis
charging. and, when a current is pass
ing through the cell in the opposite
direction to its pressure, that Is, from
the positive to the negative plate
within the cell, the cell is said to be
charging.
The fundamental principles OF the
storage battery differ In no way from
the primary cell; that is, any primary
cell could be used as a storage cell
and have its negative plate restored
by sending current through the cell
In the opposite direction to its pres
sure, as Is done In the commercial
types Of storage cells. The ordinary
primary cell cannot have its negative
plate restored economically, and hence
II is commercially more efficient
either TO replace the negative plate
with new one or to replace the en-
tire cell when the negative plate has
nearly wasted away. There are, how
ever, some certain combinations Of
plates and electrolytes which may be
used as aNstorage cell when especially
constructed for the purpose.
You must get this fact clearly fixed
IN your minn--a storage cell does not
store electricity but it stores chem
icai energy
During the process of charging cleo
trieal energy is transformed into
chemical energy and stored within the
cell, while during the process of dis
charging chemical energy is trans
formed back into electrical energy.
Neither OF these transformations is
made without some loss which pre-
vents rs much energy being drawn
from the cell when 1t Is discharging
as was put into it when it was charg-
ing.
Types OF Storage Cells
Storage cells may be divided into
two main groups according to the
kind OF materials used in the cen
struction OF the plates. These groups
are lead storage cells and nonlead
storage cells. and the construction
and operation Of the two types will
be discussed somewhat at length in
the following sections. A great deal
more attention will be given to the
lead storage battery on account of its
characteristics ct present being such
as to, make 1t much better suited to
the requirements Of the starting and
lighting equipment.
In the construction of the lead stor.
age cell the cathode, or positive plate,
is composed OF lead peroxide, PbO2;
the negative plate, or anode, is CON-
posed Of pure spongy lead, Pb, and the
electrolyte is sulphuric acid, H2SO4,
diluted with water, H2O.
Spongy lead and lead peroxide are
rather roor conductors Of electricity.
and their mechanical characteristics
are such that they cannot be made in.
TO plates themselves, and il is neces-
sary that they be supported by frames
OF some material which is stronger
and harder and at the same, time a
better conductor of electricity. The
material used for these frames must
be one which is not acted upon by the
acid. as otherwise there would be
local action between the spongy lead
and the frame or between the lead
peroxide and frame whenever they
happened to be In contact. The ma
terial that is most generally used in
constructing these frames, usually
called grids, Is an alloy of lead
and anthony, (which is mechanically
stronger and sitter than pure lead,
and 1t Is not acted upon to any great
extent by the sulphuric acid.
The lead peroxide and spongy lead
are usually spoken of as the active
materials, in order to distinguish them
from che grids. The combination of
active material and framework is
spoken of as plate. 1t is a positive
plate when 1t is a combination of lead
peroxide and the framework, and mega
tive plate, when il is a combination of
spongy lead and the framework.
General Types CT Lead Cells
There are two general methods of
attaching the active material of a
plate to the framework, and these
methods Of constructing the plates
give rise to two types OF lead cells.
These two types are known as the
Plante and the Faure.
The Plante plate is made by taking
sheet of lead and preparing its sur
face 50 that q large area is exposed
and then oxidizing this surface into
lead peroxide by treating the plate
chemically or by means of an electric
current, thus forming the positive
plates. The negative plates are
formed by taking the peroxide plates
and connecting them as the catholics
with lead sheets as the anodes, in
solution Of diluted sulphurie acid, and
passing a current from one plate to
the other from an outside source. The
hydrogen set free from the acid COM
bines with the oxygen Of the lead