The L'Anse sentinel., 1923-01-26
HOW THE STORAGE
BATTERY OPERATES
Operator Must Guard Against an
Excessive Rate Of Charge
or Discharge.

of sulphurlc acid and continuously go
ing through the charging and dis
charging process. However, THIS Is
long and tedious process to get OXIDE
of lead on the positive plates by means
of numerous charging and discharglng
cycles. The oxide, which is the active
material, is manufactured chemically
and applied to the plates.
The body of manufactured plates is
cast from lead in such manner as
to leave the surface honeycombed. In
this boneycombed surface OF the
plates is forced paste, formed by
mixing litharge-lead-oxide with sui
phuric acid After the plates are as
sembled with separators between they
are placed in containers in an electro
lyte consisting Of 20 per cent So
luton of sulphuric acid. The lead
body of storage battery plate simply
acts as holder or container for the
active material. The active materials
In lead storage battery are the lead
peroxide on the positive plate, the
sponge lead of the negative plate ana
the sulphuric acid electrolyte.
When storage battery is discharg-
ing. that Is, while current is being
drawn from it, chemical action taxes
place in the battery. The lead per-
oxide Of the positive plate and the
sulphuric acid Of the electrolyte react
to form lead sulphate and water. Acid
Is more dense than water, so that
when fully charged the electrolyte has
density of 1875 TO 1900, which
means that the electrolyte Is 1.275 to
1.3 times as heavy as an equal volume
Of water. AS the battery is discharged
and water is formed by the chemical
action, the electrolyte becomes less
dense. Finally, when the density
drops to 100 to 1.150, the battery
reaches n point when charging Is nee
essary. Thus the density of the cleo
trolyte is a measure of how much en-
ergy, or how fully charged the bat
terry Is.
The voltage of a battery Is also
an indication Of the degree OF charge.
A fully charged battery should have
>an open circuit voltage of % volts
per cell.
The voltage per cell should not be
allowed to drop below 1.S before re
charging.
When a storage battery is put on
charge, a direct current Is forced
through the battery. The chemical
reaction that takes place during the
charging process is just the reverse
of that which takes place during the
process of discharging. That is to say,
the lead sulphate and water formed
during the discharge are converted
back into lead peroxide and sulphuic
acid. The formation of sulpGurtc
acid during the charging process
causes the density of the electroiyte
to increase. The density of the cleo
trolyte of fully charged battery Is
between 1875 and 1900, while the
open circuit voltage per cell Is about
%.
OF course, storage battery is not
100 per cent efficient, which means
that the total ampere hours delivered
to the battery during the charging pc
riod will always exceed the total am
pere hours drawn from the battery
during the discharge period. The
voltage per cell and the specific grav-
ity Of the electrolyte are the criterion
of the degrees of charge in the battery.
However, due TO the fact that some of
the lead sulphate Is not readily con-
verted into lead peroxide and sui
phuric acid, 1t Is necessary at times
to give the battery an over
charge That is, the charging cur
rent should be allowed to flow after
the battery has reached the charged
condition, until after several hours of
constant charging, there is no In
crease In the voltage per cell or the
density Of the electrolyte.
The value of the charging current
is determined by the manufacturers
and should not be exceeded. An ex-
cessively high charging current will
cause an increase In the rate Of de
terioration of the plates. Every time
q battery Is charged or discharged a
certain amount Of active material on
the plates crumbles and drops to the
bottom Of the cell.
Assuming the same operating con-
ditions, the life of storage battery is
certain number of charges and dis
charges. An excessive rate of charge
or discharge will cause the battery to
heat. buckle the plates, and result In
an abnormal amount of crumbling of
the active material. In the extreme
case of a short circuit, the plates Of
the battery might be buckled to such
an extent that an internal short cir
cult is formed in the battery. To
guard against short circuits 1t Is well
when using lead plate storage bat
terry to install fuse In both battery
leads right near the terminals of the
battery. Don't under any condition
spark the battery by placing pair
of pliers or screw driver across the
terminals. This viii eventually ruin
the battery.
The water win evaporate out Of the
electrolyte of a battery and should be
ronlocad AIwava add euou0h dia-